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1.
Am J Med Genet A ; 194(4): e63473, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37964495

RESUMEN

Ophthalmological conditions are underreported in patients with KBG syndrome, which is classically described as presenting with dental, developmental, intellectual, skeletal, and craniofacial abnormalities. This study analyzed the prevalence of four ophthalmological conditions (strabismus, astigmatism, myopia, hyperopia) in 43 patients with KBG syndrome carrying variants in ANKRD11 or deletions in 16q24.3 and compared it to the literature. Forty-three patients were recruited via self-referral or a private Facebook group hosted by the KBG Foundation, with 40 of them having pathogenic or likely pathogenic variants. Virtual interviews were conducted to collect a comprehensive medical history verified by medical records. From these records, data analysis was performed to calculate the prevalence of ophthalmological conditions. Out of the 40 participants with pathogenic or likely pathogenic variants, strabismus was reported in 9 (22.5%) participants, while astigmatism, myopia, and hyperopia were reported in 11 (27.5%), 6 (15.0%), and 8 (20.0%) participants, respectively. Other reported conditions include anisometropia, amblyopia, and nystagmus. When compared to the literature, the prevalence of strabismus and refractive errors is higher than other studies. However, more research is needed to determine if variants in ANKRD11 play a role in abnormal development of the visual system. In patients with established KBG syndrome, screening for misalignment or refractive errors should be done, as interventions in patients with these conditions can improve functioning and quality of life.


Asunto(s)
Anomalías Múltiples , Astigmatismo , Enfermedades del Desarrollo Óseo , Hiperopía , Discapacidad Intelectual , Miopía , Errores de Refracción , Estrabismo , Anomalías Dentarias , Humanos , Anomalías Múltiples/diagnóstico , Discapacidad Intelectual/diagnóstico , Enfermedades del Desarrollo Óseo/diagnóstico , Anomalías Dentarias/epidemiología , Anomalías Dentarias/genética , Anomalías Dentarias/diagnóstico , Facies , Hiperopía/epidemiología , Hiperopía/genética , Calidad de Vida , Errores de Refracción/epidemiología , Errores de Refracción/genética , Errores de Refracción/diagnóstico , Factores de Transcripción , Miopía/diagnóstico , Miopía/epidemiología , Miopía/genética
2.
Am J Respir Crit Care Med ; 204(6): 692-702, 2021 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-34170795

RESUMEN

Rationale: Although it is clear that cystic fibrosis (CF) airway disease begins at a very young age, the early and subsequent steps in disease pathogenesis and the relative contribution of infection, mucus, and inflammation are not well understood. Objectives: As one approach to assessing the early contribution of infection, we tested the hypothesis that early and continuous antibiotics would decrease the airway bacterial burden. We believed that, if they do, this might reveal aspects of the disease that are more or less sensitive to decreasing infection. Methods: Three groups of pigs were studied from birth until ∼3 weeks of age: 1) wild-type, 2) CF, and 3) CF pigs treated continuously with broad-spectrum antibiotics from birth until study completion. Disease was assessed with chest computed tomography, histopathology, microbiology, and BAL. Measurements and Main Results: Disease was present by 3 weeks of age in CF pigs. Continuous antibiotics from birth improved chest computed tomography imaging abnormalities and airway mucus accumulation but not airway inflammation in the CF pig model. However, reducing bacterial infection did not improve two disease features already present at birth in CF pigs: air trapping and submucosal gland duct plugging. In the CF sinuses, antibiotics did not prevent the development of infection or disease or the number of bacteria but did alter the bacterial species. Conclusions: These findings suggest that CF airway disease begins immediately after birth and that early and continuous antibiotics impact some, but not all, aspects of CF lung disease development.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Fibrosis Quística/tratamiento farmacológico , Fibrosis Quística/microbiología , Pulmón/efectos de los fármacos , Mucosa Respiratoria/efectos de los fármacos , Animales , Antibacterianos/uso terapéutico , Bacterias/aislamiento & purificación , Líquido del Lavado Bronquioalveolar/microbiología , Fibrosis Quística/diagnóstico por imagen , Fibrosis Quística/patología , Pulmón/diagnóstico por imagen , Pulmón/microbiología , Pulmón/patología , Tomografía Computarizada Multidetector , Mucosa Respiratoria/microbiología , Mucosa Respiratoria/patología , Porcinos
3.
Phytopathology ; 110(11): 1759-1762, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32539638

RESUMEN

Xylella fastidiosa is a xylem-limited bacterial plant pathogen that causes disease on numerous hosts. Additionally, X. fastidiosa asymptomatically colonizes a wide range of plant species. X. fastidiosa subsp. multiplex has been detected in olive (Olea europaea) trees grown in California, U.S.A., as well as in Europe. Strains of X. fastidiosa subsp. multiplex isolated from California olive trees are not known to cause disease on olive, although some can induce leaf-scorch symptoms on almond (Prunus dulcis). No genome assemblies currently exist for olive-associated X. fastidiosa subsp. multiplex strains; therefore, a hybrid assembly method was used to generate complete genome sequences for three X. fastidiosa subsp. multiplex strains (Fillmore, LM10, and RH1) isolated from olive trees grown in Ventura and Los Angeles counties of California.


Asunto(s)
Olea , Xylella , California , Europa (Continente) , Enfermedades de las Plantas , Xylella/genética
4.
Proc Natl Acad Sci U S A ; 114(26): 6842-6847, 2017 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-28607090

RESUMEN

Gel-forming mucins, the primary macromolecular components of airway mucus, facilitate airway clearance by mucociliary transport. In cystic fibrosis (CF) altered mucus properties impair mucociliary transport. Airways primarily secrete two closely related gel-forming mucins, MUC5B and MUC5AC. However, their morphologic structures and associations in airways that contain abundant submucosal glands and goblet cells are uncertain. Moreover, there is limited knowledge about mucins in airways not affected by inflammation, infection, or remodeling or in CF airways. Therefore, we examined airways freshly excised from newborn non-CF pigs and CF pigs before secondary manifestations develop. We found that porcine submucosal glands produce MUC5B, whereas goblet cells produce predominantly MUC5AC plus some MUC5B. We found that MUC5B emerged from submucosal gland ducts in the form of strands composed of multiple MUC5B filaments. In contrast, MUC5AC emerged from goblet cells as wispy threads and sometimes formed mucin sheets. In addition, MUC5AC often partially coated the MUC5B strands. Compared with non-CF, MUC5B more often filled CF submucosal gland ducts. MUC5AC sheets also accumulated in CF airways overlying MUC5B strands. These results reveal distinct morphology and interactions for MUC5B and MUC5AC and suggest that the two mucins make distinct contributions to mucociliary transport. Thus, they provide a framework for understanding abnormalities in disease.


Asunto(s)
Remodelación de las Vías Aéreas (Respiratorias) , Fibrosis Quística/metabolismo , Células Caliciformes/metabolismo , Mucina 5AC/metabolismo , Mucina 5B/metabolismo , Animales , Fibrosis Quística/genética , Fibrosis Quística/patología , Células Caliciformes/patología , Ratones , Ratones Noqueados , Mucina 5AC/genética , Mucina 5B/genética
5.
Plant Dis ; 104(11): 2994-3001, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32852243

RESUMEN

Xylella fastidiosa is a vector-transmitted bacterial plant pathogen that affects a wide array of perennial crops, including grapevines (Pierce's disease). In the southern San Joaquin Valley of California, epidemics of Pierce's disease of grapevine were associated with the glassy-winged sharpshooter, Homalodisca vitripennis. During the growing season, rates of X. fastidiosa spread in vineyards are affected by changes in pathogen distribution within chronically infected grapevines and by vector population dynamics. Grapevines chronically infected with X. fastidiosa rarely tested positive for the pathogen prior to July, suggesting vector acquisition of X. fastidiosa from grapevines increases as the season progresses. This hypothesis was supported by an increase in number of X. fastidiosa-positive glassy-winged sharpshooters collected from vineyards during July through September. Analysis of insecticide records indicated that vineyards in the study area were typically treated with a systemic neonicotinoid in spring of each year. As a result, abundance of glassy-winged sharpshooters was typically low in late spring and early summer, with abundance of glassy-winged sharpshooter adults increasing in late June and early July of each year. Collectively, the results suggest that late summer is a crucial time for X. fastidiosa secondary spread in vineyards in the southern San Joaquin Valley, because glassy-winged sharpshooter abundance, number of glassy-winged sharpshooters testing positive for X. fastidiosa, and grapevines with detectable pathogen populations were all greatest during this period.


Asunto(s)
Xylella , Animales , California , Enfermedades de las Plantas , Dinámica Poblacional
6.
Appl Environ Microbiol ; 85(13)2019 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-31028021

RESUMEN

Xylella fastidiosa is an economically important bacterial plant pathogen. With insights gained from 72 genomes, this study investigated differences among the three main subspecies, which have allopatric origins: X. fastidiosa subsp. fastidiosa, multiplex, and pauca The origin of recombinogenic X. fastidiosa subsp. morus and sandyi was also assessed. The evolutionary rate of the 622 genes of the species core genome was estimated at the scale of an X. fastidiosa subsp. pauca subclade (7.62 × 10-7 substitutions per site per year), which was subsequently used to estimate divergence time for the subspecies and introduction events. The study characterized genes present in the accessory genome of each of the three subspecies and investigated the core genome to detect genes potentially under positive selection. Recombination is recognized to be the major driver of diversity in X. fastidiosa, potentially facilitating shifts to novel plant hosts. The relative effect of recombination in comparison to point mutation was calculated (r/m = 2.259). Evidence of recombination was uncovered in the core genome alignment; X. fastidiosa subsp. fastidiosa in the United States was less prone to recombination, with an average of 3.22 of the 622 core genes identified as recombining regions, whereas a specific clade of X. fastidiosa subsp. multiplex was found to have on average 9.60 recombining genes, 93.2% of which originated from X. fastidiosa subsp. fastidiosa Interestingly, for X. fastidiosa subsp. morus, which was initially thought to be the outcome of genome-wide recombination between X. fastidiosa subsp. fastidiosa and X. fastidiosa subsp. multiplex, intersubspecies homologous recombination levels reached 15.30% in the core genome. Finally, there is evidence of X. fastidiosa subsp. pauca strains from citrus containing genetic elements acquired from strains infecting coffee plants as well as genetic elements from both X. fastidiosa subsp. fastidiosa and X. fastidiosa subsp. multiplex In summary, our data provide new insights into the evolution and epidemiology of this plant pathogen.IMPORTANCEXylella fastidiosa is an important vector-borne plant pathogen. We used a set of 72 genomes that constitutes the largest assembled data set for this bacterial species so far to investigate genetic relationships and the impact of recombination on phylogenetic clades and to compare genome content at the subspecies level, and we used a molecular dating approach to infer the evolutionary rate of X. fastidiosa The results demonstrate that recombination is important in shaping the genomes of X. fastidiosa and that each of the main subspecies is under different selective pressures. We hope insights from this study will improve our understanding of X. fastidiosa evolution and biology.


Asunto(s)
Variación Genética , Genoma Bacteriano , Recombinación Homóloga , Xylella/genética , Filogenia
7.
Phytopathology ; 107(4): 388-394, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27938243

RESUMEN

Xylella fastidiosa, the causal agent of Pierce's disease of grapes, is a slow-growing, xylem-limited, bacterial pathogen. Disease progression is characterized by systemic spread of the bacterium through xylem vessel networks, causing leaf-scorching symptoms, senescence, and vine decline. It appears to be advantageous to this pathogen to avoid excessive blockage of xylem vessels, because living bacterial cells are generally found in plant tissue with low bacterial cell density and minimal scorching symptoms. The DinJ/RelE toxin-antitoxin system is characterized here for a role in controlling bacterial proliferation and population size during plant colonization. The DinJ/RelE locus is transcribed from two separate promoters, allowing for coexpression of antitoxin DinJ with endoribonuclease toxin RelE, in addition to independent expression of RelE. The ratio of antitoxin/toxin expressed is dependent on bacterial growth conditions, with lower amounts of antitoxin present under conditions designed to mimic grapevine xylem sap. A knockout mutant of DinJ/RelE exhibits a hypervirulent phenotype, with higher bacterial populations and increased symptom development and plant decline. It is likely that DinJ/RelE acts to prevent excessive population growth, contributing to the ability of the pathogen to spread systemically without completely blocking the xylem vessels and increasing probability of acquisition by the insect vector.


Asunto(s)
Antitoxinas/metabolismo , Proteínas Bacterianas/metabolismo , Toxinas Bacterianas/metabolismo , Enfermedades de las Plantas/inmunología , Vitis/inmunología , Xylella/genética , Animales , Antitoxinas/genética , Proteínas Bacterianas/genética , Toxinas Bacterianas/genética , Técnicas de Inactivación de Genes , Interacciones Huésped-Patógeno , Insectos Vectores/microbiología , Operón/genética , Enfermedades de las Plantas/microbiología , Hojas de la Planta/microbiología , Regiones Promotoras Genéticas/genética , Virulencia , Vitis/microbiología , Xylella/crecimiento & desarrollo , Xylella/patogenicidad , Xilema/microbiología
8.
Am J Respir Crit Care Med ; 193(4): 417-26, 2016 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-26488271

RESUMEN

RATIONALE: An asthma-like airway phenotype has been described in people with cystic fibrosis (CF). Whether these findings are directly caused by loss of CF transmembrane conductance regulator (CFTR) function or secondary to chronic airway infection and/or inflammation has been difficult to determine. OBJECTIVES: Airway contractility is primarily determined by airway smooth muscle. We tested the hypothesis that CFTR is expressed in airway smooth muscle and directly affects airway smooth muscle contractility. METHODS: Newborn pigs, both wild type and with CF (before the onset of airway infection and inflammation), were used in this study. High-resolution immunofluorescence was used to identify the subcellular localization of CFTR in airway smooth muscle. Airway smooth muscle function was determined with tissue myography, intracellular calcium measurements, and regulatory myosin light chain phosphorylation status. Precision-cut lung slices were used to investigate the therapeutic potential of CFTR modulation on airway reactivity. MEASUREMENTS AND MAIN RESULTS: We found that CFTR localizes to the sarcoplasmic reticulum compartment of airway smooth muscle and regulates airway smooth muscle tone. Loss of CFTR function led to delayed calcium reuptake following cholinergic stimulation and increased myosin light chain phosphorylation. CFTR potentiation with ivacaftor decreased airway reactivity in precision-cut lung slices following cholinergic stimulation. CONCLUSIONS: Loss of CFTR alters porcine airway smooth muscle function and may contribute to the airflow obstruction phenotype observed in human CF. Airway smooth muscle CFTR may represent a therapeutic target in CF and other diseases of airway narrowing.


Asunto(s)
Regulador de Conductancia de Transmembrana de Fibrosis Quística/fisiología , Contracción Muscular/fisiología , Músculo Liso/fisiopatología , Retículo Sarcoplasmático/fisiología , Animales , Animales Recién Nacidos , Western Blotting , Técnica del Anticuerpo Fluorescente , Pulmón/fisiopatología , Modelos Animales , Porcinos
9.
Mol Plant Microbe Interact ; 29(5): 335-44, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26808446

RESUMEN

Xylella fastidiosa, causal agent of Pierce's disease (PD) of grapevine, is a fastidious organism that requires very specific conditions for replication and plant colonization. Cold temperatures reduce growth and survival of X. fastidiosa both in vitro and in planta. However, little is known regarding physiological responses of X. fastidiosa to temperature changes. Cold-shock proteins (CSP), a family of nucleic acid-binding proteins, act as chaperones facilitating translation at low temperatures. Bacterial genomes often encode multiple CSP, some of which are strongly induced following exposure to cold. Additionally, CSP contribute to the general stress response through mRNA stabilization and posttranscriptional regulation. A putative CSP homolog (Csp1) with RNA-binding activity was identified in X. fastidiosa Stag's Leap. The csp1 gene lacked the long 5' untranslated region characteristic of cold-inducible genes and was expressed in a temperature-independent manner. As compared with the wild type, a deletion mutant of csp1 (∆csp1) had decreased survival rates following cold exposure and salt stress in vitro. The deletion mutant also was significantly less virulent in grapevine, as compared with the wild type, in the absence of cold stress. These results suggest an important function of X. fastidiosa Csp1 in response to cellular stress and during plant colonization.


Asunto(s)
Proteínas Bacterianas/metabolismo , Proteínas y Péptidos de Choque por Frío/metabolismo , Regulación Bacteriana de la Expresión Génica/fisiología , Factores de Virulencia/metabolismo , Xylella/metabolismo , Adaptación Fisiológica , Proteínas Bacterianas/genética , Proteínas y Péptidos de Choque por Frío/genética , Frío , Proteínas de la Membrana , Datos de Secuencia Molecular , Mutación , Proteínas de Saccharomyces cerevisiae , Estrés Fisiológico , Factores de Virulencia/genética , Vitis/microbiología
10.
Phytopathology ; 106(8): 928-36, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27088393

RESUMEN

The phytopathogen Xylella fastidiosa causes disease in a variety of important crop and landscape plants. Functional genetic studies have led to a broader understanding of virulence mechanisms used by this pathogen in the grapevine host. Plasmid shuttle vectors are important tools in studies of bacterial genetics but there are only a limited number of plasmid vectors available that replicate in X. fastidiosa, and even fewer that are retained without antibiotic selection. Two plasmids are described here that show stable replication in X. fastidiosa and are effective for gene complementation both in vitro and in planta. Plasmid maintenance is facilitated by incorporation of the PemI/PemK plasmid addiction system, consisting of PemK, an endoribonuclease toxin, and its cognate antitoxin, PemI. Vector pXf20pemIK utilizes a native X. fastidiosa replication origin as well as a high-copy-number pUC origin for propagation in Escherichia coli cloning strains. Broad-host-range vector pBBR5pemIK is a medium- to low-copy-number plasmid based on the pBBR1 backbone. Both plasmids are maintained for extended periods of time in the absence of antibiotic selection, as well as up to 14 weeks in grapevine, without affecting bacterial fitness. These plasmids present an alternative to traditional complementation and expression vectors which rely on antibiotic selection for plasmid retention.


Asunto(s)
Antitoxinas/metabolismo , Toxinas Bacterianas/metabolismo , Vectores Genéticos , Plásmidos , Xylella/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , ADN Bacteriano/genética , Regulación Bacteriana de la Expresión Génica/fisiología , Transformación Bacteriana , Vitis/microbiología
11.
J Econ Entomol ; 109(2): 487-501, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26637536

RESUMEN

Models on the spread of insect-transmitted plant pathogens often fix vector population size by assuming that deaths are offset by births. Although such mathematical simplifications are often justified, deemphasizing parameters that govern vector population size is problematic, as reproductive biology and mortality schedules of vectors of plant pathogens receive little empirical attention. Here, the importance of explicitly including parameters for vector birth and death rates was evaluated by comparing results from models with fixed vector population size with models with logistic vector population growth. In fixed vector population size models, increasing vector mortality decreased percentage of inoculative vectors, but had no effect on vector population size, as deaths were offset by births. In models with logistic vector population growth, increasing vector mortality decreased percentage of inoculative vectors and decreased vector population size. Consequently, vector mortality had a greater effect on pathogen spread in models with logistic vector population growth than in models with fixed vector population size. Further, in models with logistic vector population growth, magnitude of vector birth rate determined time required for vector populations to reach large size, thereby determining when pathogen spread occurred quickly. Assumptions regarding timing of vector mortality within a time step also affected model outcome. A greater emphasis of vector entomologists on studying reproductive biology and mortality schedules of insect species that transmit plant pathogens will facilitate identification of conditions associated with rapid growth of vector populations and could lead to development of novel control strategies.


Asunto(s)
Insectos Vectores , Modelos Biológicos , Enfermedades de las Plantas , Animales , Mortalidad , Densidad de Población , Dinámica Poblacional
12.
Ann Oncol ; 26(8): 1589-604, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26041764

RESUMEN

The first St Gallen Advanced Prostate Cancer Consensus Conference (APCCC) Expert Panel identified and reviewed the available evidence for the ten most important areas of controversy in advanced prostate cancer (APC) management. The successful registration of several drugs for castration-resistant prostate cancer and the recent studies of chemo-hormonal therapy in men with castration-naïve prostate cancer have led to considerable uncertainty as to the best treatment choices, sequence of treatment options and appropriate patient selection. Management recommendations based on expert opinion, and not based on a critical review of the available evidence, are presented. The various recommendations carried differing degrees of support, as reflected in the wording of the article text and in the detailed voting results recorded in supplementary Material, available at Annals of Oncology online. Detailed decisions on treatment as always will involve consideration of disease extent and location, prior treatments, host factors, patient preferences as well as logistical and economic constraints. Inclusion of men with APC in clinical trials should be encouraged.


Asunto(s)
Adenocarcinoma/terapia , Antagonistas de Andrógenos/uso terapéutico , Antineoplásicos Hormonales/uso terapéutico , Conservadores de la Densidad Ósea/uso terapéutico , Neoplasias de la Próstata Resistentes a la Castración/terapia , Neoplasias de la Próstata/terapia , Taxoides/uso terapéutico , Adenocarcinoma/patología , Antineoplásicos/uso terapéutico , Docetaxel , Humanos , Masculino , Orquiectomía , Guías de Práctica Clínica como Asunto , Prostatectomía , Neoplasias de la Próstata/patología , Neoplasias de la Próstata Resistentes a la Castración/patología , Radioterapia Adyuvante
13.
J Econ Entomol ; 108(3): 1014-24, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26470224

RESUMEN

The glassy-winged sharpshooter (Homalodisca vitripennis) is synovigenic and must feed as an adult to produce eggs. Egg maturation rates depend on the host plant species provided to the adult female for feeding and are variable for females provided with the same host plant species. Here, the contribution of female size and lipid content to variation in egg maturation rates among females held on the same host plant species was assessed. To assess effects of female size and lipid content on egg maturation, feeding assays followed by measurements of egg load, female size, and lipid content were conducted. To accomplish this, females were field collected and held on cowpea until producing approximately 0, 12, 25, or 50 ml of excreta. After reaching prescribed excreta thresholds, females were dissected to determine egg load, hind tibia length, and head capsule width. Mature eggs were removed from the abdomen and dry weight of eggs and bodies (head, thorax, and abdomen) were obtained. Lipid content of eggs and bodies were determined using a quantitative colorimetric assay. Rates of body weight gain and body lipid gain were rapid with low levels of feeding (12 ml of excreta) but decelerated with additional feeding (>12 ml of excreta). In contrast, low levels of feeding (12 ml of excreta) resulted in little egg production, with rates of egg production accelerating with additional feeding (>12 ml of excreta). Accordingly, egg production was preceded by an increase in body dry weight and body lipid content. In agreement, probability that a female carried eggs increased with body lipid content in the 0-, 12-, and 25-ml feeding treatments. Across treatments, larger females carried more eggs than smaller females. Collectively, results suggest that variation in glassy-winged sharpshooter egg maturation rates partially may be explained by availability of lipid reserves at the start of a feeding bout and female size.


Asunto(s)
Hemípteros/fisiología , Animales , Tamaño Corporal , Conducta Alimentaria , Femenino , Hemípteros/crecimiento & desarrollo , Metabolismo de los Lípidos , Óvulo/crecimiento & desarrollo , Óvulo/fisiología
15.
Am J Respir Crit Care Med ; 188(12): 1434-41, 2013 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-24168209

RESUMEN

RATIONALE: Air trapping and airflow obstruction are being increasingly identified in infants with cystic fibrosis. These findings are commonly attributed to airway infection, inflammation, and mucus buildup. OBJECTIVES: To learn if air trapping and airflow obstruction are present before the onset of airway infection and inflammation in cystic fibrosis. METHODS: On the day they are born, piglets with cystic fibrosis lack airway infection and inflammation. Therefore, we used newborn wild-type piglets and piglets with cystic fibrosis to assess air trapping, airway size, and lung volume with inspiratory and expiratory X-ray computed tomography scans. Micro-computed tomography scanning was used to assess more distal airway sizes. Airway resistance was determined with a mechanical ventilator. Mean linear intercept and alveolar surface area were determined using stereologic methods. MEASUREMENTS AND MAIN RESULTS: On the day they were born, piglets with cystic fibrosis exhibited air trapping more frequently than wild-type piglets (75% vs. 12.5%, respectively). Moreover, newborn piglets with cystic fibrosis had increased airway resistance that was accompanied by luminal size reduction in the trachea, mainstem bronchi, and proximal airways. In contrast, mean linear intercept length, alveolar surface area, and lung volume were similar between both genotypes. CONCLUSIONS: The presence of air trapping, airflow obstruction, and airway size reduction in newborn piglets with cystic fibrosis before the onset of airway infection, inflammation, and mucus accumulation indicates that cystic fibrosis impacts airway development. Our findings suggest that early airflow obstruction and air trapping in infants with cystic fibrosis might, in part, be caused by congenital airway abnormalities.


Asunto(s)
Obstrucción de las Vías Aéreas/etiología , Fibrosis Quística/fisiopatología , Obstrucción de las Vías Aéreas/congénito , Obstrucción de las Vías Aéreas/diagnóstico por imagen , Obstrucción de las Vías Aéreas/patología , Resistencia de las Vías Respiratorias , Animales , Bronquios/patología , Bronquios/fisiopatología , Broncografía/métodos , Fibrosis Quística/diagnóstico por imagen , Fibrosis Quística/patología , Mediciones del Volumen Pulmonar , Tomografía Computarizada Multidetector , Alveolos Pulmonares/patología , Alveolos Pulmonares/fisiopatología , Porcinos , Tráquea/diagnóstico por imagen , Tráquea/patología , Tráquea/fisiopatología
16.
Plant Dis ; 98(9): 1186-1193, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30699616

RESUMEN

Olive (Olea europaea) trees exhibiting leaf scorch or branch dieback symptoms in California were surveyed for the xylem-limited, fastidious bacterium Xylella fastidiosa. Only approximately 17% of diseased trees tested positive for X. fastidiosa by polymerase chain reaction, and disease symptoms could not be attributed to X. fastidiosa infection of olive in greenhouse pathogenicity assays. Six strains of X. fastidiosa were isolated from olive in Southern California. Molecular assays identified strains recovered from olive as belonging to X. fastidiosa subsp. multiplex. Pathogenicity testing of olive strains on grapevine and almond confirmed that X. fastidiosa strains isolated from olive yield disease phenotypes on almond and grapevine typical of those expected for subsp. multiplex. Mechanical inoculation of X. fastidiosa olive strains to olive resulted in infection at low efficiency but infections remained asymptomatic and tended to be self-limiting. Vector transmission assays demonstrated that glassy-winged sharpshooter (Homalodisca vitripennis) could transmit strains of both subspp. multiplex and fastidiosa to olive at low efficiency. Insect trapping data indicated that two vectors of X. fastidiosa, glassy-winged sharpshooter and green sharpshooter (Draeculacephala minerva), were active in olive orchards. Collectively, the data indicate that X. fastidiosa did not cause olive leaf scorch or branch dieback but olive may contribute to the epidemiology of X. fastidiosa-elicited diseases in California. Olive may serve as an alternative, albeit suboptimal, host of X. fastidiosa. Olive also may be a refuge where sharpshooter vectors evade intensive areawide insecticide treatment of citrus, the primary control method used in California to limit glassy-winged sharpshooter populations and, indirectly, epidemics of Pierce's disease of grapevine.

17.
Biochim Biophys Acta Biomembr ; 1866(6): 184338, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38763269

RESUMEN

The molecular structures of the various intrinsic lipids in membranes regulate lipid-protein interactions. These different lipid structures with unique volumes produce different lipid molecular packing stresses/lateral stresses in lipid membranes. Most studies examining lipid packing effects have used phosphatidylcholine and phosphatidylethanolamine (PE), which are the main phospholipids of eukaryotic cell membranes. In contrast, Gram-negative or Gram-positive bacterial membranes are composed primarily of phosphatidylglycerol (PG) and PE, and the physical and thermodynamic properties of each acyl chain in PG at the molecular level remain unresolved. In this study, we used 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (POPG, 16:0-18:1 PG) and 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (PAPG, 16:0-20:4 PG) to prepare lipid bilayers (liposome) with the rod-type fluorescence probe DPH. We measured the lipid packing conditions by determining the rotational freedom of DPH in POPG or PAPG bilayers. Furthermore, we investigated the effect of different monoacyl chains on a K+ channel (KcsA) structure when embedded in POPG or PAPG membranes. The results revealed that differences in the number of double bonds and carbon chain length in the monoacyl chain at sn-2 affected the physicochemical properties of the membrane and the structure and orientation of KcsA.


Asunto(s)
Proteínas Bacterianas , Membrana Dobles de Lípidos , Fosfatidilgliceroles , Canales de Potasio , Membrana Dobles de Lípidos/química , Canales de Potasio/química , Canales de Potasio/metabolismo , Fosfatidilgliceroles/química , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Fosfatidiletanolaminas/química , Lípidos de la Membrana/química , Lípidos de la Membrana/metabolismo , Membrana Celular/química , Termodinámica , Liposomas/química , Fosfatidilcolinas/química
18.
Biochim Biophys Acta ; 1818(4): 951-6, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22236837

RESUMEN

Detailed investigations of membrane protein folding present a number of serious technical challenges. Most studies addressing this subject have emphasized aspects of protein amino acid sequence and structure. While it is generally accepted that the interplay between proteins and lipids plays an important role in membrane protein folding, the role(s) played by membrane lipids in this process have only recently been explored in any detail. This review is intended to summarize recent studies in which particular lipids or membrane physical properties have been shown to play a role in the folding of intact, functionally competent integral membrane proteins. This article is part of a Special Issue entitled: Protein Folding in Membranes.


Asunto(s)
Lípidos/química , Proteínas de la Membrana/química , Proteínas de la Membrana/metabolismo , Pliegue de Proteína , Estructura Secundaria de Proteína
19.
Int J Obes (Lond) ; 37(4): 552-8, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23419602

RESUMEN

OBJECTIVE: Short sleep duration is recognized as a significant risk factor in childhood obesity; however, the question as to how sleep contributes to the development of obesity remains largely unknown. The majority of pediatric studies have relied on sleep duration as the exclusive measure of sleep; this insular approach may be misleading given that sleep is a dynamic multidimensional construct beyond sleep duration, including sleep disturbances and patterns. Although these sleep dimensions partly overlap, it is necessary to determine their independent relation with obesity, which in turn, may inform a more comprehensive understanding of putative pathophysiological mechanisms linking sleep and obesity. The aim of the present study was to investigate whether sleep dimensions including sleep duration, disturbances, and patterns were individually associated with obesity, independent of multiple covariates. The second objective was to examine whether sleep disturbances and patterns were independently associated with obesity, after adjusting for sleep duration. METHODS: Participants included 240 healthy children and adolescents (Mage=12.60, s.d.=1.98; 45.8% females). Anthropometric measures included measured waist and hip circumference, body mass index Z-score, and percent body fat. Subjective sleep measures included sleep duration, sleep disturbances, sleep quality, and sleep patterns from youth- and parental report. RESULTS: Youth with larger adiposity and body composition measures reported poorer sleep quality (ß avg=-0.14, P<0.01), more sleep disturbances (ß avg=0.13, P<0.05), and showed a delayed sleep phase pattern (ß avg=0.15, P<0.05), independent of age, sex, pubertal status, physical activity, screen time, socioeconomic status, and sleep duration. Shorter sleep duration was significantly associated with obesity; however, this link was attenuated after adjustment of covariates. CONCLUSIONS: The results suggest that sleep measures beyond duration may more precisely capture influences that drive the negative association between sleep and obesity, and thus, yield more robust associations. As such, future studies are needed to better understand how distinct sleep dimensions confer risk for childhood obesity.


Asunto(s)
Ritmo Circadiano , Obesidad/epidemiología , Sueño , Adolescente , Factores de Edad , Distribución de la Grasa Corporal , Índice de Masa Corporal , Canadá/epidemiología , Niño , Estudios Transversales , Ingestión de Alimentos , Conducta Alimentaria , Femenino , Humanos , Estudios Longitudinales , Masculino , Actividad Motora , Obesidad/complicaciones , Pubertad , Factores de Riesgo , Factores de Tiempo , Circunferencia de la Cintura
20.
J Neurooncol ; 114(1): 149-54, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23780645

RESUMEN

Neutrophil-lymphocyte ratio (NLR) is a marker of systemic inflammatory response and its elevation has recently been shown to be a poor prognostic factor in many malignancies including colon, prostate and bladder cancer. The primary aim of this study was to assess the prognostic impact of NLR in a clinically annotated cohort of patients with glioblastoma multiforme (GBM). We hypothesised that elevated NLR would be associated with worse prognosis. Between 2004 and 2009, 137 patients had surgery for GBM and were assessed for consideration of adjuvant therapy at our institution. Of these, 84 patients with an evaluable pre-corticosteroid full blood count result were identified and included in the final analysis. Median overall survival was 9.3 months (range 0.7-82.1). On univariate analysis, age >65 years, gender, ECOG performance status ≥2, frontal tumour, extent of surgical resection, completion of adjuvant chemoradiation protocol and NLR > 4 were significantly correlated with overall survival. Patients with NLR > 4, had a worse median overall survival at 7.5 months versus 11.2 months in patients with NLR ≤ 4 (hazard ratio 1.6, 95 % CI 1.00-2.52, p = 0.048). On multivariate analysis NLR > 4 remained an independent prognostic indicator for poor outcome. These data are an important reminder of the potential relevance of host immunity in GBM. In our cohort, NLR > 4 conferred a worse prognosis independent of other well established prognostic factors. If validated in other cohorts NLR may prove to be a useful addition in predicting prognosis in GBM patients. The demonstration that host immunity plays a role in GBM biology suggests that investigation of emerging therapies which modulate host immune response are warranted in this disease.


Asunto(s)
Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/patología , Glioblastoma/mortalidad , Glioblastoma/patología , Linfocitos/patología , Neutrófilos/patología , Adolescente , Adulto , Factores de Edad , Anciano , Recuento de Células Sanguíneas , Supervivencia sin Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Estadísticas no Paramétricas , Adulto Joven
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