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1.
Nature ; 565(7739): 324-327, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30651614

RESUMO

Long γ-ray bursts are associated with energetic, broad-lined, stripped-envelope supernovae1,2 and as such mark the death of massive stars. The scarcity of such events nearby and the brightness of the γ-ray burst afterglow, which dominates the emission in the first few days after the burst, have so far prevented the study of the very early evolution of supernovae associated with γ-ray bursts3. In hydrogen-stripped supernovae that are not associated with γ-ray bursts, an excess of high-velocity (roughly 30,000 kilometres per second) material has been interpreted as a signature of a choked jet, which did not emerge from the progenitor star and instead deposited all of its energy in a thermal cocoon4. Here we report multi-epoch spectroscopic observations of the supernova SN 2017iuk, which is associated with the γ-ray burst GRB 171205A. Our spectra display features at extremely high expansion velocities (around 115,000 kilometres per second) within the first day after the burst5,6. Using spectral synthesis models developed for SN 2017iuk, we show that these features are characterized by chemical abundances that differ from those observed in the ejecta of SN 2017iuk at later times. We further show that the high-velocity features originate from the mildly relativistic hot cocoon that is generated by an ultra-relativistic jet within the γ-ray burst expanding and decelerating into the medium that surrounds the progenitor star7,8. This cocoon rapidly becomes transparent9 and is outshone by the supernova emission, which starts to dominate the emission three days after the burst.

2.
Pediatr Res ; 93(1): 78-88, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35428877

RESUMO

BACKGROUND: We aimed to characterize a preclinical model of intraventricular hemorrhage-induced brain damage (IVH-BD) in extremely low birth weight newborns (ELBWN), to identify potential therapeutic targets based on its pathophysiology. METHODS: IVH was induced in 1-day-old (P1) Wistar rats by left periventricular injection of clostridium collagenase (PVCC). At P6, P14, and P45 IVH-BD (area of damage, motor and cognitive deficits, Lactate/N-acetylaspartate ratio), white matter injury (WMI: ipsilateral hemisphere and corpus callosum atrophy, oligodendroglial population and myelin basic protein signal reduction), blood-brain barrier (BBB) dysfunction (occludin and Mfsd2a expression, Gadolinium leakage) and inflammation (TNFα, TLR4, NFkB, and MMP9 expression; immune cell infiltration), excitotoxicity (Glutamate/N-acetylaspartate), and oxidative stress (protein nitrosylation) were assessed. Sham animals were similarly studied. RESULTS: IVH-BD leads to long-term WMI, resulting in motor and cognitive impairment, thus reproducing IVH-BD features in ELBWN. BBB dysfunction with increased permeability was observed at P6 and P14, coincident with an increased inflammatory response with TLR4 overexpression, increased TNFα production, and increased immune cell infiltration, as well as increased excitotoxicity and oxidative stress. CONCLUSIONS: This model reproduced some key hallmarks of IVH-BD in ELBWN. Inflammation associated with BBB dysfunction appears as relevant therapeutic target to prevent IVH-BD-induced WMI. IMPACT: Paraventricular injection of clostridium collagenase (PVCC) to 1-day-old Wistar rats uniquely reproduced the neuroimaging, histologic and functional characteristics of intraventricular hemorrhage-induced brain damage (IVH-BD) in extremely low birth weight newborns (ELBWN). PVCC-induced IVH triggered a prolonged inflammatory response associated with blood-brain barrier increased permeability, which in turn facilitates the infiltration of inflammatory cells. Thus, PVCC led to white matter injury (WMI) resulting in long-term motor and cognitive impairment. This model offers a valuable tool to obtain further insight into the mechanisms of IVH-BD in ELBWN and proposes some key therapeutic targets.


Assuntos
Barreira Hematoencefálica , Lesões Encefálicas , Animais , Ratos , Fator de Necrose Tumoral alfa/metabolismo , Ratos Wistar , Peso ao Nascer , Receptor 4 Toll-Like/metabolismo , Hemorragia Cerebral/complicações , Lesões Encefálicas/etiologia , Inflamação/metabolismo , Colagenases/metabolismo , Colagenases/uso terapêutico
3.
Nature ; 551(7678): 75-79, 2017 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-29094693

RESUMO

Gravitational waves were discovered with the detection of binary black-hole mergers and they should also be detectable from lower-mass neutron-star mergers. These are predicted to eject material rich in heavy radioactive isotopes that can power an electromagnetic signal. This signal is luminous at optical and infrared wavelengths and is called a kilonova. The gravitational-wave source GW170817 arose from a binary neutron-star merger in the nearby Universe with a relatively well confined sky position and distance estimate. Here we report observations and physical modelling of a rapidly fading electromagnetic transient in the galaxy NGC 4993, which is spatially coincident with GW170817 and with a weak, short γ-ray burst. The transient has physical parameters that broadly match the theoretical predictions of blue kilonovae from neutron-star mergers. The emitted electromagnetic radiation can be explained with an ejected mass of 0.04 ± 0.01 solar masses, with an opacity of less than 0.5 square centimetres per gram, at a velocity of 0.2 ± 0.1 times light speed. The power source is constrained to have a power-law slope of -1.2 ± 0.3, consistent with radioactive powering from r-process nuclides. (The r-process is a series of neutron capture reactions that synthesise many of the elements heavier than iron.) We identify line features in the spectra that are consistent with light r-process elements (atomic masses of 90-140). As it fades, the transient rapidly becomes red, and a higher-opacity, lanthanide-rich ejecta component may contribute to the emission. This indicates that neutron-star mergers produce gravitational waves and radioactively powered kilonovae, and are a nucleosynthetic source of the r-process elements.

4.
FASEB J ; 33(11): 12644-12654, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31483997

RESUMO

The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor, largely known for its role in xenobiotic metabolism and detoxification as well as its crucial role as a regulator of inflammation. Here, we have compared a cohort wild-type and AhR-null mice along aging to study the relationship between this receptor and age-associated inflammation, termed as "inflammaging," both at a systemic and the CNS level. Our results show that AhR deficiency is associated with a premature aged phenotype, characterized by early inflammaging, as shown by an increase in plasma cytokines levels. The absence of AhR also promotes the appearance of brain aging anatomic features, such as the loss of the white matter integrity. In addition, AhR-/- mice present an earlier spatial memory impairment and an enhanced astrogliosis in the hippocampus when compared with their age-matched AhR+/+ controls. Importantly, we have found that AhR protein levels decrease with age in this brain structure, strongly suggesting a link between AhR and aging.-Bravo-Ferrer, I., Cuartero, M. I., Medina, V., Ahedo-Quero, D., Peña-Martínez, C., Pérez-Ruíz, A., Fernández-Valle, M. E., Hernández-Sánchez, C., Fernández-Salguero, P. M., Lizasoain, I., Moro, M. A. Lack of the aryl hydrocarbon receptor accelerates aging in mice.


Assuntos
Senilidade Prematura , Envelhecimento , Hipocampo , Receptores de Hidrocarboneto Arílico/deficiência , Envelhecimento/genética , Envelhecimento/metabolismo , Envelhecimento/patologia , Senilidade Prematura/genética , Senilidade Prematura/metabolismo , Senilidade Prematura/patologia , Animais , Feminino , Hipocampo/metabolismo , Hipocampo/patologia , Masculino , Camundongos , Camundongos Knockout , Receptores de Hidrocarboneto Arílico/metabolismo , Memória Espacial
5.
Med Teach ; 42(9): 1051-1057, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32697116

RESUMO

BACKGROUND: Medical curricula have historically been designed in a top-down approach, usually excluding students. While Delphi panels have been used as a tool for medical education curricula design, none have been conducted in Ecuador. In addition, no such approach has ever included students both as panelists and researchers. MATERIAL AND METHODS: Four Delphi panels were developed and conducted using a participatory approach that allowed medical students to take part both as expert panelists and researchers: specifically, students developed the questionnaire and conducted a qualitative synthesis. Questionnaire responses were anonymized and dispatched online to panelists. The information was organized and collected to develop the qualitative syntheses and prepare the final statements. RESULTS: Thirty-two medical students participated between February and May 2018. A total of 32 questions were developed, corresponding to five different categories. For some questions, consensus was reached; for other questions, general statements were obtained.Discussion and conclusion: Developing the questionnaire, responding to it and analyzing the answers allowed students to raise significant concerns regarding medical education topics proposing relevant policy and curricula change. Participatory Delphi panels can be an efficient tool to obtain organized feedback, improve student class involvement, and promote research skills.


Assuntos
Educação de Graduação em Medicina , Educação Médica , Estudantes de Medicina , Currículo , Técnica Delphi , Equador , Humanos
6.
Haematologica ; 104(11): 2249-2257, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30890600

RESUMO

It has been postulated that monitoring measurable residual disease (MRD) could be used as a surrogate marker of progression-free survival (PFS) in chronic lymphocytic leukemia (CLL) patients after treatment with immunochemotherapy regimens. In this study, we analyzed the outcome of 84 patients at 3 years of follow-up after first-line treatment with fludarabine, cyclophosphamide and rituximab (FCR) induction followed by 36 months of rituximab maintenance thearpy. MRD was assessed by a quantitative four-color flow cytometry panel with a sensitivity level of 10-4 Eighty out of 84 evaluable patients (95.2%) achieved at least a partial response or better at the end of induction. After clinical evaluation, 74 patients went into rituximab maintenance and the primary endpoint was assessed in the final analysis at 3 years of follow-up. Bone marrow (BM) MRD analysis was performed after the last planned induction course and every 6 months in cases with detectable residual disease during the 36 months of maintenance therapy. Thirty-seven patients (44%) did not have detectable residual disease in the BM prior to maintenance therapy. Interestingly, 29 patients with detectable residual disease in the BM after induction no longer had detectable disease in the BM following maintenance therapy. After a median followup of 6.30 years, the median overall survival (OS) and PFS had not been reached in patients with either undetectable or detectable residual disease in the BM, who had achieved a complete response at the time of starting maintenance therapy. Interestingly, univariate analysis showed that after rituximab maintenance OS was not affected by IGHV status (mutated vs unmutated OS: 85.7% alive at 7.2 years vs 79.6% alive at 7.3 years, respectively). As per protocol, 15 patients (17.8%), who achieved a complete response and undetectable peripheral blood and BM residual disease after four courses of induction, were allowed to stop fludarabine and cyclophosphamide and complete two additional courses of rituximab and continue with maintenance therapy for 18 cycles. Surprisingly, the outcome in this population was similar to that observed in patients who received the full six cycles of the induction regimen. These data show that, compared to historic controls, patients treated with FCR followed by rituximab maintenance have high-quality responses with fewer relapses and improved OS. The tolerability of this regime is favorable. Furthermore, attaining an early undetectable residual disease status could shorten the duration of chemoimmunotherapy, reducing toxicities and preventing long-term side effects. The analysis of BM MRD after fludarabine-based induction could be a powerful predictor of post-maintenance outcomes in patients with CLL undergoing rituximab maintenance and could be a valuable tool to identify patients at high risk of relapse, influencing further treatment strategies. This trial is registered with EudraCT n. 2007-002733-36 and ClinicalTrials.gov Identifier: NCT00545714.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Neoplasia Residual/diagnóstico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Ciclofosfamida/administração & dosagem , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/etiologia , Leucemia Linfocítica Crônica de Células B/mortalidade , Quimioterapia de Manutenção , Masculino , Pessoa de Meia-Idade , Prognóstico , Indução de Remissão , Rituximab/administração & dosagem , Resultado do Tratamento , Vidarabina/administração & dosagem , Vidarabina/análogos & derivados
7.
Colorectal Dis ; 21(11): 1321-1325, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31230404

RESUMO

AIM: Empty pelvis syndrome and radiation-induced bowel injury are two major clinical issues resulting from the pelvic dead space after pelvic exenteration (PE). In order to avoid these complications, different methods of pelvic floor reconstruction have been proposed. We report our experience on the use of breast prosthesis. METHOD: Fifty-three patients who underwent PE and three who underwent palliative surgery with silicone breast prosthesis placement were included. RESULTS: Forty-seven posterior PE, six total PE and three palliative procedures were identified. Sphincter preservation was feasible in 34 patients (62.3%). There were no deaths. Overall morbidity was 37.5%. There were no complications such as sepsis or obstruction related to the prosthesis. Adjuvant radiotherapy was delivered in 16 cases (30.1%) without any side-effects. Reconstruction of intestinal continuity was possible in 12 patients (36.3%) with sphincter preservation and the prosthesis allowed a prompt identification of the rectal stump. CONCLUSION: Breast prosthesis placement is a simple and safe method to minimize complications resulting from empty pelvis syndrome and can be adopted to exclude bowel loops from the radiation field. Reconstruction of intestinal continuity after resection is also simplified.


Assuntos
Implantes de Mama , Exenteração Pélvica/efeitos adversos , Distúrbios do Assoalho Pélvico/prevenção & controle , Procedimentos de Cirurgia Plástica/métodos , Complicações Pós-Operatórias/prevenção & controle , Implantação de Prótese/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Bases de Dados Factuais , Feminino , Neoplasias dos Genitais Femininos/cirurgia , Humanos , Pessoa de Meia-Idade , Cuidados Paliativos/métodos , Diafragma da Pelve/cirurgia , Distúrbios do Assoalho Pélvico/etiologia , Pelve/cirurgia , Complicações Pós-Operatórias/etiologia , Estudos Prospectivos , Resultado do Tratamento
8.
Ultrasound Obstet Gynecol ; 52(4): 530-534, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29280508

RESUMO

OBJECTIVE: To evaluate whether the freeze-all strategy affects in-vitro fertilization (IVF) outcome in poor ovarian responders (POR) defined according to the Bologna criteria. METHOD: This was a retrospective cohort study of patients undergoing IVF treatment between January 2012 and December 2016 at a single center. A total of 433 POR (as defined by the Bologna criteria) fulfilled criteria and were included in the study; of these, 277 patients underwent fresh embryo transfer (ET) and 156 followed the freeze-all policy. All patients underwent controlled ovarian stimulation (COS) following a gonadotropin-releasing hormone antagonist protocol, and cleavage-stage ET. Main outcome measure was ongoing pregnancy rate. Secondary outcomes included implantation and clinical pregnancy rates. The freeze-all strategy was implemented when the progesterone serum level was > 1.5 ng/mL or the endometrium was < 7 mm on the trigger day, or as per patient preference. Patients with previous failed fresh ET also underwent fresh ET or freeze-all strategy considering the indications mentioned above. RESULTS: Mean maternal age in the freeze-all group was 39.5 ± 3.6 years and in the fresh ET group was 39.7 ± 3.8 years (P = 0.54). Mean number of embryos transferred (nET) was 1.53 ± 0.6 and 1.60 ± 0.6 (P = 0.12) in the freeze-all and fresh ET groups, respectively. Ongoing pregnancy rate did not differ significantly between the freeze-all and fresh ET groups (9.6% vs 10.1%, respectively; relative risk (RR), 0.95; 95% CI, 0.52-1.73), nor did the clinical pregnancy rate (14.1% vs 13.7%, respectively; RR, 1.03; 95% CI, 0.63-1.67). Implantation rate was 9.6% and 9.8% (P = 0.82) in the freeze-all and fresh ET groups, respectively. Logistic regression analysis (including maternal age, antral follicle count, number of retrieved and mature oocytes, nET, and fresh ET vs freeze-all strategy) indicated that maternal age (P < 0.001) and nET (P = 0.039) were the only independent variables associated with ongoing pregnancy rate. CONCLUSIONS: The freeze-all strategy, compared with fresh ET, had no impact on IVF outcomes in POR patients as defined according to the Bologna criteria. Multicenter studies including large numbers of patients should be carried out to confirm the results of this study and reach conclusions about the potential benefits of the freeze-all policy for poor responders. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Criopreservação/estatística & dados numéricos , Implantação do Embrião/fisiologia , Transferência Embrionária/métodos , Fertilização in vitro , Ovário/fisiopatologia , Adulto , Feminino , Humanos , Indução da Ovulação , Formulação de Políticas , Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Resultado do Tratamento
9.
Eur J Nutr ; 57(7): 2501-2511, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28803365

RESUMO

PURPOSE: This study aimed to evaluate the effects of the subchronic consumption of energy drinks and their constituents (caffeine and taurine) in male Wistar rats using behavioural and oxidative measures. METHODS: Energy drinks (ED 5, 7.5, and 10 mL/kg) or their constituents, caffeine (3.2 mg/kg) and taurine (40 mg/kg), either separately or in combination, were administered orally to animals for 28 days. Attention was measured though the ox-maze apparatus and the object recognition memory test. Following behavioural analyses, markers of oxidative stress, including SOD, CAT, GPx, thiol content, and free radicals, were measured in the prefrontal cortex, hippocampus, and striatum. RESULTS: The latency time to find the first reward was lower in animals that received caffeine, taurine, or a combination of both (P = 0.003; ANOVA/Bonferroni). In addition, these animals took less time to complete the ox-maze task (P = 0.0001; ANOVA/Bonferroni), and had better short-term memory (P < 0.01, Kruskal-Wallis). The ED 10 group showed improvement in the attention task, but did not differ on other measures. In addition, there was an imbalance in enzymatic markers of oxidative stress in the prefrontal cortex, the hippocampus, and the striatum. In the group that received both caffeine and taurine, there was a significant increase in the production of free radicals in the prefrontal cortex and in the hippocampus (P < 0.0001; ANOVA/Bonferroni). CONCLUSIONS: Exposure to a combination of caffeine and taurine improved memory and attention, and led to an imbalance in the antioxidant defence system. These results differed from those of the group that was exposed to the energy drink. This might be related to other components contained in the energy drink, such as vitamins and minerals, which may have altered the ability of caffeine and taurine to modulate memory and attention.


Assuntos
Atenção/efeitos dos fármacos , Cafeína/farmacologia , Bebidas Energéticas , Memória/efeitos dos fármacos , Taurina/farmacologia , Animais , Cafeína/administração & dosagem , Bebidas Energéticas/análise , Masculino , Oxirredução , Ratos , Ratos Wistar , Taurina/administração & dosagem
10.
Eur J Cancer Care (Engl) ; 27(4): e12854, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29726050

RESUMO

Breast cancer is the most common neoplasm among women worldwide. Improvements in early detection and treatment have resulted in improved survival rates; however, the continuation of unhealthy behaviours after diagnosis can increase the risk of second primary tumours. The aim of the study was to evaluate the effectiveness of two nurse-led health education interventions aiming at improving dietary behaviours among women diagnosed with breast cancer. Participants (n = 492) were included in a double-blind randomized controlled trial with three arms: a control group received usual care; women in the first intervention group received a booklet containing dietary advice; women in the second intervention group received the same booklet plus a tailored telephone intervention delivered by a trained nurse. One year after the intervention, women in both intervention groups were more likely to adhere to the recommendation of decreasing the consumption of animal fats compared with the control group (OR:5.0; 95% CI:1.5-16.9 and OR:6.6; 95% CI:2.0-22.6, respectively). Moreover, compared with the control group, the adjusted probability of eating the recommended amount of fruit and vegetables was higher in the second intervention group (OR:2.7; 95% CI:1.4-5.3). In summary, the booklet containing dietary advice for breast cancer survivors, either alone or supplemented with a nurse-led telephone intervention, was effective in promoting adherence to diet recommendations.


Assuntos
Neoplasias da Mama/enfermagem , Sobreviventes de Câncer , Dietoterapia , Educação de Pacientes como Assunto/métodos , Padrões de Prática em Enfermagem , Gorduras na Dieta , Método Duplo-Cego , Feminino , Frutas , Humanos , Pessoa de Meia-Idade , Folhetos , Verduras
11.
Exp Brain Res ; 235(11): 3437-3448, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28835990

RESUMO

We previously showed that proprioceptive sensory input from the hindlimbs to the anterior cerebellar cortex of the cat may not be simply organized with respect to a body map, but it may also be distributed to multiple discrete functional areas extending beyond classical body map boundaries. With passive hindlimb stepping movements, cerebellar activity was shown to relate to whole limb kinematics as does the activity of dorsal spinocerebellar tract (DSCT) neurons. For DSCT activity, whole limb kinematics provides a solid functional framework within which information about limb forces, such as those generated during active stepping, may also be embedded. In this study, we investigated this idea for the spinocerebellar cortex activity by examining the activity of cerebellar cortical neurons during both passive bipedal hindlimb stepping and active stepping on a treadmill. Our results showed a functional compartmentalization of cerebellar responses to hindlimb stepping movements depending on the two types of stepping and strong relationships between neural activities and limb axis kinematics during both. In fact, responses to passive and active stepping were generally different, but in both cases their waveforms were related strongly to the limb axis kinematics. That is, the different stepping conditions modified the kinematics representation without producing different components in the response waveforms. In sum, cerebellar activity was consistent with a global kinematics framework serving as a basis upon which detailed information about limb mechanics and/or about individual limb segments might be imposed.


Assuntos
Fenômenos Biomecânicos/fisiologia , Córtex Cerebelar/fisiologia , Membro Posterior/fisiologia , Locomoção/fisiologia , Neurônios/fisiologia , Tratos Espinocerebelares/fisiologia , Animais , Gatos , Eletroencefalografia , Marcha/fisiologia , Técnicas de Patch-Clamp , Células de Purkinje/fisiologia
12.
Nature ; 480(7375): 69-71, 2011 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-22129725

RESUMO

The tidal disruption of a solar-mass star around a supermassive black hole has been extensively studied analytically and numerically. In these events, the star develops into an elongated banana-shaped structure. After completing an eccentric orbit, the bound debris falls into the black hole, forming an accretion disk and emitting radiation. The same process may occur on planetary scales if a minor body passes too close to its star. In the Solar System, comets fall directly into our Sun or onto planets. If the star is a compact object, the minor body can become tidally disrupted. Indeed, one of the first mechanisms invoked to produce strong gamma-ray emission involved accretion of comets onto neutron stars in our Galaxy. Here we report that the peculiarities of the 'Christmas' gamma-ray burst (GRB 101225A) can be explained by a tidal disruption event of a minor body around an isolated Galactic neutron star. This would indicate either that minor bodies can be captured by compact stellar remnants more frequently than occurs in the Solar System or that minor-body formation is relatively easy around millisecond radio pulsars. A peculiar supernova associated with a gamma-ray burst provides an alternative explanation.

13.
Med Vet Entomol ; 31(4): 365-372, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28782121

RESUMO

Rift Valley fever (RVF) is a mosquito-borne disease caused by the Rift Valley fever virus (RVFV). Rift Valley fever affects a large number of species, including human, and has severe impact on public health and the economy, especially in African countries. The present study examined the vector competence of three different European mosquito species, Culex pipiens (Linnaeus, 1758) form molestus (Diptera: Culicidae), Culex pipiens hybrid form and Stegomyia albopicta (= Aedes albopictus) (Skuse, 1894) (Diptera: Culicidae). Mosquitoes were artificially fed with blood containing RVFV. Infection, disseminated infection and transmission efficiency were evaluated. This is the first study to assess the transmission efficiency of European mosquito species using a virulent RVFV strain. The virus disseminated in Cx. pipiens hybrid form and in S. albopicta. Moreover, infectious viral particles were isolated from saliva of both species, showing their RVFV transmission capacity. The presence of competent Cx. pipiens and S. albopicta in Spain indicates that an autochthonous outbreak of RVF may occur if the virus is introduced. These findings provide information that will help health authorities to set up efficient entomological surveillance and RVFV vector control programmes.


Assuntos
Aedes/virologia , Culex/virologia , Insetos Vetores/virologia , Febre do Vale de Rift/transmissão , Animais , Febre do Vale de Rift/virologia , Vírus da Febre do Vale do Rift/fisiologia , Espanha
14.
Vet Dermatol ; 28(5): 456-e104, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28585337

RESUMO

BACKGROUND: Ultramicronized palmitoylethanolamide (PEA-um) has been reported to reduce pruritus and skin lesions in dogs with moderate atopic dermatitis and pruritus. HYPOTHESIS/OBJECTIVES: A canine ex vivo skin model was used to investigate the ability of PEA-um to counteract changes induced by compound 48/80, a well-known secretagogue that causes mast cell degranulation. ANIMALS: Normal skin was obtained from three donor dogs subjected to surgery for reasons unrelated to the study. METHODS: Cultured skin biopsy samples in triplicate were treated with 10 and 100 µg/mL compound 48/80, without or with 30 µM PEA-um. Mast cell (MC) degranulation, histamine release into the culture medium, local microvascular dilatation, epidermal thickness, keratinocyte proliferation and epidermal differentiation markers were evaluated. RESULTS: Exposure of the skin organ culture to PEA-um 24 h before and 72 h concomitantly to compound 48/80 resulted in a significant decrease of degranulating MCs. PEA-um also reduced the histamine content in the culture medium by half, although the effect did not reach statistical significance. PEA-um significantly counteracted vasodilation induced by 100 µg/mL compound 48/80. Finally, PEA-um alone did not induce changes in epidermal thickness, differentiation markers, keratinocyte proliferation, MC density and/or degranulation. CONCLUSIONS AND CLINICAL IMPORTANCE: Collectively, these results support the protective action PEA-um on the skin of dogs undergoing allergic changes.


Assuntos
Etanolaminas/farmacologia , Ácidos Palmíticos/farmacologia , Pele/efeitos dos fármacos , p-Metoxi-N-metilfenetilamina/antagonistas & inibidores , Amidas , Animais , Degranulação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cães , Feminino , Histamina/metabolismo , Queratinócitos/efeitos dos fármacos , Mastócitos/efeitos dos fármacos , Mastócitos/fisiologia , Técnicas de Cultura de Órgãos/métodos , p-Metoxi-N-metilfenetilamina/farmacologia
15.
Phys Rev Lett ; 117(16): 166804, 2016 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-27792363

RESUMO

We investigate Fabry-Perot interference in an ultraclean carbon nanotube resonator. The conductance shows a clear superstructure superimposed onto conventional Fabry-Perot oscillations. A sliding average over the fast oscillations reveals a characteristic slow modulation of the conductance as a function of the gate voltage. We identify the origin of this secondary interference in intervalley and intravalley backscattering processes which involve wave vectors of different magnitude, reflecting the trigonal warping of the Dirac cones. As a consequence, the analysis of the secondary interference pattern allows us to estimate the chiral angle of the carbon nanotube.

16.
Mol Psychiatry ; 20(6): 772-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25824306

RESUMO

Previous studies on the neurocognitive impact of cannabis use have found working and declarative memory deficits that tend to normalize with abstinence. An unexplored aspect of cognitive function in chronic cannabis users is the ability to distinguish between veridical and illusory memories, a crucial aspect of reality monitoring that relies on adequate memory function and cognitive control. Using functional magnetic resonance imaging, we show that abstinent cannabis users have an increased susceptibility to false memories, failing to identify lure stimuli as events that never occurred. In addition to impaired performance, cannabis users display reduced activation in areas associated with memory processing within the lateral and medial temporal lobe (MTL), and in parietal and frontal brain regions involved in attention and performance monitoring. Furthermore, cannabis consumption was inversely correlated with MTL activity, suggesting that the drug is especially detrimental to the episodic aspects of memory. These findings indicate that cannabis users have an increased susceptibility to memory distortions even when abstinent and drug-free, suggesting a long-lasting compromise of memory and cognitive control mechanisms involved in reality monitoring.


Assuntos
Transtornos Cognitivos/etiologia , Simulação de Doença/patologia , Abuso de Maconha , Transtornos da Memória/etiologia , Lobo Temporal/patologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Modelos Lineares , Imageamento por Ressonância Magnética , Masculino , Abuso de Maconha/complicações , Abuso de Maconha/patologia , Abuso de Maconha/psicologia , Testes Neuropsicológicos , Oxigênio/sangue , Escalas de Graduação Psiquiátrica , Lobo Temporal/irrigação sanguínea
17.
Wound Repair Regen ; 24(5): 767-774, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27487792

RESUMO

The present status of clinical leg ulcer healing research was reviewed by 25 experts over 2 days on September 28 and 29, 2015. Multiple clinical effectiveness reviews were presented suggesting that published clinical wound healing research often does not meet present (2015) evidence based standards. Specific areas requiring remediation were highlighted and approaches to overcoming existing challenges were proposed. Participants using anonymous voting technology developed an action plan to resolve perceived deficiencies. Statements were accepted if 75% of participants agreed. Older patients with a high frequency of comorbid conditions posed particular difficulties in designing clinical research protocols and better diagnostic categorization is necessary A standardized model template for collecting information about diagnosis and evaluation of the effect of interventions on healing of all types of leg ulcers was considered a high priority. Such a model template could be modified depending on the specific etiology of the leg ulcers. Generally agreed on quantifiable standards to establish degree of morbidity was considered a high priority. There was universal agreement that sources of funding and conflicts of interest needed to be disclosed in presentations and all publications. All clinical research studies should be registered with appropriate authorities. There was substantial enthusiasm for a clinical research network with quality standards for membership and an advisory research core available to investigators. Such a network should be funded and actively managed to insure long-term viability. The governance of such an entity needs to be established by the wound care community. The present trend to integrate patients into the clinical research process was endorsed and there was enthusiasm to develop patient advocacy for wound healing research.

18.
Br J Nutr ; 116(7): 1229-1235, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27641762

RESUMO

It has been previously shown that Lactobacillus plantarum CRL 2130 is able to produce riboflavin in soyamilk. The aim of the present study was to evaluate the efficiency of this riboflavin-bio-enriched soyamilk to revert and/or prevent the nutritional deficiency of riboflavin using different animal models. When used to supplement the diets of previously depleted animals, it was shown that the growth, riboflavin status and morphology of the small intestines reverted to normal parameters and were similar to animals supplemented with commercial riboflavin. In the prevention model, the same tendency was observed, where animals that received soyamilk fermented with L. plantarum CRL 2130 did not show signs of riboflavin deficiency. This new bio-fortified soya-based product could be used as part of normal diets to provide a more natural alternative to mandatory fortification with riboflavin for the prevention of its deficiency.


Assuntos
Fermentação , Lactobacillus plantarum/metabolismo , Deficiência de Riboflavina/prevenção & controle , Riboflavina/biossíntese , Leite de Soja/química , Animais , Dieta , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Riboflavina/administração & dosagem , Deficiência de Riboflavina/etiologia , Leite de Soja/metabolismo
19.
Oecologia ; 182(2): 595-609, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27272209

RESUMO

Pollen limitation may be an important factor in accelerated decline of sparse or fragmented populations. Little is known whether hydrophilous plants (pollen transport by water) suffer from an Allee effect due to pollen limitation or not. Hydrophilous pollination is a typical trait of marine angiosperms or seagrasses. Although seagrass flowers usually have high pollen production, floral densities are highly variable. We evaluated pollen limitation for intertidal populations of the seagrass Zostera noltei in The Netherlands and found a significant positive relation between flowering spathe density and fruit-set, which was suboptimal at <1200 flowering spathes m(-2) (corresponding to <600 reproductive shoots m(-2)). A fragmented population had ≈35 % lower fruit-set at similar reproductive density than a continuous population. 75 % of all European populations studied over a large latitudinal gradient had flowering spathe densities below that required for optimal fruit-set, particularly in Southern countries. Literature review of the reproductive output of hydrophilous pollinated plants revealed that seed- or fruit-set of marine hydrophilous plants is generally low, as compared to hydrophilous freshwater and wind-pollinated plants. We conclude that pollen limitation as found in Z. noltei may be a common Allee effect for seagrasses, potentially accelerating decline and impairing recovery even after environmental conditions have improved substantially.


Assuntos
Pólen , Polinização , Flores , Magnoliopsida , Reprodução , Sementes
20.
Med Vet Entomol ; 30(2): 166-73, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26890285

RESUMO

The emerging disease West Nile fever is caused by West Nile virus (WNV), one of the most widespread arboviruses. This study represents the first test of the vectorial competence of European Culex pipiens Linnaeus 1758 and Stegomyia albopicta (= Aedes albopictus) (both: Diptera: Culicidae) populations for lineage 1 and 2 WNV isolated in Europe. Culex pipiens and S. albopicta populations were susceptible to WNV infection, had disseminated infection, and were capable of transmitting both WNV lineages. This is the first WNV competence assay to maintain mosquito specimens under environmental conditions mimicking the field (day/night) conditions associated with the period of maximum expected WNV activity. The importance of environmental conditions is discussed and the issue of how previous experiments conducted in fixed high temperatures may have overestimated WNV vector competence results with respect to natural environmental conditions is analysed. The information presented should be useful to policymakers and public health authorities for establishing effective WNV surveillance and vector control programmes. This would improve preparedness to prevent future outbreaks.


Assuntos
Aedes/virologia , Culex/virologia , Insetos Vetores/virologia , Febre do Nilo Ocidental/transmissão , Vírus do Nilo Ocidental/fisiologia , Animais , Culex/genética , Europa (Continente) , Feminino , Insetos Vetores/genética , Espanha , Vírus do Nilo Ocidental/genética
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