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1.
Proc Natl Acad Sci U S A ; 120(46): e2302814120, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-37934821

RESUMEN

Male crickets attract females by producing calls with their forewings. Louder calls travel further and are more effective at attracting mates. However, crickets are much smaller than the wavelength of their call, and this limits their power output. A small group called tree crickets make acoustic tools called baffles which reduce acoustic short-circuiting, a source of dipole inefficiency. Here, we ask why baffling is uncommon among crickets. We hypothesize that baffling may be rare because like other tools they offer insufficient advantage for most species. To test this, we modelled the calling efficiencies of crickets within the full space of possible natural wing sizes and call frequencies, in multiple acoustic environments. We then generated efficiency landscapes, within which we plotted 112 cricket species across 7 phylogenetic clades. We found that all sampled crickets, in all conditions, could gain efficiency from tool use. Surprisingly, we also found that calling from the ground significantly increased efficiency, with or without a baffle, by as much as an order of magnitude. We found that the ground provides some reduction of acoustic short-circuiting but also halves the air volume within which sound is radiated. It simultaneously reflects sound upwards, allowing recapture of a significant amount of acoustic energy through constructive interference. Thus, using the ground as a reflective baffle is an effective strategy for increasing calling efficiency. Indeed, theory suggests that this increase in efficiency is accessible not just to crickets but to all acoustically communicating animals whether they are dipole or monopole sound sources.


Asunto(s)
Críquet , Gryllidae , Animales , Femenino , Filogenia , Acústica , Sonido , Alas de Animales , Vocalización Animal , Estimulación Acústica
2.
Transfusion ; 55 Suppl 2: S90-4, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26174904

RESUMEN

BACKGROUND: Kawasaki disease (KD) is an idiopathic, multisystem disorder characterized by vasculitis of arteries, veins, and capillaries, affecting pediatric patients, and is the leading cause of acquired heart disease in childhood. The mainstays of therapy for KD are high-dose intravenous immunoglobulin (IVIG) and aspirin, which are thought to prevent or modify the most serious cardiac sequelae. A well-documented complication of high-dose IVIG infusion in adults is hemolytic anemia due to passive transfer of anti-A and anti-B. Risk factors for hemolysis in another case series included patient blood group (group A, B, or AB), a high cumulative dose of IVIG, and concomitant inflammation documented by one or more markers like ferritin, fibrinogen, erythrocyte sedimentation rate, or C-reactive protein. STUDY DESIGN AND METHODS: A 3-year retrospective case review of patients previously recognized with apparent IVIG-related hemolytic anemia identified by standard blood bank testing was performed at a tertiary care pediatric hospital. RESULTS: Five patients were identified with severe anemia each requiring RBC transfusion for anemia. All five patients demonstrated a positive direct antiglobulin testing. Four of five patients had anti-A, anti-B, and/or anti-A1 with elution assays. All patients had signs of extravascular hemolysis with reticulocytosis, spherocytosis, and other hemolysis markers. One child died. CONCLUSION: Our cases represent dose-dependent hemolysis caused by IVIG in association with severe anemia requiring transfusion with an average yearly incidence rate of 0.36%. Hemolysis is an underrecognized complication of IVIG administration. KD patients are at greater risk for anemia because of their lower baseline hemoglobin concentration, underlying acute inflammation, and oxygen requirements during acute illness.


Asunto(s)
Anemia , Transfusión de Eritrocitos , Hemólisis/efectos de los fármacos , Inmunoglobulinas Intravenosas/efectos adversos , Factores Inmunológicos/efectos adversos , Síndrome Mucocutáneo Linfonodular/tratamiento farmacológico , Adolescente , Anemia/inducido químicamente , Anemia/terapia , Niño , Preescolar , Femenino , Humanos , Inmunoglobulinas Intravenosas/administración & dosificación , Factores Inmunológicos/administración & dosificación , Lactante , Masculino , Estudios Retrospectivos
3.
Avian Dis ; 59(1): 165-70, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26292553

RESUMEN

Electron-beam (eBeam) irradiation technology has a variety of applications in modern society. The underlying hypothesis was that eBeam-inactivated Salmonella enterica serovar Enteritidis (SE) cells can serve as a vaccine to control SE colonization and shedding in poultry birds. An eBeam dose of 2.5 kGy (kilograys) was used to inactivate a high-titer (10(8) colony-forming units [CFU]) preparation of SE cells. Microscopic studies revealed that the irradiation did not damage the bacterial cell membranes. The vaccine efficacy was evaluated by administering the eBeam-killed SE cells intramuscularly (1 x 10(6) CFU/bird) into 50-wk-old single comb white leghorn hens. On day 14 postvaccination, the hens were challenged orally with live SE cells (1 x 10(9) CFU) and SE colonization of liver, spleen, ceca, and ovaries determined on day 23. Blood samples were collected on days 0, 14, and 23 postvaccination and the sera were analyzed to quantify SE-specific IgG titers. The vaccinated chickens exhibited significantly (P < 0.0001) higher SE-specific IgG antibody responses and reduced SE ceca colonization (1.46 ± 0.39 logi10 CFU/g) compared to nonvaccinated birds (5.32 ± 0.32 log10 CFU/g). They also exhibited significantly lower SE colonization of the ovaries (1/30), spleen (3/30), liver (4/30), and ceca (7/30) compared to nonvaccinated birds. These results provide empirical evidence that eBeam-based SE vaccines are immunogenic and are capable of protecting chickens against SE colonization. The advantages of eBeam-based vaccine technology are that it is nonthermal, avoids the use of formalin, and can be used to generate inactivated vaccines rapidly to address strain-specific infections in farms or flocks.


Asunto(s)
Vacunas Bacterianas/inmunología , Pollos , Muda , Salmonelosis Animal/prevención & control , Salmonella enteritidis/efectos de la radiación , Animales , Anticuerpos Antibacterianos/sangre , Femenino , Inmunoglobulina G/sangre , Vacunas de Productos Inactivados
4.
PLoS One ; 17(12): e0268730, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36454958

RESUMEN

Feline upper respiratory tract disease (FURTD), often caused by infections etiologies, is a multifactorial syndrome affecting feline populations worldwide. Because of its highly transmissible nature, infectious FURTD is most prevalent anywhere cats are housed in groups such as animal shelters, and is associated with negative consequences such as decreasing adoption rates, intensifying care costs, and increasing euthanasia rates. Understanding the etiology and pathophysiology of FURTD is thus essential to best mitigate the negative consequences of this disease. Clinical signs of FURTD include acute respiratory disease, with a small fraction of cats developing chronic sequelae. It is thought that nasal mucosal microbiome changes play an active role in the development of acute clinical signs, but it remains unknown if the microbiome may play a role in the development and progression of chronic clinical disease. To address the knowledge gap surrounding how microbiomes link to chronic FURTD, we asked if microbial community structure of upper respiratory and gut microbiomes differed between cats with chronic FURTD signs and clinically normal cats. We selected 8 households with at least one cat exhibiting chronic clinical FURTD, and simultaneously collected samples from cohabitating clinically normal cats. Microbial community structure was assessed via 16S rDNA sequencing of both gut and nasal microbiome communities. Using a previously described ecophylogenetic method, we identified 136 and 89 microbial features within gut and nasal microbiomes respectively that significantly associated with presence of active FURTD clinical signs in cats with a history of chronic signs. Overall, we find that nasal and gut microbial community members associate with the presence of chronic clinical course, but more research is needed to confirm our observations.


Asunto(s)
Enfermedad Injerto contra Huésped , Microbiota , Trastornos Respiratorios , Gatos , Animales , Estudios de Cohortes , Microbiota/genética , Frecuencia Respiratoria , Mucosa Nasal
5.
Res Vet Sci ; 123: 118-123, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30641470

RESUMEN

The majority of cattle found to have violative liver residues of flunixin (FNX) in the United States are dairy cows. It has been hypothesized that illness of cows decreases the rate of FNX metabolism, resulting in violative residues at slaughter. Another contributing factor might be an age-related decrease in FNX metabolism, as dairy cull cows are typically older at slaughter than cattle raised for beef, rather than milk production. In order to investigate this possibility, subcellular fractions were prepared from liver slices from steers (n = 6) and heifers (n = 5) <30 months of age, and cows (n = 8) >48 mos of age. Cytochrome P450 (P450), NADPH-P450 reductase and glucose-6-phosphate dehydrogenase (G6PDH) activity and rate of 5-hydroxy FNX (5-OH FNX) formation were measured in liver homogenate, cytosolic, microsomal, and S9 fractions. Cows had lower concentrations of P450, NADPH-P450 reductase activity, and 5-OH FNX formation (P ≤ 0. 02), supporting the theory that advanced age may contribute to the higher incidence of violative FNX residues in dairy cows.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacocinética , Bovinos/metabolismo , Clonixina/análogos & derivados , Hígado/metabolismo , Animales , Antiinflamatorios no Esteroideos/metabolismo , Clonixina/metabolismo , Clonixina/farmacocinética , Sistema Enzimático del Citocromo P-450/metabolismo , Femenino , Masculino , Técnicas de Cultivo de Tejidos
6.
BMC Biol ; 5: 30, 2007 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-17651495

RESUMEN

BACKGROUND: Understanding the role of seascape in shaping genetic and demographic population structure is highly challenging for marine pelagic species such as cetaceans for which there is generally little evidence of what could effectively restrict their dispersal. In the present work, we applied a combination of recent individual-based landscape genetic approaches to investigate the population genetic structure of a highly mobile extensive range cetacean, the harbour porpoise in the eastern North Atlantic, with regards to oceanographic characteristics that could constrain its dispersal. RESULTS: Analyses of 10 microsatellite loci for 752 individuals revealed that most of the sampled range in the eastern North Atlantic behaves as a 'continuous' population that widely extends over thousands of kilometres with significant isolation by distance (IBD). However, strong barriers to gene flow were detected in the south-eastern part of the range. These barriers coincided with profound changes in environmental characteristics and isolated, on a relatively small scale, porpoises from Iberian waters and on a larger scale porpoises from the Black Sea. CONCLUSION: The presence of these barriers to gene flow that coincide with profound changes in oceanographic features, together with the spatial variation in IBD strength, provide for the first time strong evidence that physical processes have a major impact on the demographic and genetic structure of a cetacean. This genetic pattern further suggests habitat-related fragmentation of the porpoise range that is likely to intensify with predicted surface ocean warming.


Asunto(s)
Oceanografía/tendencias , Phocoena/genética , Agua de Mar , Migración Animal/fisiología , Animales , Océano Atlántico , Cetáceos , Análisis por Conglomerados , Variación Genética/genética , Oceanografía/métodos , Océanos y Mares
7.
Fam Cancer ; 11(3): 509-18, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22773173

RESUMEN

Approximately 25 % of mismatch repair (MMR) variants are exonic nucleotide substitutions. Some result in the substitution of one amino acid for another in the protein sequence, so-called missense variants, while others are silent. The interpretation of the effect of missense and silent variants as deleterious or neutral is challenging. Pre-symptomatic testing for clinical use is not recommended for relatives of individuals with variants classified as 'of uncertain significance'. These relatives, including non-carriers, are considered at high-risk as long as the contribution of the variant to disease causation cannot be determined. This results in continuing anxiety, and the application of potentially unnecessary screening and prophylactic interventions. We encountered a large Irish Lynch syndrome kindred that carries the c.544A>G (p.Arg182Gly) alteration in the MLH1 gene and we undertook to study the variant. The clinical significance of the variant remains unresolved in the literature. Data are presented on cancer incidence within five kindreds with the same germline missense variant in the MLH1 MMR gene. Extensive testing of relevant family members in one kindred, a review of the literature, review of online MMR mutation databases and use of in silico phenotype prediction tools were undertaken to study the significance of this variant. Clinical, histological, immunohistochemical and molecular evidence from these families and other independent clinical and scientific evidence indicates that the MLH1 p.Arg182Gly (c.544A>G) change causes Lynch syndrome and supports reclassification of the variant as pathogenic.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Mutación , Proteínas Nucleares/genética , Adulto , Anciano , Femenino , Pruebas Genéticas , Humanos , Masculino , Persona de Mediana Edad , Homólogo 1 de la Proteína MutL , Linaje
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