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1.
Nature ; 562(7725): 82-85, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30283106

RESUMEN

SS 433 is a binary system containing a supergiant star that is overflowing its Roche lobe with matter accreting onto a compact object (either a black hole or neutron star)1-3. Two jets of ionized matter with a bulk velocity of approximately 0.26c (where c is the speed of light in vacuum) extend from the binary, perpendicular to the line of sight, and terminate inside W50, a supernova remnant that is being distorted by the jets2,4-8. SS 433 differs from other microquasars (small-scale versions of quasars that are present within our own Galaxy) in that the accretion is believed to be super-Eddington9-11, and the luminosity of the system is about 1040 ergs per second2,9,12,13. The lobes of W50 in which the jets terminate, about 40 parsecs from the central source, are expected to accelerate charged particles, and indeed radio and X-ray emission consistent with electron synchrotron emission in a magnetic field have been observed14-16. At higher energies (greater than 100 gigaelectronvolts), the particle fluxes of γ-rays from X-ray hotspots around SS 433 have been reported as flux upper limits6,17-20. In this energy regime, it has been unclear whether the emission is dominated by electrons that are interacting with photons from the cosmic microwave background through inverse-Compton scattering or by protons that are interacting with the ambient gas. Here we report teraelectronvolt γ-ray observations of the SS 433/W50 system that spatially resolve the lobes. The teraelectronvolt emission is localized to structures in the lobes, far from the centre of the system where the jets are formed. We have measured photon energies of at least 25 teraelectronvolts, and these are certainly not Doppler-boosted, because of the viewing geometry. We conclude that the emission-from radio to teraelectronvolt energies-is consistent with a single population of electrons with energies extending to at least hundreds of teraelectronvolts in a magnetic field of about 16 microgauss.

3.
Antimicrob Agents Chemother ; 67(3): e0142622, 2023 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-36744891

RESUMEN

Moxifloxacin is included in some treatment regimens for drug-sensitive tuberculosis (TB) and multidrug-resistant TB (MDR-TB). Aiming to optimize dosing, we described moxifloxacin pharmacokinetic and MIC distribution in participants with MDR-TB. Participants enrolled at two TB hospitals in South Africa underwent intensive pharmacokinetic sampling approximately 1 to 6 weeks after treatment initiation. Plasma drug concentrations and clinical data were analyzed using nonlinear mixed-effects modeling with simulations to evaluate doses for different scenarios. We enrolled 131 participants (54 females), with median age of 35.7 (interquartile range, 28.5 to 43.5) years, median weight of 47 (42.0 to 54.0) kg, and median fat-free mass of 40.1 (32.3 to 44.7) kg; 79 were HIV positive, 29 of whom were on efavirenz-based antiretroviral therapy. Moxifloxacin pharmacokinetics were described with a 2-compartment model, transit absorption, and elimination via a liver compartment. We included allometry based on fat-free mass to estimate disposition parameters. We estimated an oral clearance for a typical patient to be 17.6 L/h. Participants treated with efavirenz had increased clearance, resulting in a 44% reduction in moxifloxacin exposure. Simulations predicted that, even at a median MIC of 0.25 (0.06 to 16) mg/L, the standard daily dose of 400 mg has a low probability of attaining the ratio of the area under the unbound concentration-time curve from 0 to 24 h to the MIC (fAUC0-24)/MIC target of >53, particularly in heavier participants. The high-dose WHO regimen (600 to 800 mg) yielded higher, more balanced exposures across the weight ranges, with better target attainment. When coadministered with efavirenz, moxifloxacin doses of up to 1,000 mg are needed to match these exposures. The safety of higher moxifloxacin doses in clinical settings should be confirmed.


Asunto(s)
Antituberculosos , Tuberculosis Resistente a Múltiples Medicamentos , Femenino , Humanos , Adulto , Moxifloxacino/uso terapéutico , Antituberculosos/farmacocinética , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Alquinos/uso terapéutico
4.
Phys Rev Lett ; 131(5): 051201, 2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37595214

RESUMEN

We report the first detection of a TeV γ-ray flux from the solar disk (6.3σ), based on 6.1 years of data from the High Altitude Water Cherenkov (HAWC) observatory. The 0.5-2.6 TeV spectrum is well fit by a power law, dN/dE=A(E/1 TeV)^{-γ}, with A=(1.6±0.3)×10^{-12} TeV^{-1} cm^{-2} s^{-1} and γ=3.62±0.14. The flux shows a strong indication of anticorrelation with solar activity. These results extend the bright, hard GeV emission from the disk observed with Fermi-LAT, seemingly due to hadronic Galactic cosmic rays showering on nuclei in the solar atmosphere. However, current theoretical models are unable to explain the details of how solar magnetic fields shape these interactions. HAWC's TeV detection thus deepens the mysteries of the solar-disk emission.

5.
J Microsc ; 288(3): 155-168, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35348205

RESUMEN

Insight into the nucleation, growth and phase transformations of calcium sulphate could improve the performance of construction materials, reduce scaling in industrial processes and aid understanding of its formation in the natural environment. Recent studies have suggested that the calcium sulphate pseudo polymorph, gypsum (CaSO4 ·2H2 O) can form in aqueous solution via a bassanite (CaSO4 ·0.5H2 O) intermediate. Some in situ experimental work has also suggested that the transformation of bassanite to gypsum can occur through an oriented assembly mechanism. In this work, we have exploited liquid cell transmission electron microscopy (LCTEM) to study the transformation of bassanite to gypsum in an undersaturated aqueous solution of calcium sulphate. This was benchmarked against cryogenic TEM (cryo-TEM) studies to validate internally the data obtained from the two microscopy techniques. When coupled with Raman spectroscopy, the real-time data generated by LCTEM, and structural data obtained from cryo-TEM show that bassanite can transform to gypsum via more than one pathway, the predominant one being dissolution/reprecipitation. Comparisons between LCTEM and cryo-TEM also show that the transformation is slower within the confined region of the liquid cell as compared to a bulk solution. This work highlights the important role of a correlated microscopy approach for the study of dynamic processes such as crystallisation from solution if we are to extract true mechanistic understanding.


Asunto(s)
Sulfato de Calcio , Sulfato de Calcio/química , Microscopía Electrónica de Transmisión , Cristalización
6.
Invest New Drugs ; 39(3): 785-795, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33389388

RESUMEN

Background Ulixertinib is the first-in-class ERK1/2 kinase inhibitor with encouraging clinical activity in BRAF- and NRAS-mutant cancers. Dermatologic adverse events (dAEs) are common with ulixertinib, so management guidelines like those established for epidermal growth factor receptor inhibitor (EGFRi)-associated dAEs are needed. Patients and Methods This was an open-label, multicenter, phase I dose escalation and expansion trial of ulixertinib evaluating data from 135 patients with advanced malignancies enrolled between March 2013 and July 2017. Histopathological features, management, and dAEs in 34 patients are also reported. Twice daily oral ulixertinib was administered at 10 to 900 mg in the dose escalation cohort (n = 27) and at 600 mg in 21-day cycles in the expansion cohort (n = 108). Results The incidence of ulixertinib-induced dAEs and combined rash were 79% (107/135) and 76% (102/135). The most common dAEs included acneiform rash (45/135, 33%), maculopapular rash (36/135, 27%), and pruritus (34/135, 25%). Grade 3 dAEs were observed in 19% (25/135) of patients; no grade 4 or 5 dAEs were seen. The presence of at least 1 dAE was associated with stable disease (SD) or partial response (PR) (OR = 3.64, 95% CI 1.52-8.72; P = .003). Acneiform rash was associated with a PR (OR = 10.19, 95% CI 2.67-38.91; P < .001). Conclusion The clinical spectrum of ulixertinib-induced dAEs was similar to EGFR and MEK inhibitors; dAEs may serve as a surrogate marker of tumor response. We propose treatment algorithms for common ERK inhibitor-induced dAEs to maintain patients' quality of life and dose intensity for maximal clinical benefit. Clinical Trial Registration: NCT01781429.


Asunto(s)
Aminopiridinas/efectos adversos , Analgésicos/uso terapéutico , Antibacterianos/uso terapéutico , Antineoplásicos/efectos adversos , Erupciones por Medicamentos/tratamiento farmacológico , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/efectos adversos , Pirroles/efectos adversos , Esteroides/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Erupciones por Medicamentos/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Piel/efectos de los fármacos , Piel/patología , Adulto Joven
7.
Ann Oncol ; 31(9): 1207-1215, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32422171

RESUMEN

BACKGROUND: The tropomyosin receptor kinase (TRK) pathway controls appetite, balance, and pain sensitivity. While these functions are reflected in the on-target adverse events (AEs) observed with TRK inhibition, these AEs remain under-recognized, and pain upon drug withdrawal has not previously been reported. As TRK inhibitors are approved by multiple regulatory agencies for TRK or ROS1 fusion-positive cancers, characterizing these AEs and corresponding management strategies is crucial. PATIENTS AND METHODS: Patients with advanced or unresectable solid tumors treated with a TRK inhibitor were retrospectively identified in a search of clinical databases. Among these patients, the frequency, severity, duration, and management outcomes of AEs including weight gain, dizziness or ataxia, and withdrawal pain were characterized. RESULTS: Ninety-six patients with 15 unique cancer histologies treated with a TRK inhibitor were identified. Weight gain was observed in 53% [95% confidence interval (CI), 43%-62%] of patients and increased with time on TRK inhibition. Pharmacologic intervention, most commonly with glucagon-like peptide 1 analogs or metformin, appeared to result in stabilization or loss of weight. Dizziness, with or without ataxia, was observed in 41% (95% CI, 31%-51%) of patients with a median time to onset of 2 weeks (range, 3 days to 16 months). TRK inhibitor dose reduction was the most effective intervention for dizziness. Pain upon temporary or permanent TRK inhibitor discontinuation was observed in 35% (95% CI, 24%-46%) of patients; this was more common with longer TRK inhibitor use. TRK inhibitor reinitiation was the most effective intervention for withdrawal pain. CONCLUSIONS: TRK inhibition-related AEs including weight gain, dizziness, and withdrawal pain occur in a substantial proportion of patients receiving TRK inhibitors. This safety profile is unique relative to other anticancer therapies and warrants careful monitoring. These on-target toxicities are manageable with pharmacologic intervention and dose modification.


Asunto(s)
Proteínas Tirosina Quinasas , Receptor trkA , Humanos , Proteínas Proto-Oncogénicas , Pirazoles , Pirimidinas , Estudios Retrospectivos
8.
Phys Rev Lett ; 124(13): 131101, 2020 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-32302173

RESUMEN

Because of the high energies and long distances to the sources, astrophysical observations provide a unique opportunity to test possible signatures of Lorentz invariance violation (LIV). Superluminal LIV enables the decay of photons at high energy. The high altitude water Cherenkov (HAWC) observatory is among the most sensitive gamma-ray instruments currently operating above 10 TeV. HAWC finds evidence of 100 TeV photon emission from at least four astrophysical sources. These observations exclude, for the strongest of the limits set, the LIV energy scale to 2.2×10^{31} eV, over 1800 times the Planck energy and an improvement of 1 to 2 orders of magnitude over previous limits.

9.
Phys Rev Lett ; 124(2): 021102, 2020 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-32004015

RESUMEN

We present the first catalog of gamma-ray sources emitting above 56 and 100 TeV with data from the High Altitude Water Cherenkov Observatory, a wide field-of-view observatory capable of detecting gamma rays up to a few hundred TeV. Nine sources are observed above 56 TeV, all of which are likely galactic in origin. Three sources continue emitting past 100 TeV, making this the highest-energy gamma-ray source catalog to date. We report the integral flux of each of these objects. We also report spectra for three highest-energy sources and discuss the possibility that they are PeVatrons.

10.
Clin Radiol ; 75(5): 366-374, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32000985

RESUMEN

AIM: To explore the relationship of embolic particle size used in prostate artery embolisation (PAE) to patient outcomes. MATERIALS AND METHODS: A systematic review of PubMed, EMBASE, and the Cochrane database was undertaken to identify all existing studies using PAE for benign prostatic hyperplasia (BPH). Inclusion criteria included prospective studies reporting baseline and 12-month International Prostate Symptom Score (IPSS) and particle size. Exclusion criteria were overlapping studies, commentaries, abstracts, and letters. Data extraction from eligible studies included the size of embolic particle, particle material, and baseline and 12-month values for the following patient outcomes: IPSS, IPSS quality of life, urinary flow rate (Q-max), prostate volume, prostate specific antigen, and post-void residual volume. A meta-regression analysis was then undertaken to examine the relationship of particle size to patient outcome measures. RESULTS: Six studies with a total of 687 patients were identified. Meta-regression analysis demonstrated particle size as a statistically significant (p<0.001) moderator of 12-month IPSS change following PAE. No statistically significant relationships were identified with other patient outcome measures. CONCLUSION: Smaller embolic particle size is associated with a greater reduction in IPSS following PAE.


Asunto(s)
Embolización Terapéutica/métodos , Próstata/irrigación sanguínea , Hiperplasia Prostática/terapia , Resinas Acrílicas/administración & dosificación , Gelatina/administración & dosificación , Humanos , Masculino , Tamaño de la Partícula , Alcohol Polivinílico/administración & dosificación , Radiografía Intervencional
11.
J Physiol ; 596(23): 5925-5945, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29235113

RESUMEN

KEY POINTS: Fetal growth restriction increases the risk of fetal and neonatal mortality and morbidity, and contributes to increased risk of chronic disease later in life. Intra-amniotic insulin-like growth factor-1 (IGF1) treatment of the growth-restricted ovine fetus improves fetal growth, but postnatal effects are unknown. Here we report that intra-amniotic IGF1 treatment of the growth-restricted ovine fetus alters size at birth and mechanisms of early postnatal growth in a sex-specific manner. We also show that maternal plasma C-type natriuretic peptide (CNP) products are related to fetal oxygenation and size at birth, and hence may be useful for non-invasive monitoring of fetal growth restriction. Intrauterine IGF1 treatment in late gestation is a potentially clinically relevant intervention that may ameliorate the postnatal complications of fetal growth restriction. ABSTRACT: Placental insufficiency-mediated fetal growth restriction (FGR) is associated with altered postnatal growth and metabolism, which are, in turn, associated with increased risk of adult disease. Intra-amniotic insulin-like growth factor-1 (IGF1) treatment of ovine FGR increases growth rate in late gestation, but the effects on postnatal growth and metabolism are unknown. We investigated the effects of intra-amniotic IGF1 administration to ovine fetuses with uteroplacental embolisation-induced FGR on phenotypical and physiological characteristics in the 2  weeks after birth. We measured early postnatal growth velocity, amino-terminal propeptide of C-type natriuretic peptide (NTproCNP), body composition, tissue-specific mRNA expression, and milk intake in singleton lambs treated weekly with 360 µg intra-amniotic IGF1 (FGRI; n = 13 females, 19 males) or saline (FGRS; n = 18 females, 12 males) during gestation, and in controls (CON; n = 15 females, 22 males). There was a strong positive correlation between maternal NTproCNP and fetal oxygenation, and size at birth in FGR lambs. FGR lambs were ∼20% lighter at birth and demonstrated accelerated postnatal growth velocity. IGF1 treatment did not alter perinatal mortality, partially abrogated the reduction in newborn size in females, but not males, and reduced accelerated growth in both sexes. IGF1-mediated upregulation of somatotrophic genes in males during the early postnatal period could suggest that treatment effects are associated with delayed axis maturation, whilst treatment outcomes in females may rely on the reprogramming of nutrient-dependent mechanisms of growth. These data suggest that the growth-restricted fetus is responsive to intra-amniotic intervention with IGF1, and that sex-specific somatotrophic effects persist in the early postnatal period.


Asunto(s)
Desarrollo Fetal/efectos de los fármacos , Retardo del Crecimiento Fetal/tratamiento farmacológico , Factor I del Crecimiento Similar a la Insulina/administración & dosificación , Líquido Amniótico , Animales , Animales Recién Nacidos , Femenino , Retardo del Crecimiento Fetal/genética , Feto/efectos de los fármacos , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Masculino , Péptido Natriurético Tipo-C/sangre , Embarazo , Ovinos
12.
Ann Oncol ; 29(6): 1402-1408, 2018 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-29659672

RESUMEN

Background: Arginine depletion is a putative target in hepatocellular carcinoma (HCC). HCC often lacks argininosuccinate synthetase, a citrulline to arginine-repleting enzyme. ADI-PEG 20 is a cloned arginine degrading enzyme-arginine deiminase-conjugated with polyethylene glycol. The goal of this study was to evaluate this agent as a potential novel therapeutic for HCC after first line systemic therapy. Methods and patients: Patients with histologically proven advanced HCC and Child-Pugh up to B7 with prior systemic therapy, were randomized 2 : 1 to ADI-PEG 20 18 mg/m2 versus placebo intramuscular injection weekly. The primary end point was overall survival (OS), with 93% power to detect a 4-5.6 months increase in median OS (one-sided α = 0.025). Secondary end points included progression-free survival, safety, and arginine correlatives. Results: A total of 635 patients were enrolled: median age 61, 82% male, 60% Asian, 52% hepatitis B, 26% hepatitis C, 76% stage IV, 91% Child-Pugh A, 70% progressed on sorafenib and 16% were intolerant. Median OS was 7.8 months for ADI-PEG 20 versus 7.4 for placebo (P = 0.88, HR = 1.02) and median progression-free survival 2.6 months versus 2.6 (P = 0.07, HR = 1.17). Grade 3 fatigue and decreased appetite occurred in <5% of patients. Two patients on ADI-PEG 20 had ≥grade 3 anaphylactic reaction. Death rate within 30 days of end of treatment was 15.2% on ADI-PEG 20 versus 10.4% on placebo, none related to therapy. Post hoc analyses of arginine assessment at 4, 8, 12 and 16 weeks, demonstrated a trend of improved OS for those with more prolonged arginine depletion. Conclusion: ADI-PEG 20 monotherapy did not demonstrate an OS benefit in second line setting for HCC. It was well tolerated. Strategies to enhance prolonged arginine depletion and synergize the effect of ADI-PEG 20 are underway. Clinical Trial number: www.clinicaltrials.gov (NCT 01287585).


Asunto(s)
Carcinoma Hepatocelular/terapia , Hidrolasas/uso terapéutico , Neoplasias Hepáticas/terapia , Cuidados Paliativos , Polietilenglicoles/uso terapéutico , Carcinoma Hepatocelular/patología , Terapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Pronóstico , Tasa de Supervivencia
13.
Anim Genet ; 48(2): 228-232, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27943331

RESUMEN

Porcine epidemic diarrhea virus (PEDV) belongs to the Coronaviridae family and causes malabsorptive watery diarrhea, vomiting, dehydration and imbalanced blood electrolytes in pigs. Since the 1970s, PED outbreaks have become a source of problems in pig producing countries all over the world, causing large economic losses for pig producers. Although the infection in adults is not fatal, in naïve suckling piglets mortality is close to 100%. In this study, we investigated genome-wide differences between dead and recovered suckling piglets from commercial farms after PED outbreaks. Samples from 262 animals (156 dead and 106 recovered) belonging to several commercial lines were collected from five different farms in three different countries (USA, Canada and Germany) and genotyped with the porcine 80K SNP chip. Mean Fst value was calculated in 1-Mb non-overlapping windows between dead and recovered individuals, and the results were normalized to find differences within the comparison. Seven windows with high divergence between dead and recovered were detected-five on chromosome 2, one on chromosome 4 and one on chromosome 15-in total encompassing 152 genes. Several of these genes are either under- or overexpressed in many virus infections, including Coronaviridae (such as SARS-CoV). A total of 32 genes are included in one or more Gene Ontology terms that can be related to PED development, such as Golgi apparatus, as well as mechanisms generally linked to resilience or diarrhea development (cell proliferation, ion transport, ATPase activity). Taken together this information provides a first genomic picture of PEDV resilience in suckling piglets.


Asunto(s)
Infecciones por Coronavirus/veterinaria , Virus de la Diarrea Epidémica Porcina/fisiología , Enfermedades de los Porcinos/genética , Enfermedades de los Porcinos/inmunología , Animales , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/genética , Infecciones por Coronavirus/inmunología , Brotes de Enfermedades , Sus scrofa , Porcinos , Enfermedades de los Porcinos/epidemiología
14.
Vet Pathol ; 52(3): 489-96, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25051955

RESUMEN

Porcine periweaning failure-to-thrive syndrome (PFTS) is a clinical syndrome characterized by anorexia and progressive debilitation of newly weaned pigs. The objectives of the current case-control study were to describe the histopathologic features of PFTS in North America and test for selected pathogens in case and control pigs on 8 farms allegedly fulfilling the clinical definition of PFTS. Based on observations during farm visits, 5 farms fully met the case definition (PFTS farms), whereas 3 farms only partially fulfilled the definition (NON-PFTS farms). Necropsy and histopathologic examination were performed on case (n = 8 or 9) and control (n = 4) pigs from each farm. Superficial gastritis, which was mainly localized in the fundus and characterized by attenuation of superficial foveolar cells, was significantly more frequent in case pigs from PFTS farms compared with all the other pigs (odds ratio [OR], 16.7). The same was found for thymic atrophy (OR, 30.1) and small intestinal (SI) villous atrophy in the duodenum (OR, 28.7), jejunum (OR, 67.4), and ileum (OR, 56.3). All pigs with PFTS had at least 2 of these 3 lesions: gastritis, thymic atrophy, and SI villous atrophy. PFTS was not associated with any relevant porcine pathogen tested. We propose the diagnosis of PFTS be based on the fulfillment of the clinical case definition, the presence of the above lesions, and exclusion of other common swine diseases and pathogens. However, PFTS can be ruled out if debilitated pigs do not have at least 2 of the above 3 lesions.


Asunto(s)
Insuficiencia de Crecimiento/veterinaria , Enfermedades de los Porcinos/patología , Animales , Animales Recién Nacidos/crecimiento & desarrollo , Anorexia/patología , Anorexia/veterinaria , Atrofia/patología , Atrofia/veterinaria , Estudios de Casos y Controles , Insuficiencia de Crecimiento/diagnóstico , Insuficiencia de Crecimiento/patología , Intestino Delgado/patología , Estómago/patología , Porcinos , Enfermedades de los Porcinos/diagnóstico , Síndrome , Timo/patología , Destete
15.
Acta Chir Belg ; 115(3): 227-31, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26158256

RESUMEN

Supracolic peri-pancreatic visceral pseudoaneurysms combine the challenges of difficult location for open surgical repair with unpredictable risk of fatal exsanguination. Endovascular embolisation is a well-established method of safely decompressing these lesions using a variety of thrombogenic agents. A single catheter technique is commonly employed to achieve this outcome. However, there is also a risk of iatrogenic rupture during these procedures as a result of occlusion of one vessel allowing pressure to rise through any other vessel(s). Thus a thorough understanding of the flow dynamics prior to and during occlusion is essential for safe decompression. We report the adaptation of dual arterial catheter technique in treating these lesions in an 80-year old man with a large, leaking peripancreatic visceral pseudo-aneurysm. Our technique of alternating between intervention and observation of effect allows greater control of the potentially unpredictable haemodynamic situation.


Asunto(s)
Aneurisma Falso/terapia , Aneurisma Roto/prevención & control , Cateterismo/métodos , Embolización Terapéutica/métodos , Anciano de 80 o más Años , Aneurisma Falso/fisiopatología , Humanos , Masculino , Flujo Sanguíneo Regional , Espacio Retroperitoneal , Tomografía Computarizada por Rayos X , Vísceras/irrigación sanguínea
16.
J Fish Biol ; 85(5): 1746-52, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25230112

RESUMEN

A series of 14 day experiments was conducted on five common New Zealand fish species (redfin bully Gobiomorphus huttoni, inanga Galaxias maculatus, brown trout Salmo trutta, longfin eel Anguilla dieffenbachii and koaro Galaxias brevipinnis) to assess the effect of pH on survival and changes in body mass. No species survived in water of pH <4 although there was 100% survival of all adults at pH 4.5, G. maculatus larvae were also tested and had high mortality at this pH. Results suggest that adults are tolerant of low-pH waters; however, successful remediation of anthropogenically acidified streams will require an understanding of the susceptibility to low pH on different life cycle stages.


Asunto(s)
Anguilla/fisiología , Osmeriformes/fisiología , Trucha/fisiología , Animales , Tamaño Corporal , Agua Dulce , Concentración de Iones de Hidrógeno , Nueva Zelanda
17.
Front Microbiol ; 15: 1352315, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38389522

RESUMEN

The impact of late gestation PRRSV-2 infection is highly variable within a litter, with a subset of fetuses displaying varying degrees of compromise following infection while others remain viable despite significant systemic viral load. To understand the underlying cause of this variation, we examined the susceptibility, distribution and impact of viral infection within non-lymphoid tissues. Samples of brain, heart, kidney, liver, lung, and skeletal muscle were obtained from fetuses of pregnant gilts at gestation day 86, and the presence and distribution of CD163+ cells within each tissue evaluated via immunohistofluorescence. Equivalent samples were collected from phenotypic extremes representing resistant, resilient and susceptible fetuses at 21 days following infection of pregnant gilts with PRRSV-2 at day 86 of gestation. Viral load and its impact in each tissue was evaluated by a combination of qPCR, in vitro viral recovery, and local expression of IFNG and CD163. Resting populations of CD163+ cells were observed in all six non-lymphoid tissues from healthy day 86 fetuses, though the apparent density and the morphology of positive cells varied between tissue. Viral RNA was detected in all six tissues derived from fetuses previously classified as highly infected, and infectious viral particles successfully recovered. Significantly more viral RNA was detected in heart, brain, lung and skeletal muscle of susceptible fetuses, relative to their viable counterparts. Infection was associated with an increase in the expression of CD163 in brain, kidney and lung. In addition, the presence of virus in each tissue coincided with a significant upregulation in the expression of IFNG, but the scale of this response was not associated with fetal susceptibility. Thus, PRRSV-2 is widely distributed across these susceptible non-lymphoid fetal tissues, and fetal outcome is associated with local viral load in critical fetal organs.

18.
Vet Microbiol ; 295: 110154, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38959808

RESUMEN

Porcine reproductive and respiratory syndrome (PRRS) is one of the costliest diseases to pork producers worldwide. We tested samples from the pregnant gilt model (PGM) to better understand the fetal response to in-utero PRRS virus (PRRSV) infection. Our goal was to identify critical tissues and genes associated with fetal resilience or susceptibility. Pregnant gilts (N=22) were infected with PRRSV on day 86 of gestation. At 21 days post maternal infection, the gilts and fetuses were euthanized, and fetal tissues collected. Fetuses were characterized for PRRS viral load in fetal serum and thymus, and preservation status (viable or meconium stained: VIA or MEC). Fetuses (N=10 per group) were compared: uninfected (UNIF; <1 log/µL PRRSV RNA), resilient (HV_VIA, >5 log virus/µL but viable), and susceptible (HV_MEC, >5 log virus/µL with MEC). Gene expression in fetal heart, kidney, and liver was investigated using NanoString transcriptomics. Gene categories investigated were hypothesized to be involved in fetal response to PRRSV infection: renin- angiotensin-aldosterone, inflammatory, transporter and metabolic systems. Following PRRSV infection, CCL5 increased expression in heart and kidney, and ACE2 decreased expression in kidney, each associated with fetal PRRS susceptibility. Liver revealed the most significant differential gene expression: CXCL10 decreased and IL10 increased indicative of immune suppression. Increased liver gene expression indicated potential associations with fetal PRRS susceptibility on several systems including blood pressure regulation (AGTR1), energy metabolism (SLC16A1 and SLC16A7), tissue specific responses (KL) and growth modulation (TGFB1). Overall, analyses of non-lymphoid tissues provided clues to mechanisms of fetal compromise following maternal PRRSV infection.

19.
bioRxiv ; 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38746135

RESUMEN

Kaposi Sarcoma (KS) is a complex tumor caused by KS-associated herpesvirus 8 (KSHV). Histological analysis reveals a mixture of "spindle cells", vascular-like spaces, extravasated erythrocytes, and immune cells. In order to elucidate the infected and uninfected cell types in KS tumors, we examined skin and blood samples from twelve subjects by single cell RNA sequence analyses. Two populations of KSHV-infected cells were identified, one of which represented a proliferative fraction of lymphatic endothelial cells, and the second represented an angiogenic population of vascular endothelial tip cells. Both infected clusters contained cells expressing lytic and latent KSHV genes. Novel cellular biomarkers were identified in the KSHV infected cells, including the sodium channel SCN9A. The number of KSHV positive tumor cells was found to be in the 6% range in HIV-associated KS, correlated inversely with tumor-infiltrating immune cells, and was reduced in biopsies from HIV-negative individuals. T-cell receptor clones were expanded in KS tumors and blood, although in differing magnitudes. Changes in cellular composition in KS tumors were identified in subjects treated with antiretroviral therapy alone, or immunotherapy. These studies demonstrate the feasibility of single cell analyses to identify prognostic and predictive biomarkers. Author Summary: Kaposi sarcoma (KS) is a malignancy caused by the KS-associated herpesvirus (KSHV) that causes skin lesions, and may also be found in lymph nodes, lungs, gastrointestinal tract, and other organs in immunosuppressed individuals more commonly than immunocompetent subjects. The current study examined gene expression in single cells from the tumor and blood of these subjects, and identified the characteristics of the complex mixtures of cells in the tumor. This method also identified differences in KSHV gene expression in different cell types and associated cellular genes expressed in KSHV infected cells. In addition, changes in the cellular composition could be elucidated with therapeutic interventions.

20.
Ultrasound Obstet Gynecol ; 41(4): 383-9, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23288449

RESUMEN

OBJECTIVE: To examine the relationship between prenatal umbilical artery (UA) and internal carotid artery (ICA) Doppler findings and cognitive development at 3 and 6 years in low-birth-weight children. METHODS: This was a study of 209 low-birth-weight (< 10(th) centile) children born after 28 gestational weeks with UA resistance index (RI) measured within 2 weeks before delivery. Children with normal UA- and ICA-RI were defined as small-for-gestational age (SGA) and those with abnormal UA or ICA Doppler findings as having fetal growth restriction (FGR). Cognitive ability at 3 and 6 years' corrected age was assessed using the fourth edition of the Stanford-Binet Intelligence Scale (SBIS) and compared between SGA and FGR groups. An SBIS score < 85 was considered to indicate delayed development. RESULTS: The median gestational age at diagnosis of abnormal fetal growth was 36.6 (range, 28-41) weeks. There were 87 (41.6%) children classified as having FGR and 122 (58.4%) as SGA. The mean global SBIS score at 3 years was 109.4 (SD, 22.8) and at 6 years it was 110.5 (SD, 13.9). Overall, 22 (10.5%) children had delayed development at 3 years. Total SBIS scores and individual domain scores did not differ between FGR and SGA groups at 3 or 6 years and similar proportions in each group had delayed development. CONCLUSION: Abnormal prenatal UA and ICA Doppler findings are not associated with lower developmental scores in low-birth-weight children delivered in the third trimester of pregnancy.


Asunto(s)
Arteria Carótida Interna/diagnóstico por imagen , Desarrollo Infantil/fisiología , Cognición/fisiología , Discapacidades del Desarrollo/diagnóstico por imagen , Retardo del Crecimiento Fetal/diagnóstico por imagen , Arterias Umbilicales/diagnóstico por imagen , Arteria Carótida Interna/embriología , Niño , Preescolar , Discapacidades del Desarrollo/fisiopatología , Retardo del Crecimiento Fetal/fisiopatología , Humanos , Recién Nacido de Bajo Peso , Recién Nacido , Recién Nacido Pequeño para la Edad Gestacional/crecimiento & desarrollo , Pruebas Neuropsicológicas , Ultrasonografía Doppler , Ultrasonografía Prenatal/métodos , Arterias Umbilicales/embriología
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