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1.
Rev Sci Instrum ; 91(3): 033107, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32259969

RESUMO

Over the past few years, work has been conducted at AWE to accurately characterize x-ray diffraction crystals to allow for absolute measurements of x-ray emission for our Orion opacity campaigns. Diffraction crystals are used in spectrometers on Orion to record the dispersed spectral features emitted by the laser produced plasma to obtain a measurement of the plasma conditions. Previously, based on a Manson x-ray source, our calibration system struggled to attain a high signal at the low energies required in calibration for the use of aluminum as a tracer for higher atomic number experiments. Here, we present data from the newly commissioned CTX400 x-ray source, a twin anode water cooled system, showing it to be a bright source even for ∼1 keV energies. Rocking curve measurements for three of the most commonly used crystals, namely, pentaerythritol, cesium acid phthalate, and germanium, are presented for both convex and flat forms.

3.
Parasitol Res ; 119(3): 1167-1172, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31863180

RESUMO

Precise identification of avian schistosomes in the genus Trichobilharzia at the species level is difficult and requires both traditional morphological and molecular techniques. To obtain satisfactory results by traditional methods, the characteristics of the intact adults or large fragments of male and females are necessary. The present study aimed to introduce a more efficient method for collecting eggs and both fragments and intact worms for morphological identification of visceral Trichobilharzia spp. Thirty-eight domestic ducks (twenty-eight fresh and ten frozen) were studied. For fresh samples, warm saline (40-45 °C) was injected into the portal vein or liver tissue, followed by slicing of the liver to small pieces in a large Petri dish. All materials were then transferred into the laboratory sieves arranged from the largest to the smallest mesh size and while crushed with the hand, washed, and filtered using a trigger water sprayer. The collected materials were studied under a stereomicroscope for parasite eggs, fragments, and full-length worms. Out of 28 freshly killed ducks, 19 (67.9%) and of 10 frozen ducks 6 (60%) were positive for visceral Trichobilharzia spp. The full-length worms and large fragments of male worms were mostly recovered with the mesh no. 150 (diameter of 106 µm) and small fragments, especially of females, and eggs with the mesh no. 270 (diameter of 53 µm). In addition to large numbers of fragments, 15 full-length adults were obtained from fresh and 2 from frozen ducks. The number of collected full-length adults was related to the worm burden. Since morphological description of different species of the genus Trichobilharzia is primarily based on the availability of adult worms, the application of methods that provide a higher number of intact males and females will result in better characterization of the species and deposition of appropriate voucher specimens. These results show the present method as a suitable tool for the collection of quality adults of visceral Trichobilharzia spp. in ducks.


Assuntos
Doenças das Aves/parasitologia , Fígado/parasitologia , Schistosomatidae/isolamento & purificação , Infecções por Trematódeos/veterinária , Animais , Patos/parasitologia , Feminino , Masculino , Schistosomatidae/classificação , Caramujos/parasitologia , Infecções por Trematódeos/parasitologia
4.
J Neurosci ; 40(5): 1145-1161, 2020 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-31836659

RESUMO

Zika virus (ZIKV) infection during pregnancy has been causally linked to a constellation of neurodevelopmental deformities in the fetus resulting in a disease termed congenital Zika syndrome (CZS). Here we detail how ZIKV infection produces extensive neuropathology in the developing mouse brain and spinal cord of both sexes. Surprisingly, neuropathology differs depending on viral strain with a French Polynesian isolate producing primarily excitotoxicity and a Brazilian isolate being almost exclusively apoptotic but occurring over a prolonged period that is more likely to produce severe hypoplasia. We also show exposure can produce a characteristic pattern of infection that mirrors neuropathology and ultimately results in gross morphological deformities strikingly similar to CZS. This research provides a valuable mouse model mirroring the clinical course of disease that can be used to test potential therapies to improve treatment and gain a better understanding of the disabilities associated with CZS.SIGNIFICANCE STATEMENT Zika virus (ZIKV) infection during pregnancy has been causally linked to a constellation of neurodevelopmental deformities in the fetus resulting in a disease termed congenital Zika syndrome. Despite its devastating effects, very little is known about how ZIKV infection produces fetal neuropathology. Here we detail the temporal progression of ZIKV infection in the mouse brain and spinal cord resulting in massive neurodegeneration of infected regions. We also report a ZIKV strain from a region of Brazil with high levels of microcephaly (abnormally small head circumference) produces particularly devastating neuropathology.


Assuntos
Encéfalo/virologia , Neurônios/virologia , Medula Espinal/virologia , Infecção por Zika virus/patologia , Infecção por Zika virus/virologia , Animais , Animais Recém-Nascidos , Apoptose , Encéfalo/crescimento & desenvolvimento , Encéfalo/patologia , Feminino , Masculino , Camundongos Endogâmicos C57BL , Neurônios/patologia , Medula Espinal/crescimento & desenvolvimento , Medula Espinal/patologia , Zika virus/patogenicidade
5.
Neurobiol Dis ; 130: 104489, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31175984

RESUMO

Sedatives and anesthetics can injure the developing brain. They cause apoptosis of neurons and oligodendrocytes, impair synaptic plasticity, inhibit neurogenesis and trigger long-term neurocognitive deficits. The projected vulnerable period in humans extends from the third trimester of pregnancy to the third year of life. Despite all concerns, there is no ethically and medically acceptable alternative to the use of sedatives and anesthetics for surgeries and painful interventions. Development of measures that prevent injury while allowing the medications to exert their desired actions has enormous translational value. Here we investigated protective potential of hypothermia against histological toxicity of the anesthetic sevoflurane in the developing nonhuman primate brain. Neonatal rhesus monkeys underwent sevoflurane anesthesia over 5 h. Body temperature was regulated in the normothermic (>36.5 °C), mild hypothermic (35-36.5 °C) and moderately hypothermic (<35 °C) range. Animals were euthanized at 8 h and brains examined immunohistochemically (activated caspase 3) and stereologically to quantify apoptotic neuronal and oligodendroglial death. Sevoflurane anesthesia was well tolerated at all temperatures, with oxygen saturations, end tidal CO2 and blood gases remaining at optimal levels. Compared to controls, sevoflurane exposed brains displayed significant apoptosis in gray and white matter affecting neurons and oligodendrocytes. Mild hypothermia (35-36.5 °C) conferred significant protection from apoptotic brain injury, whereas moderate hypothermia (<35 °C) did not. Hypothermia ameliorates anesthesia-induced apoptosis in the neonatal primate brain within a narrow temperature window (35-36.5 °C). Protection is lost at temperatures below 35 °C. Given the mild degree of cooling needed to achieve significant brain protection, application of our findings to humans should be explored further.


Assuntos
Anestésicos Inalatórios/toxicidade , Encéfalo/patologia , Hipotermia Induzida/métodos , Sevoflurano/toxicidade , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Macaca mulatta , Neurônios/efeitos dos fármacos , Neurônios/patologia
6.
Neurobiol Dis ; 127: 554-562, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30951850

RESUMO

Apoptosis is triggered in the developing mammalian brain by sedative, anesthetic or antiepileptic drugs during late gestation and early life. Whether human children are vulnerable to this toxicity mechanism remains unknown, as there are no imaging techniques to capture it. Apoptosis is characterized by distinct structural features, which affect the way damaged tissue scatters ultrasound compared to healthy tissue. We evaluated whether apoptosis, triggered by the anesthetic sevoflurane in the brains of neonatal rhesus macaques, can be detected using quantitative ultrasound (QUS). Neonatal (n = 15) rhesus macaques underwent 5 h of sevoflurane anesthesia. QUS images were obtained through the sagittal suture at 0.5 and 6 h. Brains were collected at 8 h and examined immunohistochemically to analyze apoptotic neuronal and oligodendroglial death. Significant apoptosis was detected in white and gray matter throughout the brain, including the thalamus. We measured a change in the effective scatterer size (ESS), a QUS biomarker derived from ultrasound echo signals obtained with clinical scanners, after sevoflurane-anesthesia in the thalamus. Although initial inclusion of all measurements did not reveal a significant correlation, when outliers were excluded, the change in the ESS between the pre- and post-anesthesia measurements correlated strongly and proportionally with the severity of apoptotic death. We report for the first time in vivo changes in QUS parameters, which may reflect severity of apoptosis in the brains of infant nonhuman primates. These findings suggest that QUS may enable in vivo studies of apoptosis in the brains of human infants following exposure to anesthetics, antiepileptics and other brain injury mechanisms.


Assuntos
Apoptose/fisiologia , Encéfalo/diagnóstico por imagem , Sevoflurano/farmacologia , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Feminino , Macaca mulatta , Masculino , Neurônios/efeitos dos fármacos , Oligodendroglia/efeitos dos fármacos , Ultrassonografia
7.
Psychiatry Res ; 264: 104-115, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29627695

RESUMO

The primary objective of this study was to assess feasibility and gather preliminary outcome data on Mindfulness-Based Resilience Training (MBRT) for law enforcement officers. Participants (n = 61) were randomized to either an 8-week MBRT course or a no intervention control group. Self-report and physiological data were collected at baseline, post-training, and three months following intervention completion. Attendance, adherence, post-training participant feedback, and interventionist fidelity to protocol all demonstrated feasibility of MBRT for law enforcement officers. Compared to no intervention controls, MBRT participants experienced greater reductions in salivary cortisol, self-reported aggression, organizational stress, burnout, sleep disturbance, and reported increases in psychological flexibility and non-reactivity at post-training; however, group differences were not maintained at three-month follow-up. This initial randomized trial suggests MBRT is a feasible intervention. Outcome data suggest MBRT targets key physiological, psychological, and health risk factors in law enforcement officers, consistent with the potential to improve officer health and public safety. However, follow-up training or "booster" sessions may be needed to maintain training gains. A fully powered longitudinal randomized trial is warranted.


Assuntos
Agressão/psicologia , Atenção Plena/métodos , Doenças Profissionais/prevenção & controle , Estresse Ocupacional/prevenção & controle , Polícia/psicologia , Adaptação Psicológica , Adulto , Esgotamento Profissional/prevenção & controle , Esgotamento Profissional/psicologia , Estudos de Viabilidade , Feminino , Humanos , Hidrocortisona/análise , Masculino , Doenças Profissionais/psicologia , Estresse Ocupacional/psicologia , Resiliência Psicológica , Fatores de Risco , Comportamento de Redução do Risco , Saliva/química , Transtornos do Sono-Vigília/prevenção & controle , Transtornos do Sono-Vigília/psicologia , Resultado do Tratamento
8.
Vet Pathol ; 53(5): 1067-77, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27090769

RESUMO

Veterinary pathologists working in diagnostic laboratories are sometimes presented with cases involving animal poisonings that become the object of criminal or civil litigation. Forensic veterinary toxicology cases can include cases involving animal cruelty (malicious poisoning), regulatory issues (eg, contamination of the food supply), insurance litigation, or poisoning of wildlife. An understanding of the appropriate approach to these types of cases, including proper sample collection, handling, and transport, is essential so that chain of custody rules are followed and proper samples are obtained for toxicological analysis. Consultation with veterinary toxicologists at the diagnostic laboratory that will be processing the samples before, during, and after the forensic necropsy can help to ensure that the analytical tests performed are appropriate for the circumstances and findings surrounding the individual case.


Assuntos
Patologia Legal , Patologia Veterinária , Intoxicação/veterinária , Toxicologia/métodos , Animais , Autopsia/veterinária , Crime , Patologia Legal/métodos , Patologia Veterinária/métodos , Intoxicação/diagnóstico , Intoxicação/patologia
9.
Neurobiol Dis ; 83: 35-43, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26319366

RESUMO

The external granule layer (EGL) is a proliferative region that produces over 90% of the neurons in the cerebellum but can also malignantly transform into a cerebellar tumor called the medulloblastoma (the most common malignant brain tumor in children). Current dogma considers Hedgehog stimulation a potent proliferative signal for EGL neural progenitor cells (NPCs) and medulloblastomas. However, the Hedgehog pathway also acts as a survival signal in the neural tube where it regulates dorsoventral patterning by controlling NPC apoptosis. Here we show that Hedgehog stimulation is also a potent survival signal in the EGL and medulloblastomas that produces a massive apoptotic response within hours of signal loss in mice. This toxicity can be produced by numerous Hedgehog antagonists (vismodegib, cyclopamine, and jervine) and is Bax/Bak dependent but p53 independent. Finally, since glucocorticoids can also induce EGL and medulloblastoma apoptosis, we show that Hedgehog's effects on apoptosis can occur independent of glucocorticoid stimulation. This effect may play a major role in cerebellar development by directing where EGL proliferation occurs thereby morphologically sculpting growth. It may also be a previously unknown major therapeutic effect of Hedgehog antagonists during medulloblastoma therapy. Results are discussed in terms of their implications for both cerebellar development and medulloblastoma treatment.


Assuntos
Apoptose , Cerebelo/crescimento & desenvolvimento , Cerebelo/metabolismo , Proteínas Hedgehog/fisiologia , Meduloblastoma/metabolismo , Células-Tronco Neurais/metabolismo , Animais , Caspase 3/metabolismo , Fluocinolona Acetonida/administração & dosagem , Fluocinolona Acetonida/análogos & derivados , Fluocinolona Acetonida/metabolismo , Genes p53 , Proteínas Hedgehog/antagonistas & inibidores , Proteínas Hedgehog/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais
10.
Transplant Proc ; 46(5): 1601-5, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24935334

RESUMO

INTRODUCTION: Most studies investigating machine perfusion preservation for heart transplantation perfuse through the aortic root (antegrade), but the coronary sinus (retrograde) is a potential option. We hypothesized that retrograde machine perfusion provides better functional protection than static storage, while avoiding the potential irregular perfusion seen when aortic insufficiency occurs with antegrade perfusion. MATERIALS AND METHODS: Eighteen canine donor hearts were arrested, procured, and stored in modified Celsior solution for 4 hours by using either static storage at 0°C to 4°C (n = 6) or machine perfusion preservation at 5°C via the aortic root (antegrade, n = 6) or coronary sinus (retrograde, n = 6). Lactate and myocardial oxygen consumption were measured in perfused hearts. Hearts were reimplanted and reperfused for 6 hours with hourly function calculated by using the preload recruitable stroke work (PRSW) relation. Myocardial water content was determined at the end of the experiment. RESULTS: Storage lactate levels and myocardial oxygen consumption were comparable in both perfused groups. The PRSW was increased immediately after bypass in the antegrade group (120.6 ± 19.1 mm Hg) compared with the retrograde (75.0 ± 11.3 mm Hg) and static (78.1 ± 10.5 mm Hg) storage groups (P < .05). At the end of reperfusion, PRSW was higher in the retrograde group (69.8 ± 7.4 mm Hg) compared with the antegrade (40.1 ± 6.8 mm Hg) and static (39.9 ± 10.9 mm Hg) storage groups (P < .05). Myocardial water content was similar among groups. CONCLUSIONS: Both antegrade and retrograde perfusion demonstrated excellent functional preservation, at least equivalent to static storage. Initial function was superior in the antegrade group, but the retrograde hearts displayed better function late after reperfusion. Neither perfused group developed significant edema. Machine perfusion preservation is a promising technique for improving results of cardiac transplantation.


Assuntos
Transplante de Coração/veterinária , Animais , Cães , Soluções para Preservação de Órgãos , Consumo de Oxigênio , Perfusão
11.
Aliment Pharmacol Ther ; 40(5): 508-17, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24943863

RESUMO

BACKGROUND: In the northern hemisphere, the incidence of inflammatory bowel diseases (IBD) has a north-south gradient, suggesting a link between ultraviolet (UV) exposure or vitamin D status and the pathogenesis of IBD. AIM: To test the association of UV exposure with the rates and severity of IBD hospitalisation. METHODS: We conducted a retrospective nationwide analysis of 649 932 Crohn's disease (CD), 384 267 ulcerative colitis (UC), and 288 894 297 non-IBD hospitalisations in the US between 1998 and 2010. Mean UV exposure was assigned to each hospitalisation using surface measures from the National Oceanic and Atmospheric Administration. Relative rates across UV exposures were estimated for IBD hospitalisations, prolonged hospitalisations, bowel surgeries and deaths. RESULTS: Among IBD patients, lower UV exposures had increased hospitalisation rates for CD (217.8 vs. 182.5 per 100 000 overall hospitalisations with low and very high UV, respectively; P trend <0.001) and UC (123.2 vs. 113.8 per 100 000; P trend = 0.033). Low UV groups had greater relative rates of prolonged hospitalisations [CD: 1.13, 95% confidence interval (CI) 1.07-1.19; UC: 1.21, 95% CI 1.13-1.30], bowel surgeries (CD: 1.24, 95% CI 1.16-1.32; UC: 1.21, 95% CI 1.09-1.33), and CD deaths (CD: 1.76, 95% CI 1.14-2.71; UC: 1.24, 95% CI 0.92-1.67). Among non-IBD patients, low UV was associated with prolonged hospitalisations (1.09; 95% CI 1.07-1.11) and deaths (1.13; 95% CI 1.09-1.17), but not bowel surgeries (1.01; 95% CI 0.99-1.03). CONCLUSIONS: Lower ultraviolet exposure is associated with greater rates of hospitalisation, prolonged hospitalisation and the need for bowel surgery in IBD. This trend for bowel surgery was not seen with non-IBD encounters.


Assuntos
Colite Ulcerativa/epidemiologia , Doença de Crohn/epidemiologia , Hospitalização/estatística & dados numéricos , Raios Ultravioleta , Adulto , Idoso , Colite Ulcerativa/cirurgia , Doença de Crohn/cirurgia , Exposição Ambiental , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
12.
Phys Rev Lett ; 112(5): 052501, 2014 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-24580588

RESUMO

Excited states in 102Rh, populated in the fusion-evaporation reaction Zr94(11B,3n)102Rh at a beam energy of 36 MeV, were studied using the Indian National Gamma Array spectrometer at Inter University Accelerator Center, New Delhi. The angular correlations and the electromagnetic character of some of the gamma-ray transitions observed were investigated in detail. A new chiral candidate sister band was found. Lifetimes of exited states in both chiral candidate bands of 102Rh were measured for the first time in the A∼100 mass region by means of the Doppler-shift attenuation technique. The derived reduced transition probabilities are compared to the predictions of the two quasiparticles plus triaxial rotor model. Both experimental results and calculations do not support the presence of static chirality in 102Rh.

13.
J Helminthol ; 88(1): 32-40, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23113960

RESUMO

Because the digenetic trematode fauna of Nepal is poorly known, we began to search for schistosomes in and around Chitwan National Park (CNP) of southern Nepal. Both domestic and wild Indian elephants (Elephus maximus) are present, and we found one of two dung samples from wild elephants and 1 of 22 (4.5%) dung samples from domestic elephants to be positive for schistosome eggs. The morphology of the eggs and both cox1 and 28S sequences derived from the eggs/miracidia were consistent with Bivitellobilharzia nairi, reported here for the first time from Nepal. Also, 7 of 14 faecal samples from the Asian or greater one-horned rhinoceros (Rhinoceros unicornis) contained viable eggs indistinguishable from those of B. nairi. This identification was confirmed by comparison with both cox1 and 28S sequences from B. nairi eggs/miracidia derived from Nepalese and Sri Lankan elephants. This represents the first sequence-verified identification of a schistosome from any species of rhinoceros, and the first verified occurrence of a representative of Bivitellobilharzia (a genus of 'elephant schistosomes') in mammals other than elephants. Our work suggests that elephants and rhinos share B. nairi in CNP, even though these two members of the 'charismatic megafauna' belong to unrelated mammalian families. Their shared life style of extensive contact with freshwater habitats likely plays a role, although the snail intermediate host and mode of definitive host infection for B. nairi have yet to be documented. This report also supports Bivitellobilharzia as a monophyletic group and its status as a distinct genus within Schistosomatidae.


Assuntos
Elefantes/parasitologia , Perissodáctilos/parasitologia , Schistosomatidae/isolamento & purificação , Animais , Complexo IV da Cadeia de Transporte de Elétrons/genética , Fezes/parasitologia , Dados de Sequência Molecular , Nepal , RNA Ribossômico 28S/genética , Schistosomatidae/anatomia & histologia , Schistosomatidae/classificação , Schistosomatidae/genética , Análise de Sequência de DNA
14.
Brain Res ; 1545: 54-63, 2014 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-24361977

RESUMO

Respiratory dysfunction is one of the most common causes of death associated with premature birth (Barton et al., 1999). In the United States, 7-10% of pregnant women receive antenatal glucocorticoid (GC) therapy (Matthews et al., 2004), while approximately 19% of very low birth weight infants receive postnatal GC therapy (Jobe, 2009). Clinical research suggests that GC treatment causes permanent neuromotor and cognitive deficits (Yeh et al., 2004) and stunts cerebellar growth (Parikh et al., 2007; Tam et al., 2011). We previously reported that GC-mediated neural progenitor cell (NPC) apoptosis may be responsible for cerebellar neuropathology (Maloney et al., 2011; Noguchi et al., 2008, 2011). The goal of the current study was to determine whether lithium protects NPCs from GC neuroapoptosis in vivo and in vitro. Given that it protects against a range of brain insults, we hypothesized that lithium would significantly attenuate GC induced NPC toxicity. We report that acute lithium pretreatment provides potent, cell-intrinsic neuroprotection against GC induced NPC toxicity in vivo and in vitro.


Assuntos
Apoptose/efeitos dos fármacos , Cerebelo/efeitos dos fármacos , Dexametasona/toxicidade , Glucocorticoides/toxicidade , Carbonato de Lítio/uso terapêutico , Cloreto de Lítio/uso terapêutico , Células-Tronco Neurais/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Animais , Células Cultivadas , Cerebelo/crescimento & desenvolvimento , Camundongos
15.
Genes Immun ; 14(5): 310-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23615072

RESUMO

The Ashkenazi Jewish population has a several-fold higher prevalence of Crohn's disease (CD) compared with non-Jewish European ancestry populations and has a unique genetic history. Haplotype association is critical to CD etiology in this population, most notably at NOD2, in which three causal, uncommon and conditionally independent NOD2 variants reside on a shared background haplotype. We present an analysis of extended haplotypes that showed significantly greater association to CD in the Ashkenazi Jewish population compared with a non-Jewish population (145 haplotypes and no haplotypes with P-value <10(-3), respectively). Two haplotype regions, one each on chromosomes 16 and 21, conferred increased disease risk within established CD loci. We performed exome sequencing of 55 Ashkenazi Jewish individuals and follow-up genotyping focused on variants in these two regions. We observed Ashkenazi Jewish-specific nominal association at R755C in TRPM2 on chromosome 21. Within the chromosome 16 region, R642S of HEATR3 and rs9922362 of BRD7 showed genome-wide significance. Expression studies of HEATR3 demonstrated a positive role in NOD2-mediated NF-κB signaling. The BRD7 signal showed conditional dependence with only the downstream rare CD-causal variants in NOD2, but not with the background haplotype; this elaborates NOD2 as a key illustration of synthetic association.


Assuntos
Doença de Crohn/genética , Judeus/genética , Mutação de Sentido Incorreto , NF-kappa B/genética , Proteínas/genética , Transdução de Sinais/genética , Proteínas Cromossômicas não Histona/genética , Cromossomos Humanos Par 16/genética , Éxons/genética , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla , Genótipo , Células HEK293 , Haplótipos , Humanos , Modelos Logísticos , Proteína Adaptadora de Sinalização NOD2/genética , Polimorfismo de Nucleotídeo Único , Interferência de RNA , Análise de Sequência de DNA
16.
J Helminthol ; 87(1): 102-7, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22339846

RESUMO

One of the most poorly known of all schistosomes infecting mammals is Bivitellobilharzia loxodontae. Nearly all of our available information about this species comes from the original description of worms that were obtained from an animal park-maintained elephant in Germany, probably a forest elephant Loxodonta cyclotis, originating from the present-day Democratic Republic of Congo. We obtained schistosome eggs from faecal samples from wild forest elephants from the Central African Republic. The eggs, which were similar in size and shape to those of described B. loxodontae, were sequenced for the 28S nuclear ribosomal gene and the mitochondrial cytochrome oxidase I (cox1) gene. In a phylogenetic analysis of 28S sequences, our specimens grouped closely with B. nairi, the schistosome from the Indian elephant Elephas maximus, to the exclusion of schistosomes from other genera. However, the eggs were genetically distinct (12% distance cox1) from those of B. nairi. We conclude the specimens we recovered were of B. loxodontae and confirm this is a distinct Bivitellobilharzia species. In addition to providing the first sequence data for B. loxodontae, this report also supports Bivitellobilharzia as a monophyletic group and gives the relative phylogenetic position of the genus within the Schistosomatidae. We also provide a review of the biology of this poorly known schistosome genus.


Assuntos
Schistosomatidae/classificação , Schistosomatidae/genética , Infecções por Trematódeos/veterinária , Animais , República Centro-Africana , Análise por Conglomerados , DNA de Helmintos/química , DNA de Helmintos/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Elefantes , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 28S/genética , Schistosomatidae/isolamento & purificação , Análise de Sequência de DNA , Infecções por Trematódeos/parasitologia
17.
Pediatr Res ; 71(1): 54-62, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22289851

RESUMO

INTRODUCTION: Propylene glycol (PG) is a common solvent used in medical preparations. It is generally recognized as safe at regulated concentrations; however, its apoptotic potential is unknown. RESULTS: PG triggered widespread apoptotic neurodegeneration with the greatest damage at postnatal day 7 (P7). Significant apoptosis was observed at doses as low as 2 ml/kg. These findings have implications for the safety of drug preparations used in pediatric medicine. The anticonvulsant phenobarbital (PB), which alone produces apoptosis in the immature central nervous system (CNS) is prepared in 68% PG and 10% ethanol (EtOH). We assessed whether PG contributes to the neurotoxic potential of PB. The agents (both at subtoxic doses) produce significantly more apoptosis when used in combination. DISCUSSION: In conclusion, finding an alternative non-apoptotic solvent that can be used as a substitute for PG may be beneficial to patients. METHODS: C57BL/6 mice (P4-30) were exposed to PG to examine whether PG could produce apoptosis in the developing CNS.


Assuntos
Anticonvulsivantes/farmacologia , Apoptose/efeitos dos fármacos , Encéfalo , Fenobarbital/farmacologia , Propilenoglicol/farmacologia , Solventes/farmacologia , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/crescimento & desenvolvimento , Encéfalo/patologia , Caspase 3/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Degeneração Neural/induzido quimicamente , Degeneração Neural/patologia
18.
Neurobiol Dis ; 43(2): 356-63, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21530661

RESUMO

Glucocorticoids are used to treat respiratory dysfunction associated with premature birth but have been shown to cause neurodevelopmental deficits when used therapeutically. Recently, we established that acute glucocorticoid exposure at clinically relevant doses produces neural progenitor cell apoptosis in the external granule layer of the developing mouse cerebellum and permanent decreases in the number of cerebellar neurons. As the cerebellum naturally matures and neurogenesis is no longer needed, the external granule layer decreases proliferation and permanently disappears during the second week of life. At this same time, corticosterone (the endogenous rodent glucocorticoid) release increases and a glucocorticoid-metabolizing enzyme that protects the external granule layer against glucocorticoid receptor stimulation (11ß-Hydroxysteroid-Dehydrogenase-Type 2; HSD2) naturally disappears. Here we show that HSD2 inhibition and raising corticosterone to adult physiological levels both can independently increase neural progenitor cell apoptosis in the neonatal mouse. Conversely, glucocorticoid receptor antagonism decreases natural physiological apoptosis in this same progenitor cell population suggesting that endogenous glucocorticoid stimulation may regulate apoptosis in the external granule layer. We also found that glucocorticoids which HSD2 can effectively metabolize generate less external granule layer apoptosis than glucocorticoids this enzyme is ineffective at breaking down. This finding may explain why glucocorticoids that this enzyme can metabolize are clinically effective at treating respiratory dysfunction yet seem to produce no neurodevelopmental deficits. Finally, we demonstrate that both acute and chronic glucocorticoid exposures produce external granule layer apoptosis but without appropriate control groups this effect becomes masked. These results are discussed in terms of their implications for glucocorticoid therapy and neurodevelopment during the perinatal period.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 2/metabolismo , Apoptose/fisiologia , Cerebelo/metabolismo , Receptores de Glucocorticoides/metabolismo , Células-Tronco/metabolismo , 11-beta-Hidroxiesteroide Desidrogenase Tipo 2/antagonistas & inibidores , 11-beta-Hidroxiesteroide Desidrogenase Tipo 2/biossíntese , Animais , Animais Recém-Nascidos , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Cerebelo/citologia , Cerebelo/crescimento & desenvolvimento , Corticosterona/biossíntese , Corticosterona/fisiologia , Camundongos , Camundongos Endogâmicos ICR , Neurogênese/efeitos dos fármacos , Neurogênese/fisiologia , Receptores de Glucocorticoides/antagonistas & inibidores , Receptores de Glucocorticoides/biossíntese , Células-Tronco/citologia
19.
J Parasitol ; 97(5): 946-9, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21506803

RESUMO

Here we provide the first North American report of a naturally infected snail, Gyraulus parvus, harboring the larval stages of the cosmopolitan, arterial schistosome, Dendritobilharzia pulverulenta. The relatively small cercariae of this species are shed in the early morning, are sticky, and adhere to the water's surface film. We also provide a report of the snail host, Physa gyrina, of the widespread North American passerine schistosome, Gigantobilharzia huronensis. Finally, we provide unambiguous documentation that Physa gyrina is a natural snail host for Trichobilharzia querquedulae, a schistosome primarily of dabbling ducks.


Assuntos
Schistosomatidae/classificação , Caramujos/parasitologia , Animais , Doenças das Aves/parasitologia , Doenças das Aves/transmissão , Aves , DNA de Helmintos/química , Água Doce , Funções Verossimilhança , Filogenia , Schistosomatidae/genética , Schistosomatidae/fisiologia , Caramujos/classificação , Infecções por Trematódeos/transmissão , Infecções por Trematódeos/veterinária
20.
Genes Immun ; 11(7): 573-83, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20445568

RESUMO

Reduced cytotoxic T-lymphocyte antigen 4 (CTLA4) expression has been proposed as a risk for autoimmunity. CTLA4 polymorphisms have been associated with several autoimmune diseases, including ulcerative colitis (UC). In this study, we performed genotyping for CTLA4 -1661A/G, -1722T/C and 3' untranslated region (AT)n repeat polymorphisms in 300 Chinese UC patients and in 700 healthy controls, and evaluated the effects of polymorphisms on full-length (flCTLA4) and soluble CTLA4 (sCTLA4) expression in UC patients. The frequency of the -1661G allele was higher in UC patients than in healthy controls (16.5 vs 11.4%, P=0.003, odds ratio (OR)=1.53, 95% confidence interval (95% CI): 1.17-2.01). The prevalence of (AT)n repeats of the CTLA4 gene carrying long alleles (≥116 bp) was more common in UC patients than in healthy controls (22.0 vs 6.3%, P<0.001, OR=4.21, 95% CI: 2.79-6.33), and was associated with extensive colitis (P=0.008). Among UC patients, long-allele carriers expressed lower levels of flCTLA4 and sCTLA4 mRNA and sCTLA4 protein than did short-allele carriers (P<0.001, P<0.001, P<0.001, respectively). CTLA4 gene -1661A/G and long 3' untranslated region (AT)n repeat polymorphisms are associated with UC in Central China. This is likely from decreased expressions of sCTLA4 mRNA and sCTLA4 protein. Our study suggests that CTLA4 has an important role in susceptibility for UC in Central China.


Assuntos
Regiões 3' não Traduzidas/genética , Antígenos CD/genética , Colite Ulcerativa/genética , Polimorfismo Genético , Adulto , Alelos , Antígenos CD/metabolismo , Povo Asiático/genética , Antígeno CTLA-4 , Estudos de Casos e Controles , China/epidemiologia , Colite Ulcerativa/epidemiologia , Colite Ulcerativa/imunologia , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , RNA Mensageiro/genética , RNA Mensageiro/imunologia , Solubilidade
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