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1.
Nature ; 605(7910): 509-515, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35545674

RESUMEN

Recent understanding of how the systemic environment shapes the brain throughout life has led to numerous intervention strategies to slow brain ageing1-3. Cerebrospinal fluid (CSF) makes up the immediate environment of brain cells, providing them with nourishing compounds4,5. We discovered that infusing young CSF directly into aged brains improves memory function. Unbiased transcriptome analysis of the hippocampus identified oligodendrocytes to be most responsive to this rejuvenated CSF environment. We further showed that young CSF boosts oligodendrocyte progenitor cell (OPC) proliferation and differentiation in the aged hippocampus and in primary OPC cultures. Using SLAMseq to metabolically label nascent mRNA, we identified serum response factor (SRF), a transcription factor that drives actin cytoskeleton rearrangement, as a mediator of OPC proliferation following exposure to young CSF. With age, SRF expression decreases in hippocampal OPCs, and the pathway is induced by acute injection with young CSF. We screened for potential SRF activators in CSF and found that fibroblast growth factor 17 (Fgf17) infusion is sufficient to induce OPC proliferation and long-term memory consolidation in aged mice while Fgf17 blockade impairs cognition in young mice. These findings demonstrate the rejuvenating power of young CSF and identify Fgf17 as a key target to restore oligodendrocyte function in the ageing brain.


Asunto(s)
Envejecimiento , Encéfalo , Líquido Cefalorraquídeo , Células Precursoras de Oligodendrocitos , Oligodendroglía , Animales , Diferenciación Celular/genética , Líquido Cefalorraquídeo/fisiología , Factores de Crecimiento de Fibroblastos/metabolismo , Regulación de la Expresión Génica , Ratones , Células Precursoras de Oligodendrocitos/metabolismo , Oligodendroglía/metabolismo
2.
Proc Natl Acad Sci U S A ; 121(12): e2307250121, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38483990

RESUMEN

Myelination of neuronal axons is essential for nervous system development. Myelination requires dramatic cytoskeletal dynamics in oligodendrocytes, but how actin is regulated during myelination is poorly understood. We recently identified serum response factor (SRF)-a transcription factor known to regulate expression of actin and actin regulators in other cell types-as a critical driver of myelination in the aged brain. Yet, a major gap remains in understanding the mechanistic role of SRF in oligodendrocyte lineage cells. Here, we show that SRF is required cell autonomously in oligodendrocytes for myelination during development. Combining ChIP-seq with RNA-seq identifies SRF-target genes in oligodendrocyte precursor cells and oligodendrocytes that include actin and other key cytoskeletal genes. Accordingly, SRF knockout oligodendrocytes exhibit dramatically reduced actin filament levels early in differentiation, consistent with its role in actin-dependent myelin sheath initiation. Surprisingly, oligodendrocyte-restricted loss of SRF results in upregulation of gene signatures associated with aging and neurodegenerative diseases. Together, our findings identify SRF as a transcriptional regulator that controls the expression of cytoskeletal genes required in oligodendrocytes for myelination. This study identifies an essential pathway regulating oligodendrocyte biology with high relevance to brain development, aging, and disease.


Asunto(s)
Actinas , Factor de Respuesta Sérica , Actinas/genética , Actinas/metabolismo , Factor de Respuesta Sérica/genética , Factor de Respuesta Sérica/metabolismo , Oligodendroglía/metabolismo , Vaina de Mielina/genética , Vaina de Mielina/metabolismo , Citoesqueleto/genética , Diferenciación Celular/genética
3.
J Biol Chem ; 299(6): 104773, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37142225

RESUMEN

The bacterial RadD enzyme is important for multiple genome maintenance pathways, including RecA DNA strand exchange and RecA-independent suppression of DNA crossover template switching. However, much remains unknown about the precise roles of RadD. One potential clue into RadD mechanisms is its direct interaction with the single-stranded DNA binding protein (SSB), which coats single-stranded DNA exposed during genome maintenance reactions in cells. Interaction with SSB stimulates the ATPase activity of RadD. To probe the mechanism and importance of RadD-SSB complex formation, we identified a pocket on RadD that is essential for binding SSB. In a mechanism shared with many other SSB-interacting proteins, RadD uses a hydrophobic pocket framed by basic residues to bind the C-terminal end of SSB. We found that RadD variants that substitute acidic residues for basic residues in the SSB binding site impair RadD:SSB complex formation and eliminate SSB stimulation of RadD ATPase activity in vitro. Additionally, mutant Escherichia coli strains carrying charge reversal radD changes display increased sensitivity to DNA damaging agents synergistically with deletions of radA and recG, although the phenotypes of the SSB-binding radD mutants are not as severe as a full radD deletion. This suggests that cellular RadD requires an intact interaction with SSB for full RadD function.


Asunto(s)
Proteínas de Unión al ADN , Escherichia coli , Adenosina Trifosfatasas/genética , Adenosina Trifosfatasas/metabolismo , Reparación del ADN/genética , ADN de Cadena Simple/genética , ADN de Cadena Simple/metabolismo , Proteínas de Unión al ADN/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Unión Proteica , Mutación , Sitios de Unión , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Modelos Moleculares , Estructura Cuaternaria de Proteína
4.
Phys Rev Lett ; 132(9): 093601, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38489641

RESUMEN

In this Letter we identify coherent electron-vibron interactions between near-resonant and nonresonant electronic levels that contribute beyond standard optomechanical models for off-resonant or resonance surface-enhanced Raman scattering (SERS). By developing an open-system quantum model using first molecular interaction principles, we show how the Raman interference of both resonant and nonresonant contributions can provide several orders of magnitude modifications of the SERS peaks with respect to former optomechanical models and over the fluorescence backgrounds. This cooperative optomechanical mechanism allows for generating an enhancement of nonclassical photon pair correlations between Stokes and anti-Stokes photons, which can be detected by photon-counting measurements. Our results demonstrate Raman enhancements and suppressions of coherent nature that significantly impact the standard estimations of the optomechanical contribution from SERS spectra and their quantum mechanical observable effects.

5.
Brain ; 146(10): 4233-4246, 2023 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-37186601

RESUMEN

In utero exposure to maternal antibodies targeting the fetal acetylcholine receptor isoform (fAChR) can impair fetal movement, leading to arthrogryposis multiplex congenita (AMC). Fetal AChR antibodies have also been implicated in apparently rare, milder myopathic presentations termed fetal acetylcholine receptor inactivation syndrome (FARIS). The full spectrum associated with fAChR antibodies is still poorly understood. Moreover, since some mothers have no myasthenic symptoms, the condition is likely underreported, resulting in failure to implement effective preventive strategies. Here we report clinical and immunological data from a multicentre cohort (n = 46 cases) associated with maternal fAChR antibodies, including 29 novel and 17 previously reported with novel follow-up data. Remarkably, in 50% of mothers there was no previously established myasthenia gravis (MG) diagnosis. All mothers (n = 30) had AChR antibodies and, when tested, binding to fAChR was often much greater than that to the adult AChR isoform. Offspring death occurred in 11/46 (23.9%) cases, mainly antenatally due to termination of pregnancy prompted by severe AMC (7/46, 15.2%), or during early infancy, mainly from respiratory failure (4/46, 8.7%). Weakness, contractures, bulbar and respiratory involvement were prominent early in life, but improved gradually over time. Facial (25/34; 73.5%) and variable peripheral weakness (14/32; 43.8%), velopharyngeal insufficiency (18/24; 75%) and feeding difficulties (16/36; 44.4%) were the most common sequelae in long-term survivors. Other unexpected features included hearing loss (12/32; 37.5%), diaphragmatic paresis (5/35; 14.3%), CNS involvement (7/40; 17.5%) and pyloric stenosis (3/37; 8.1%). Oral salbutamol used empirically in 16/37 (43.2%) offspring resulted in symptom improvement in 13/16 (81.3%). Combining our series with all previously published cases, we identified 21/85 mothers treated with variable combinations of immunotherapies (corticosteroids/intravenous immunoglobulin/plasmapheresis) during pregnancy either for maternal MG symptom control (12/21 cases) or for fetal protection (9/21 cases). Compared to untreated pregnancies (64/85), maternal treatment resulted in a significant reduction in offspring deaths (P < 0.05) and other complications, with treatment approaches involving intravenous immunoglobulin/ plasmapheresis administered early in pregnancy most effective. We conclude that presentations due to in utero exposure to maternal (fetal) AChR antibodies are more common than currently recognized and may mimic a wide range of neuromuscular disorders. Considering the wide clinical spectrum and likely diversity of underlying mechanisms, we propose 'fetal acetylcholine receptor antibody-related disorders' (FARAD) as the most accurate term for these presentations. FARAD is vitally important to recognize, to institute appropriate management strategies for affected offspring and to improve outcomes in future pregnancies. Oral salbutamol is a symptomatic treatment option in survivors.


Asunto(s)
Artrogriposis , Miastenia Gravis , Enfermedades Neuromusculares , Embarazo , Femenino , Adulto , Humanos , Inmunoglobulinas Intravenosas , Receptores Colinérgicos , Miastenia Gravis/terapia , Miastenia Gravis/complicaciones , Autoanticuerpos , Artrogriposis/complicaciones
7.
Artículo en Inglés | MEDLINE | ID: mdl-38695818

RESUMEN

OBJECTIVES: The proliferation of social media has resulted in negative consequences such as fear of missing out (FoMO), the anxious feelings one has when others are having rewarding experiences. Few studies have assessed FoMO in Latinx emerging adult college students, none utilizing the socioecological framework. This study assessed the relationships between FoMO and psychological and sociocultural risk and protective factors. METHOD: Latinx college students (n = 452; Mage = 19.97 years, SD = 1.89; 77.2% female) completed an online survey assessing demographics, FoMO, social media addiction, depression, anxiety, stress, Machiavellianism, narcissism, psychopathy, familism, and acculturation. Two multiple linear regressions assessed the associations between FoMO and psychological and sociocultural factors. RESULTS: Both regressions were statistically significant. First, FoMO was positively associated with social media addiction, depression, and Machiavellianism. Second, FoMO was positively associated with familial honor and negatively associated with familial interconnectedness and ethnic social relations. CONCLUSIONS: Associations between FoMO and psychological factors are consistent with past literature, yet they highlight the need for prospective studies to assess temporality. The fact that FoMO was related uniquely to familistic attitudes suggests the importance of family in FoMO perceptions and the need to assess these associations in a more nuanced manner. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

8.
Chromosome Res ; 30(1): 91-107, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35089455

RESUMEN

Cuscuta is a cytogenetically diverse genus, with karyotypes varying 18-fold in chromosome number and 127-fold in genome size. Each of its four subgenera also presents particular chromosomal features, such as bimodal karyotypes in Pachystigma. We used low coverage sequencing of the Cuscuta nitida genome (subgenus Pachystigma), as well as chromosome banding and molecular cytogenetics of three subgenus representatives, to understand the origin of bimodal karyotypes. All three species, C. nitida, C. africana (2n = 28) and C. angulata (2n = 30), showed heterochromatic bands mainly in the largest chromosome pairs. Eighteen satellite DNAs were identified in C. nitida genome, two showing similarity to mobile elements. The most abundant were present at the largest pairs, as well as the highly abundant ribosomal DNAs. The most abundant Ty1/Copia and Ty3/Gypsy elements were also highly enriched in the largest pairs, except for the Ty3/Gypsy CRM, which also labelled the pericentromeric regions of the smallest chromosomes. This accumulation of repetitive DNA in the larger pairs indicates that these sequences are largely responsible for the formation of bimodal karyotypes in the subgenus Pachystigma. The repetitive DNA fraction is directly linked to karyotype evolution in Cuscuta.


Asunto(s)
Cuscuta , Cuscuta/genética , ADN Ribosómico/genética , Evolución Molecular , Cariotipo , Filogenia
9.
Curr Psychol ; : 1-14, 2023 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-37359598

RESUMEN

Phubbing is when one uses their smartphone in a social interaction instead of interacting with the other individual(s) in their presence. Phubbing and being phubbed are growing concerns as the number of smartphones and frequency of smartphone use increases. This study assessed the relationships between phubbing, being phubbed, psychosocial constructs, and socially adverse personality traits among Hispanic emerging adult college students. Hispanic college students (n = 452) completed a survey assessing: sociodemographics, phubbing, being phubbed, depression, anxiety, stress, Machiavellianism, narcissism, psychopathy, and need for drama (interpersonal manipulation, impulsive outspokenness, persistent perceived victimhood). Hispanic emerging adult college students reported low-to-moderate levels of phubbing and being phubbed. Regarding phubbing findings, nomophobia (fear of separation from one's phone), interpersonal conflict, and problem acknowledgement were positively associated with negative affect. Moreover, interpersonal conflict, self-isolation, and problem acknowledgement were positively associated with interpersonal manipulation. Regarding being phubbed findings, perceived norms, feeling ignored, and interpersonal conflict were positively associated with persistent perceived victimhood. Findings indicate that Hispanic college students may use their smartphones in social settings to alleviate negative affect. Moreover, a virtual environment on a smartphone may be easier to manipulate and can be used to continue garnering attention and portraying oneself as the victim, fulfilling one's need for drama. Regarding exploratory mediations, phubbing and being phubbed mediated the relationships between multiple socially adverse personality traits and negative affect. The clinical implications of these results are discussed. Prospective studies are warranted to determine temporality. Supplementary information: The online version contains supplementary material available at 10.1007/s12144-023-04767-y.

10.
Microb Pathog ; 170: 105718, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35961485

RESUMEN

Scedosporium apiospermum is an opportunistic pathogen that can cause pulmonary infections in both immunosuppressive and immunocompetent patients. Cytokines are molecules that mediate the immune response to promote or eliminate fungal infections. In this work, we evaluated the cytokines profile in the lung and serum of mice infected with Scedosporium apiospermum. We found early production of IL-6, IL-1ß and TNF-α cytokines in the lung of infected mice during the first 5 days of infection. We suggest that release of pro-inflammatory cytokines could play a role in the control of fungal invasion.


Asunto(s)
Micosis , Neumonía , Scedosporium , Animales , Antifúngicos/uso terapéutico , Citocinas , Pulmón , Ratones , Micosis/tratamiento farmacológico , Neumonía/tratamiento farmacológico
11.
FEMS Yeast Res ; 22(1)2022 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-35488874

RESUMEN

Pichia pastoris has been widely used to produce antigenic proteins aimed to integrate subunit vaccines. Moreover, increasing interest in large-scale vaccine production at the lowest cost is rapidly focusing in the development of yeast surface display (YSD) systems for delivery of antigens. In this scenario, the safety of live yeast administration must be warranted, however, such information is very scarce. Here, we assess the intravenous administration (i.v.) of live P. pastoris cells in order to trace dissemination in BALB/c mice and to evaluate the immune response raised against the yeast compared to the well-defined pathogen Candida albicans. Our results demonstrate dissemination of P. pastoris to the heart, kidney, and spleen, but it is quickly eliminated during the first 48 h postinfection (hpi), with persistence in the liver along with mild mononuclear (MN) and polymorphonuclear (PMN) infiltrate, which was resolved at 144 hpi. In vivo delayed-type hypersensitivity test (DTH) or in vitro antigenic stimulation of mice splenocytes demonstrate that transient infection of P. pastoris did not induce a cell-mediated immune response nor increase the level of circulating IgG or IgM. These results demonstrate the innocuous profile of P. pastoris and support its use as a safe delivery system for vaccine development.


Asunto(s)
Pichia , Saccharomycetales , Administración Intravenosa , Animales , Ratones , Ratones Endogámicos BALB C , Pichia/metabolismo
12.
Am J Med Genet A ; 188(9): 2783-2789, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35616428

RESUMEN

Biallelic pathogenic variants in phosphopantothenoylcysteine synthetase, PPCS, are a rare cause of a severe early-onset dilated cardiomyopathy with high morbidity and mortality. To date, only five individuals with PPCS-mutations have been reported. Here, we report a female infant who presented in the neonatal period with hypotonia, a necrotizing myopathy with intermittent rhabdomyolysis and other extracardiac manifestations before developing a progressive and ultimately fatal dilated cardiomyopathy. Gene agnostic trio genome sequencing revealed two rare variants in the PPCS [MIM: 609853] in trans, a previously reported pathogenic c.320_334del p. (Pro107_Ala111del) variant, and a c.613-3C>G intronic variant of uncertain significance. Functional studies confirmed the likely pathogenicity of this variant. Our case provides clinical and histopathological evidence for an associated neuromuscular phenotype not previously recognized and expands the evolving phenotypic spectrum of PPCS-related disorders. We also performed a literature search of all previously published cases and summarize the common features.


Asunto(s)
Cardiomiopatía Dilatada , Cardiomiopatía Dilatada/genética , Femenino , Humanos , Mutación
13.
Int J Legal Med ; 136(2): 565-567, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34613462

RESUMEN

With the advent of expanded STR (short tandem repeats) typing kits, it was necessary to determine allele frequencies and other appropriate population data parameters for El Salvador. Samples were collected from the central, east, and west regions of the country and typed for 21 forensically relevant STR loci. The data indicate that all loci are highly polymorphic, the three regions are genetically similar, and the population data are similar to those of US Hispanics. The results of this study support that the allele frequency data described herein can be used for statistical calculations for human identity testing in El Salvador.


Asunto(s)
Dermatoglifia del ADN , Genética de Población , Frecuencia de los Genes , Hispánicos o Latinos , Humanos , Repeticiones de Microsatélite
14.
Brain ; 144(2): 584-600, 2021 03 03.
Artículo en Inglés | MEDLINE | ID: mdl-33559681

RESUMEN

The extracellular matrix comprises a network of macromolecules such as collagens, proteoglycans and glycoproteins. VWA1 (von Willebrand factor A domain containing 1) encodes a component of the extracellular matrix that interacts with perlecan/collagen VI, appears to be involved in stabilizing extracellular matrix structures, and demonstrates high expression levels in tibial nerve. Vwa1-deficient mice manifest with abnormal peripheral nerve structure/function; however, VWA1 variants have not previously been associated with human disease. By interrogating the genome sequences of 74 180 individuals from the 100K Genomes Project in combination with international gene-matching efforts and targeted sequencing, we identified 17 individuals from 15 families with an autosomal-recessive, non-length dependent, hereditary motor neuropathy and rare biallelic variants in VWA1. A single disease-associated allele p.(G25Rfs*74), a 10-bp repeat expansion, was observed in 14/15 families and was homozygous in 10/15. Given an allele frequency in European populations approaching 1/1000, the seven unrelated homozygote individuals ascertained from the 100K Genomes Project represents a substantial enrichment above expected. Haplotype analysis identified a shared 220 kb region suggesting that this founder mutation arose >7000 years ago. A wide age-range of patients (6-83 years) helped delineate the clinical phenotype over time. The commonest disease presentation in the cohort was an early-onset (mean 2.0 ± 1.4 years) non-length-dependent axonal hereditary motor neuropathy, confirmed on electrophysiology, which will have to be differentiated from other predominantly or pure motor neuropathies and neuronopathies. Because of slow disease progression, ambulation was largely preserved. Neurophysiology, muscle histopathology, and muscle MRI findings typically revealed clear neurogenic changes with single isolated cases displaying additional myopathic process. We speculate that a few findings of myopathic changes might be secondary to chronic denervation rather than indicating an additional myopathic disease process. Duplex reverse transcription polymerase chain reaction and immunoblotting using patient fibroblasts revealed that the founder allele results in partial nonsense mediated decay and an absence of detectable protein. CRISPR and morpholino vwa1 modelling in zebrafish demonstrated reductions in motor neuron axonal growth, synaptic formation in the skeletal muscles and locomotive behaviour. In summary, we estimate that biallelic variants in VWA1 may be responsible for up to 1% of unexplained hereditary motor neuropathy cases in Europeans. The detailed clinical characterization provided here will facilitate targeted testing on suitable patient cohorts. This novel disease gene may have previously evaded detection because of high GC content, consequential low coverage and computational difficulties associated with robustly detecting repeat-expansions. Reviewing previously unsolved exomes using lower QC filters may generate further diagnoses.


Asunto(s)
Proteínas de la Matriz Extracelular/genética , Neuropatía Hereditaria Motora y Sensorial/genética , Adulto , Anciano , Animales , Conducta Animal/fisiología , Niño , Femenino , Neuropatía Hereditaria Motora y Sensorial/patología , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/patología , Mutación , Linaje , Adulto Joven , Pez Cebra
15.
J Reconstr Microsurg ; 38(5): 378-389, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34454408

RESUMEN

BACKGROUND: Studies reporting on the deep circumflex iliac artery (DCIA) free flap are restricted to a limited number of patients and areas of application. The aim of this review was to assess the reliability and versatility of the DCIA free flap during reconstruction. METHODS: A comprehensive review was conducted in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) guidelines using PubMed, Web of Science, Cochrane CENTRAL, and SCOPUS. A critical analysis of pooled data was performed to assess outcomes employing the DCIA free flap. RESULTS: A total of 445 DCIA free flaps were included. The main recipient sites were head and neck (72.35%), lower extremity (20.67%), and upper extremity (6.74%). The main indications for reconstruction were tumor resection (73.8%) and trauma (17.43%). Fifty non-DCIA flaps were required to finalize the reconstruction of several defects. The pooled flap failure rate using the DCIA free flap was 4% (95% confidence interval: 1-8%). No significant heterogeneity was present across studies (Q statistic 22.12, p = 0.14; I 2 = 27.68%, p = 0.139). Complication rates for head and neck and limb reconstruction were 57.37 and 40.16%, respectively. The average length and surface area of bone flaps were 7.79 cm and 22.8 cm2, respectively. The area of the skin paddles was 117 cm2. CONCLUSION: The DCIA free flap has shown to be a versatile reconstructive alternative for head and neck and short-medium size limb defects. However, the complexity of functions, the recipient site location, and a potential large defect can detract from the use of the DCIA free flap as an initial reconstructive option for head and neck and extensive limb defects.


Asunto(s)
Colgajos Tisulares Libres , Procedimientos de Cirugía Plástica , Colgajos Tisulares Libres/cirugía , Humanos , Arteria Ilíaca/cirugía , Complicaciones Posoperatorias/cirugía , Reproducibilidad de los Resultados , Estudios Retrospectivos
16.
Acta Neuropathol ; 141(3): 431-453, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33449170

RESUMEN

Mutations in the sarcomeric protein titin, encoded by TTN, are emerging as a common cause of myopathies. The diagnosis of a TTN-related myopathy is, however, often not straightforward due to clinico-pathological overlap with other myopathies and the prevalence of TTN variants in control populations. Here, we present a combined clinico-pathological, genetic and biophysical approach to the diagnosis of TTN-related myopathies and the pathogenicity ascertainment of TTN missense variants. We identified 30 patients with a primary TTN-related congenital myopathy (CM) and two truncating variants, or one truncating and one missense TTN variant, or homozygous for one TTN missense variant. We found that TTN-related myopathies show considerable overlap with other myopathies but are strongly suggested by a combination of certain clinico-pathological features. Presentation was typically at birth with the clinical course characterized by variable progression of weakness, contractures, scoliosis and respiratory symptoms but sparing of extraocular muscles. Cardiac involvement depended on the variant position. Our biophysical analyses demonstrated that missense mutations associated with CMs are strongly destabilizing and exert their effect when expressed on a truncating background or in homozygosity. We hypothesise that destabilizing TTN missense mutations phenocopy truncating variants and are a key pathogenic feature of recessive titinopathies that might be amenable to therapeutic intervention.


Asunto(s)
Conectina/genética , Miotonía Congénita/diagnóstico , Miotonía Congénita/genética , Miotonía Congénita/patología , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Mutación Missense , Adulto Joven
17.
Microb Pathog ; 161(Pt B): 105285, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34774701

RESUMEN

Candida auris is an emerging multidrug resistant fungal pathogen, which represents a major challenge for newborns systemic infections worldwide. Management of C. auris infections is complicated due to its intrinsic antifungal resistance and the limited information available on its pathogenesis, particularly during neonatal period. In this study, we developed a murine model of C. auris neonatal invasive infection. C. auris dissemination was evaluated by fungal burden and histopathological analysis of lung, brain, liver, kidney, and spleen at different time intervals. We found fungal cells in all the analyzed tissues, neonatal liver and brain were the most susceptible tissues to fungal invasion. This model will help to better understand pathogenesis mechanisms and facilitate strategies for control and prevention of C. auris infections in newborns.


Asunto(s)
Candida , Candidiasis Invasiva , Animales , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Candida auris , Candidiasis Invasiva/tratamiento farmacológico , Farmacorresistencia Fúngica , Ratones , Pruebas de Sensibilidad Microbiana
18.
Microb Pathog ; 158: 105061, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34157411

RESUMEN

Invasive candidiasis is associated with a high incidence and mortality rates in infants, especially in preterm newborns. The immunopathogenesis of the mycosis during the neonatal period is poorly understood. Although several in vivo models exist to study invasive candidiasis, the majority of studies employ distinct routes of infection and use 2 to 6 day-old mice that could be less comparable in studying candidiasis in preterm infants. In this study, by using 0-days-old mice we developed a new neonatal murine model of intravenous Candida albicans infection. Using different inoculums of Candida albicans we evaluated survival, dissemination of the fungus, frequency of CD45+ cells, and cytokine production in the liver, brain, and kidneys of newborn and adult BALB/c mice. Unexpectedly, the newborn mice infected with a low inoculum (1×105 cfu per mouse) of Candida albicans survive to the infection. Compared to adult mice, the liver and brain of newborn animals had the greatest fungal burden, fungal invasion and leukocyte infiltrate. A moderate production of TNFα, IL-1ß, IL-6 and IFNγ was detected in tissues of newborn mice infected with a non-lethal inoculum of Candida albicans. In contrast, overproduction of TNFα, IL-1ß, IL-6 and IL-10 was determined when injecting with a lethal inoculum. In agreement, flow cytometry of brain and liver showed an inoculum-dependent CD45+ leukocyte infiltration in newborn mice infected with Candida albicans. Overall, our data shows that Candida albicans infection in newborn mice affects mainly the brain and liver and a 2-fold increase of the inoculum rapidly becomes lethal probably due to massive fungal invasion and exacerbated CD45+ leukocyte infiltrate and cytokine production. This study is the first analysis of innate immune responses in different tissues during early neonatal disseminated candidiasis.


Asunto(s)
Candidiasis , Inmunidad Innata , Animales , Humanos , Recién Nacido , Ratones , Candida albicans , Candidiasis/inmunología , Recien Nacido Prematuro , Ratones Endogámicos BALB C
19.
Med Mycol ; 59(10): 1006-1014, 2021 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-34021564

RESUMEN

This study aimed to assess the species distribution and antifungal susceptibility patterns of 200 strains of Aspergillus isolated from clinical specimens (n = 146) and soil samples (n = 54) in Mexico. ITS, ß-tubulin, and calmodulin DNA sequencing was performed for species identification. Broth microdilution susceptibility testing for amphotericin B, voriconazole, posaconazole, itraconazole, isavuconazole, anidulafungin, caspofungin, and micafungin was done according to CLSI for all strains. A. fumigatus was most frequently recovered from clinical specimens, while A. niger was commonly encountered in soil, both followed by A. flavus in the second place. A total of 60 (30%) cryptic species were identified, with A. tubingensis and A. tamarii being the most commonly found. The decreased susceptibility to amphotericin B and azoles was 32% for both, and were mainly led by A. fumigatus, whereas this percentage decreased to 9% for caspofungin, particularly in A. terreus. More than 75% of cryptic species were susceptible in vitro to all antifungals. Multi-azole decreased susceptibility was detected only in seven isolates. Given that antifungal resistance in Aspergillus spp. is an increasing worldwide threat that causes major challenges in the clinical management of aspergillosis, these data highlight the need for continuous epidemiological surveillance of these pathogens for the implementation of locally adequate treatment strategies. LAY SUMMARY: This is an epidemiological study in Mexico. A. fumigatus was most frequent in clinical specimens and A. niger in soil samples. A. tubingensis and A. tamarii were the most common cryptic species. Resistance to amphotericin B and azoles was 32% each, and 9% for caspofungin.


Asunto(s)
Antifúngicos , Aspergillus , Animales , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , México/epidemiología , Pruebas de Sensibilidad Microbiana/veterinaria , Suelo , Voriconazol
20.
J Oncol Pharm Pract ; 27(7): 1753-1757, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33356885

RESUMEN

INTRODUCTION: Cerebellar mutism syndrome (CMS) is a common complication after posterior fossa tumor resection. It is characterized by a significant lack or loss of speech. Its biological origin remains unclear and there are no standardized treatments. However, bromocriptine seems to be a possible treatment for this condition. CASE REPORT: In this paper, we present three cases of pediatric patients (4, 5, and 17-year old) who developed CMS after posterior fossa tumor surgery. They were treated with bromocriptine to improve neurological symptoms.Management and outcome: Bromocriptine was started at a low dose and was progressively increased to reach the minimum effective dose. After four months of treatment, a normal and fluid speech was observed in the three patients. No discontinuation due to adverse events were reported. DISCUSSION: Bromocriptine has shown to be an effective and safe treatment for CMS in pediatric patients after posterior fossa tumor resection.


Asunto(s)
Neoplasias Cerebelosas , Neoplasias Infratentoriales , Meduloblastoma , Mutismo , Bromocriptina/uso terapéutico , Neoplasias Cerebelosas/tratamiento farmacológico , Neoplasias Cerebelosas/cirugía , Niño , Humanos , Mutismo/tratamiento farmacológico , Mutismo/etiología , Complicaciones Posoperatorias/tratamiento farmacológico
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