Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 448
Filtrar
1.
Geophys Res Lett ; 47(20): e2020GL090115, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33380758

RESUMO

The solar wind is slowed, deflected, and heated as it encounters Venus's induced magnetosphere. The importance of kinetic plasma processes to these interactions has not been examined in detail, due to a lack of constraining observations. In this study, kinetic-scale electric field structures are identified in the Venusian magnetosheath, including plasma double layers. The double layers may be driven by currents or mixing of inhomogeneous plasmas near the edge of the magnetosheath. Estimated double-layer spatial scales are consistent with those reported at Earth. Estimated potential drops are similar to electron temperature gradients across the bow shock. Many double layers are found in few high cadence data captures, suggesting that their amplitudes are high relative to other magnetosheath plasma waves. These are the first direct observations of plasma double layers beyond near-Earth space, supporting the idea that kinetic plasma processes are active in many space plasma environments.

2.
Anaesth Rep ; 8(1): 48-51, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32537611

RESUMO

Major complications of laryngoscopy and tracheal intubation are rare. However, mucosal trauma during airway management can lead to the introduction of oropharyngeal bacterial flora into the deep neck spaces, with the potential for fatal complications. This report describes the development of a paratracheal abscess in a healthy 62-year-old man following an outpatient herniorrhaphy. The patient was treated with intravenous antibiotics and underwent ultrasound-guided needle aspiration of the abscess. He was later re-admitted to the hospital with re-accumulation of the abscess, which was successfully treated by open surgical drainage. Though deep neck space infection following laryngoscopy is more common in patients with significant comorbidities and when tracheal intubation has been difficult, this case highlights the need for careful airway management in all patients.

3.
Poult Sci ; 99(5): 2452-2458, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32359580

RESUMO

Studies were conducted to determine the efficacy of synbiotic applications to combat the negative effects of necrotic enteritis (NE). An in vitro study was conducted to test the effect of probiotics species supernatants to decrease Clostridium perfringens (CP) proliferation. Lactobacillus reuteri, Enterococcus faecium, Bifidobacterium animalis, and Pediococcus acidilactici culture supernatants decreased the proliferation of CP at 1:1 supernatant-to-pathogen dilution in vitro. Two in vivo studies were conducted to determine the in vivo response of synbiotic supplementation containing the aforementioned probiotic strains on broiler production performance and caecal CP load in broilers induced with NE infection. In experiment 1, 75 broiler chicks were randomly allotted to 3 treatment groups, control (basal diet), ionophore (Salinomycin), and synbiotic (PoultryStar me), from day of hatch, and NE was induced in all birds. There were no significant treatment effects on BW, feed consumption, and feed gain ratio. However, at 35 D, ionophore or synbiotic supplementation increased (P < 0.05) villi height and decreased interleukin (IL)-1 mRNA abundance, while synbiotic supplementation increased (P < 0.05) IL-10 mRNA abundance compared with the control group, respectively. In experiment 2, 360 broiler chicks were randomly allotted to 3 treatments, an unchallenged negative control (control; basal diet), challenged positive control (NE; basal diet), or NE + synbiotic group (synbiotic). At both 21 and 42 D of age, NE birds had decreased (P < 0.05) BW, feed conversion, and jejunal villi height compared with control, while NE + synbiotic birds were not different from control groups. At 42 D of age, NE birds had 2.2 log/g increased CP in the ceca contents compared with control, while synbiotic birds had CP load that was not different than that of the control group. NE + synbiotic birds had significantly greater amounts of bile anti-CP IgA than the control and NE groups. It can be concluded that synbiotic supplementation decreased CP proliferation in vitro and caecal CP load in vivo while improving production parameters during an NE infection in broilers.


Assuntos
Carga Bacteriana , Galinhas , Infecções por Clostridium/veterinária , Clostridium perfringens/efeitos dos fármacos , Doenças das Aves Domésticas/prevenção & controle , Simbióticos/administração & dosagem , Ração Animal/análise , Animais , Carga Bacteriana/efeitos dos fármacos , Ceco/microbiologia , Infecções por Clostridium/microbiologia , Infecções por Clostridium/prevenção & controle , Clostridium perfringens/fisiologia , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Doenças das Aves Domésticas/microbiologia , Distribuição Aleatória
4.
PLoS One ; 14(10): e0223577, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31600299

RESUMO

In vitro and in vivo experiments were conducted to study the effects of synbiotic supplementation on Salmonella enterica ser. Enteritidis (SE) proliferation, cecal content load, and broiler carcass contamination. Lactobacillus reuteri, Enterococcus faecium, Bifidobacterium animalis, and Pediococcus acidilactici culture supernatants decreased (P < 0.05) the in vitro proliferation of SE at 1:1 supernatant: pathogen dilution. A total of 240 Cobb-500 broiler chicks were randomly allotted to three treatment groups (8 replicates/group with 10 birds/replicate): control (basal diet), antibiotic (Virginiamycin at 20 mg/kg feed), synbiotic (PoultryStar® ME at 0.5 g/kg feed containing L. reuteri, E. faecium, B. animalis, P. acidilactici and a Fructooligosaccharide) from day of hatch. At 21 d of age, all birds in experimental groups were orally inoculated with 250 µl of 1 X 109 CFU SE. Antibiotic supplementation increased (P < 0.05) body weight and feed consumption, compared to the control group. Birds in the synbiotic supplementation had intermediate body weight and feed consumption that were not significantly different from both the control and antibiotic group at 42 d of age in SE infected birds. No significant effects were observed in feed efficiency at 42 d of age among the groups. Antibiotic and synbiotic supplementation decreased (P < 0.05) SE load in cecal contents by 0.90 and 0.85 log units/ g and carcass SE load by 1.4 and 1.5 log units/mL of rinsate compared to the control group at 42 d of age (21 dpi). The relative abundance of IL-10, IL-1, TLR-4, and IFNγ mRNA was decreased (P < 0.05) in the antibiotic and synbiotic supplementation groups compared to the control birds at 42 d of age (21 dpi). It can be concluded that synbiotic supplementation decreased SE proliferation in vitro and decreased SE load in the cecal contents and broiler carcass.


Assuntos
Galinhas/microbiologia , Suplementos Nutricionais , Intestinos/microbiologia , Salmonella/crescimento & desenvolvimento , Simbióticos/administração & dosagem , Animais , Ceco/microbiologia , Galinhas/genética , Regulação da Expressão Gênica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Salmonelose Animal/microbiologia
5.
Anaesthesia ; 74(10): 1282-1289, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31273760

RESUMO

The measurement of extravascular lung water is a relatively new technology which has not yet been well validated as a clinically useful tool. We studied its utility in patients undergoing pulmonary endarterectomy as they frequently suffer reperfusion lung injury and associated oedematous lungs. Such patients are therefore ideal for evaluating this new monitor. We performed a prospective observational cohort study during which extravascular lung water index measurements were taken before and immediately after surgery and postoperatively in intensive care. Data were analysed for 57 patients; 21 patients (37%) experienced severe reperfusion lung injury. The first extravascular lung water index measurement after cardiopulmonary bypass failed to predict severe reperfusion lung injury, area under the receiver operating characteristic curve 0.59 (95%CI 0.44-0.74). On intensive care, extravascular lung water index correlated most strongly at 36 h, area under the receiver operating characteristic curve 0.90 (95%CI 0.80-1.00). Peri-operative extravascular lung water index is not a useful measure to predict severe reperfusion lung injury after pulmonary endarterectomy, however, it does allow monitoring and measurement during the postoperative period. This study implies that extravascular lung water index can be used to directly assess pulmonary fluid overload and that monitoring patients by measuring extravascular lung water index during their intensive care stay is useful and correlates with their clinical course. This may allow directed, pre-empted therapy to attenuate the effects and improve patient outcomes and should prompt further studies.


Assuntos
Endarterectomia/efeitos adversos , Água Extravascular Pulmonar , Lesão Pulmonar/diagnóstico , Complicações Pós-Operatórias/diagnóstico , Artéria Pulmonar/cirurgia , Traumatismo por Reperfusão/diagnóstico , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Edema Pulmonar/diagnóstico , Edema Pulmonar/etiologia , Curva ROC , Termodiluição
6.
J Thromb Haemost ; 17(2): 383-388, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30552743

RESUMO

Essentials Current risk scores for heparin-induced thrombocytopenia (HIT) are not computer-friendly. We compared a new computerized risk score with the 4Ts score in a large healthcare system. The computerized risk score agrees with the 4Ts score 85% of the time. The new score could potentially improve HIT diagnosis via incorporation into decision support. SUMMARY: Background (HIT) is an immune-mediated adverse drug event associated with life-threatening thrombotic complications. The 4Ts score is widely used to estimate the risk for HIT and guide diagnostic testing, but it is not easily amenable to computerized clinical decision support (CDS) implementation. Objectives Our main objective was to develop an HIT computerized risk (HIT-CR) scoring system that provides platelet count surveillance for timing and degree of thrombocytopenia to identify those for whom diagnostic testing should be considered. Our secondary objective was to evaluate clinical management and subsequent outcomes in those identified as being at risk for HIT. Methods We retrospectively analyzed data from a stratified sample of 150 inpatients treated with heparin to compare the performance of the HIT-CR scoring system with that of a clinically calculated 4Ts score. We took a 4Ts score of ≥ 4 as the gold standard to determine whether HIT diagnostic testing should be performed. Results The best cutoff point of the HIT-CR score was a score of 3, which yielded 85% raw agreement with the 4Ts score and a kappa of 0.69 (95% confidence interval 0.57-0.81). Ninety per cent of patients with 4Ts score of ≥ 4 failed to undergo conventionally recommended diagnostic testing; 38% of these experienced persistent, unexplained thrombocytopenia, and 4% suffered life-threatening thrombotic complications suggestive of undiagnosed HIT. Conclusion The HIT-CR scoring system is practical for computerized CDS, agrees well with the 4Ts score, and should be prospectively evaluated for its ability to identify patients who should be tested for HIT.


Assuntos
Anticoagulantes/efeitos adversos , Plaquetas/efeitos dos fármacos , Simulação por Computador , Técnicas de Apoio para a Decisão , Heparina/efeitos adversos , Contagem de Plaquetas , Trombocitopenia/induzido quimicamente , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Registros Eletrônicos de Saúde , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Valor Preditivo dos Testes , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Trombocitopenia/sangue , Trombocitopenia/diagnóstico , Adulto Jovem
7.
J Anim Sci ; 96(1): 85-97, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-29378029

RESUMO

Porcine epidemic diarrhea virus (PEDV) infects enterocytes and in nursery pigs, results in diarrhea, anorexia, and reduced performance. Therefore, the objective of this study was to determine how PEDV infection influenced growth performance and repartitioning of amino acids and energy in nursery pigs. A total of 32 barrows and gilts, approximately 1 wk post-wean (BW = 8.46 ± 0.50 kg), and naïve for PEDV were obtained, weighed, and allotted based on sex and BW to one of two treatments: 1) Control, PEDV naïve and 2) PEDV-inoculated (PEDV) with eight pens of two pigs each per treatment. On day post-inoculation (dpi) 0, PEDV pigs were inoculated via intragastric gavage with PEDV isolate (USA/Iowa/18984/2013). Pig and feeder weights were recorded at dpi -7, 0, 5, and 20 in order to calculate ADG, ADFI, and G:F. Eight pigs per treatment were euthanized on dpi 5 and 20, and tissues and blood were collected. At dpi 5, all PEDV pigs were PCR positive for PEDV in feces. Overall, PEDV pigs tended (P < 0.10) to increase ADFI, which resulted in reduced (P < 0.05) feed efficiency. At dpi 5, PEDV pigs had reduced (P < 0.05) villus height and increased (P < 0.05) stem cell proliferation in the jejunum compared with Control pigs. Pigs inoculated with PEDV had increased (P < 0.05) serum haptoglobin and increased insulin-to-glucose ratios compared with Control pigs at dpi 5. Markers of muscle proteolysis were not different (P > 0.05) between treatments within dpi; however, at dpi 5, 20S proteasome activity was increased (P < 0.05) in longissimus dorsi of PEDV pigs compared with Control pigs. Liver and jejunum gluconeogenic enzyme activities were not different (P > 0.05) between treatments within dpi. Overall, PEDV-inoculated pigs did recover the absorptive capacity that was reduced during PEDV infection by increasing proliferation of intestinal stem cells. However, the energy and nutrients needed to recover the epithelium may be originating from available luminal nutrients instead of muscle proteolysis and gluconeogenesis. This study provides insight into the effects of an enteric coronavirus on postabsorptive metabolism in nursery pigs.


Assuntos
Aminoácidos , Infecções por Coronavirus/veterinária , Metabolismo Energético , Vírus da Diarreia Epidêmica Suína/isolamento & purificação , Doenças dos Suínos/virologia , Aminoácidos/metabolismo , Animais , Proliferação de Células , Infecções por Coronavirus/metabolismo , Infecções por Coronavirus/virologia , Diarreia/metabolismo , Diarreia/veterinária , Diarreia/virologia , Fezes/virologia , Feminino , Jejuno/virologia , Masculino , Vírus da Diarreia Epidêmica Suína/genética , Células-Tronco/fisiologia , Suínos , Doenças dos Suínos/metabolismo , Desmame
8.
Vet Microbiol ; 211: 58-66, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29102122

RESUMO

The pig intestinal epithelium can be compromised by pathogens leading to reduced integrity and function. Porcine epidemic diarrhea virus (PEDV), recently detected in North America, exemplifies intestinal epithelial insult. Although several studies have investigated the molecular aspects and host immune response to PEDV, there are little data on the impact of PEDV on pig intestinal physiology. The objective of this study was to investigate the longitudinal impact of PEDV on nursery pig intestinal function and integrity. Fifty recently-weaned, 5-week-old barrows and gilts (BW=9.92±0.49kg) were sorted based on body weight (BW) and sex into two treatments: 1) Control or 2) PEDV inoculated. At 2, 5, 7, and 14days post inoculation (dpi), 4 pigs per treatment were euthanized and jejunum sections collected. PEDV antigen was detected in inoculated pigs by immunohistochemistry in 50% (2/4) at dpi 2, 100% (4/4) at dpi 5, and none at later time points. PEDV-infected pigs had reduced (P<0.05) villus height and decreased transepithelial resistance compared with controls. Total acidic mucins, particularly sialomucin, were reduced in PEDV pigs at dpi 2 and then increased compared with controls at dpi 7 and 14. In addition, PEDV pigs had increased stem cell proliferation (P<0.05) and a numerical increase in DNA fragmentation compared with controls through dpi 7 which coincided with an observed return of digestive function to that of controls. Collectively, these data reveal that PEDV infection results in time-dependent changes not only in intestinal morphology but also barrier integrity and function.


Assuntos
Infecções por Coronavirus/veterinária , Diarreia/veterinária , Vírus da Diarreia Epidêmica Suína/fisiologia , Doenças dos Suínos/fisiopatologia , Animais , Apoptose , Proliferação de Células , Infecções por Coronavirus/fisiopatologia , Infecções por Coronavirus/virologia , Diarreia/fisiopatologia , Diarreia/virologia , Mucosa Intestinal/fisiopatologia , Mucosa Intestinal/virologia , Intestinos/fisiopatologia , Intestinos/virologia , Jejuno/fisiopatologia , Jejuno/virologia , Estudos Longitudinais , Masculino , Vírus da Diarreia Epidêmica Suína/isolamento & purificação , Suínos , Doenças dos Suínos/virologia , Desmame
9.
J Thromb Haemost ; 15(8): 1640-1645, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28622439

RESUMO

Essentials We previously published a diagnostic algorithm for heparin-induced thrombocytopenia (HIT). In this study, we validated the algorithm in an independent large healthcare system. The accuracy was 98%, sensitivity 82% and specificity 99%. The algorithm has potential to improve accuracy and efficiency in the diagnosis of HIT. SUMMARY: Background Heparin-induced thrombocytopenia (HIT) is a life-threatening drug reaction caused by antiplatelet factor 4/heparin (anti-PF4/H) antibodies. Commercial tests to detect these antibodies have suboptimal operating characteristics. We previously developed a diagnostic algorithm for HIT that incorporated 'four Ts' (4Ts) scoring and a stratified interpretation of an anti-PF4/H enzyme-linked immunosorbent assay (ELISA) and yielded a discriminant accuracy of 0.97 (95% confidence interval [CI], 0.93-1.00). Objectives The purpose of this study was to validate the algorithm in an independent patient population and quantitate effects that algorithm adherence could have on clinical care. Methods A retrospective cohort comprised patients who had undergone anti-PF4/H ELISA and serotonin release assay (SRA) testing in our healthcare system from 2010 to 2014. We determined the algorithm recommendation for each patient, compared recommendations with the clinical care received, and enumerated consequences of discrepancies. Operating characteristics were calculated for algorithm recommendations using SRA as the reference standard. Results Analysis was performed on 181 patients, 10 of whom were ruled in for HIT. The algorithm accurately stratified 98% of patients (95% CI, 95-99%), ruling out HIT in 158, ruling in HIT in 10 and recommending an SRA in 13 patients. Algorithm adherence would have obviated 165 SRAs and prevented 30 courses of unnecessary antithrombotic therapy for HIT. Diagnostic sensitivity was 0.82 (95% CI, 0.48-0.98), specificity 0.99 (95% CI, 0.97-1.00), PPV 0.90 (95% CI, 0.56-0.99) and NPV 0.99 (95% CI, 0.96-1.00). Conclusions An algorithm incorporating 4Ts scoring and a stratified interpretation of the anti-PF4/H ELISA has good operating characteristics and the potential to improve management of suspected HIT patients.


Assuntos
Algoritmos , Anticoagulantes/efeitos adversos , Técnicas de Apoio para a Decisão , Fibrinolíticos/uso terapêutico , Heparina/efeitos adversos , Trombocitopenia/diagnóstico , Trombocitopenia/tratamento farmacológico , Anticorpos/sangue , Anticoagulantes/imunologia , Teorema de Bayes , Biomarcadores/sangue , Tomada de Decisão Clínica , Ensaio de Imunoadsorção Enzimática , Heparina/imunologia , Humanos , Fator Plaquetário 4/imunologia , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Trombocitopenia/sangue , Trombocitopenia/induzido quimicamente , Procedimentos Desnecessários
10.
J Anim Sci ; 95(1): 173-181, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28177368

RESUMO

Porcine epidemic diarrhea virus (PEDV) and porcine deltacoronavirus (PDCoV) are both members of the family which induce clinical signs of diarrhea, dehydration, and in some circumstances, mortality. Most research has been focused on isolation, genome sequencing, pathogenicity, and virulence of these viruses, but there is little information on long-term growth performance and tissue accretion of pigs inoculated with PEDV or PDCoV. Therefore, our objective was to determine the effect of PEDV or PDCoV infection on growth performance and tissue accretion over 42 d following inoculation. A total of 75 Choice Genetics Large White Pureline barrows and gilts (BW = 10.81 ± 0.81 kg) at approximately 2 wk post-wean and naïve for PEDV and PDCoV were selected. Pigs were allotted based on BW and sex, stratified across 3 treatments with 8 pens per treatment. Treatments were: 1) Control ( = 8); 2) PEDV inoculated ( = 8); and 3) PDCoV inoculated ( = 8). On day post inoculation (dpi) 2, 5, 7, and 14 pigs were euthanized for tissue collection and analyses from these tissues are discussed elsewhere. Pen feed intake and BW were recorded on dpi 2, 5, 7, and weekly thereafter until dpi 42. On 1 designated pig per pen, initial and final body composition was determined using dual-energy X-ray absorptiometry (DXA) and tissue accretion rates were calculated over 6 wk test period. Peak PEDV infection was noted at 3 dpi compared with 4 dpi for PDCoV pigs as determined by fecal swab quantitative real-time PCR (RT-PCR). Control pigs remained negative for PEDV and PDCoV throughout the experiment. Overall, Control and PDCoV pigs did not differ in ADG, ADFI or G:F ( > 0.05). Compared to Control and PDCoV pigs, the overall 42 d ADFI was reduced in the challenged PEDV pigs ( < 0.05) by 19 and 27%, respectively. PEDV did not significantly reduce the overall ADG or G:F compared with Control and PDCoV pigs; however, the biggest reduction in ADG and ADFI for PEDV pigs was within 14 dpi compared to the Control pigs ( < 0.05). Whole body tissue accretion was altered due to PED, with fat, lean, protein, and bone mineral accretion reductions by 24, 20, 21, and 42%, respectively ( < 0.05) compared with Control pigs. Overall, nursery pig performance was greatly impacted by PEDV challenge. Surprisingly, the PDCoV challenge did not negatively influence nursery pig performance. This study provides further insight into the longitudinal impact swine enteric coronaviruses have on growing pigs.


Assuntos
Infecções por Coronavirus/veterinária , Vírus da Diarreia Epidêmica Suína , Doenças dos Suínos/virologia , Animais , Composição Corporal/efeitos dos fármacos , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Feminino , Masculino , Reação em Cadeia da Polimerase em Tempo Real , Suínos
11.
Cell Death Dis ; 7: e2087, 2016 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-26844701

RESUMO

Colorectal cancer (CRC) is one of the most common cancers in the Western world. 5-Fluorouracil (5FU)-based chemotherapy (CT) remains the mainstay treatment of CRC in the advanced setting, and activates executioner caspases in target cells. Executioner caspases are key proteins involved in cell disassembly during apoptosis. Activation of executioner caspases also has a role in tissue regeneration and repopulation by stimulating signal transduction and cell proliferation in neighbouring, non-apoptotic cells as reported recently. Tissue microarrays (TMAs) consisting of tumour tissue from 93 stage II and III colon cancer patients were analysed by immunohistochemistry. Surprisingly, patients with low levels of active Caspase-3 had an increased disease-free survival time. This was particularly pronounced in patients who received 5FU-based adjuvant CT. In line with this observation, lower serum levels of active Caspase-3 were found in patients with metastasised CRC who revealed stable disease or tumour regression compared with those with disease progression. The role of Caspase-3 in treatment responses was explored further in primary human tumour explant cultures from fresh patient tumour tissue. Exposure of explant cultures to 5FU-based CT increased the percentage of cells positive for active Caspase-3 and Terminal Deoxynucleotidyl Transferase dUTP Nick end Labelling (TUNEL), but also the expression of regeneration and proliferation markers ß-Catenin and Ki-67, as well as cyclooxygenase-2 (COX-2). Of note, selective inhibition of Caspase-3 with Ac-DNLD-CHO, a selective, reversible inhibitor of Caspase-3, significantly reduced the expression of proliferation markers as well as COX-2. Inhibition of COX-2 with aspirin or celecoxib did not affect Caspase-3 levels but also reduced Ki-67 and ß-Catenin levels, suggesting that Caspase-3 acted via COX-2 to stimulate cell proliferation and tissue regeneration. This indicates that low levels of active Caspase-3 may represent a new predictor of CT responsiveness, and inhibition of Caspase-3, or antagonising downstream effectors of Caspase-3 paracrine signalling, such as COX-2 may improve patient outcomes following CT in advanced CRC.


Assuntos
Caspase 3/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/enzimologia , Fluoruracila/farmacologia , Antimetabólitos Antineoplásicos/farmacologia , Caspase 3/genética , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Análise Serial de Tecidos
12.
Science ; 350(6261): aad0210, 2015 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-26542576

RESUMO

Coupling between the lower and upper atmosphere, combined with loss of gas from the upper atmosphere to space, likely contributed to the thin, cold, dry atmosphere of modern Mars. To help understand ongoing ion loss to space, the Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft made comprehensive measurements of the Mars upper atmosphere, ionosphere, and interactions with the Sun and solar wind during an interplanetary coronal mass ejection impact in March 2015. Responses include changes in the bow shock and magnetosheath, formation of widespread diffuse aurora, and enhancement of pick-up ions. Observations and models both show an enhancement in escape rate of ions to space during the event. Ion loss during solar events early in Mars history may have been a major contributor to the long-term evolution of the Mars atmosphere.

13.
Science ; 350(6261): aad0459, 2015 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-26542579

RESUMO

The Mars Atmosphere and Volatile Evolution (MAVEN) mission, during the second of its Deep Dip campaigns, made comprehensive measurements of martian thermosphere and ionosphere composition, structure, and variability at altitudes down to ~130 kilometers in the subsolar region. This altitude range contains the diffusively separated upper atmosphere just above the well-mixed atmosphere, the layer of peak extreme ultraviolet heating and primary reservoir for atmospheric escape. In situ measurements of the upper atmosphere reveal previously unmeasured populations of neutral and charged particles, the homopause altitude at approximately 130 kilometers, and an unexpected level of variability both on an orbit-to-orbit basis and within individual orbits. These observations help constrain volatile escape processes controlled by thermosphere and ionosphere structure and variability.

14.
Eur J Clin Microbiol Infect Dis ; 31(11): 3163-71, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22752150

RESUMO

Asymptomatic Clostridium difficile carriage has a prevalence reported as high as 51-85 %; with up to 84 % of incident hospital-acquired infections linked to carriers. Accurately identifying carriers may limit the spread of Clostridium difficile. Since new technology adoption depends heavily on its economic value, we developed an analytic simulation model to determine the cost-effectiveness screening hospital admissions for Clostridium difficile from the hospital and third party payer perspectives. Isolation precautions were applied to patients testing positive, preventing transmission. Sensitivity analyses varied Clostridium difficile colonization rate, infection probability among secondary cases, contact isolation compliance, and screening cost. Screening was cost-effective (i.e., incremental cost-effectiveness ratio [ICER] ≤ $50,000/QALY) for every scenario tested; all ICER values were ≤ $256/QALY. Screening was economically dominant (i.e., saved costs and provided health benefits) with a ≥10.3 % colonization rate and ≥5.88 % infection probability when contact isolation compliance was ≥25 % (hospital perspective). Under some conditions screening led to cost savings per case averted (range, $53-272). Clostridium difficile screening, coupled with isolation precautions, may be a cost-effective intervention to hospitals and third party payers, based on prevalence. Limiting Clostridium difficile transmission can reduce the number of infections, thereby reducing its economic burden to the healthcare system.


Assuntos
Portador Sadio/diagnóstico , Clostridioides difficile/isolamento & purificação , Infecções por Clostridium/diagnóstico , Testes Diagnósticos de Rotina/economia , Testes Diagnósticos de Rotina/métodos , Programas de Rastreamento/economia , Programas de Rastreamento/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Custos e Análise de Custo , Feminino , Hospitais , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Adulto Jovem
15.
Phys Rev Lett ; 107(4): 041804, 2011 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-21866995

RESUMO

We report the observation of the decay B- → D(s)((*)+) K- ℓ- ν(ℓ) based on 342 fb(-1) of data collected at the Υ(4S) resonance with the BABAR detector at the PEP-II e+ e- storage rings at SLAC. A simultaneous fit to three D(s)(+) decay chains is performed to extract the signal yield from measurements of the squared missing mass in the B meson decay. We observe the decay B- → D(s)((*)+) K- ℓ- ν(ℓ) with a significance greater than 5 standard deviations (including systematic uncertainties) and measure its branching fraction to be B(B- → D(s)((*)+) K- ℓ- ν(ℓ)) = [6.13(-1.03)(+1.04)(stat)±0.43(syst)±0.51(B(D(s)))]×10(-4), where the last error reflects the limited knowledge of the D(s) branching fractions.

16.
Phys Rev Lett ; 107(2): 021804, 2011 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-21797597

RESUMO

We search for single-photon decays of the Υ(1S) resonance, Υ â†’ γ + invisible, where the invisible state is either a particle of definite mass, such as a light Higgs boson A°, or a pair of dark matter particles, χχ. Both A° and χ are assumed to have zero spin. We tag Υ(1S) decays with a dipion transition Υ(2S) → π⁺π⁻Υ(1S) and look for events with a single energetic photon and significant missing energy. We find no evidence for such processes in the mass range m(A°) ≤ 9.2 GeV and m(χ) ≤ 4.5 GeV in the sample of 98 × 106 Υ(2S) decays collected with the BABAR detector and set stringent limits on new physics models that contain light dark matter states.

17.
Phys Rev Lett ; 104(19): 191801, 2010 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-20866959

RESUMO

The ratio R(τµ)(Υ(1S))=Γ(Υ(1S)→τ+ τ-)/Γ(Υ(1S)→µ+ µ-) is measured using a sample of (121.8±1.2)×10(6)Υ(3S) events recorded by the BABAR detector. This measurement is intended as a test of lepton universality and as a search for a possible light pseudoscalar Higgs boson. In the standard model (SM) this ratio is expected to be close to 1. Any significant deviations would violate lepton universality and could be introduced by the coupling to a light pseudoscalar Higgs boson. The analysis studies the decays Υ(3S)→Υ(1S)π+ π-, Υ(1S)→l+ l-, where l=µ, τ. The result, R(τµ)(Υ(1S))=1.005±0.013(stat)±0.022(syst), shows no deviation from the expected SM value, while improving the precision with respect to previous measurements.

18.
Phys Rev Lett ; 105(12): 121801, 2010 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-20867628

RESUMO

We report the measurement of the Cabibbo-Kobayashi-Maskawa CP-violating angle γ through a Dalitz plot analysis of neutral D-meson decays to K(S)(0) π+ π- and K(S)(0) K+ K- produced in the processes B∓ → DK∓, B∓ D* K∓ with D* → Dπ(0), Dγ, and B∓ → DK*∓ with K*∓ → K(S)(0) π∓, using 468 million BB pairs collected by the BABAR detector at the PEP-II asymmetric-energy e+ e- collider at SLAC. We measure γ = (68 ± 14 ± 4 ± 3)° (modulo 180°), where the first error is statistical, the second is the experimental systematic uncertainty, and the third reflects the uncertainty in the description of the neutral D decay amplitudes. This result is inconsistent with γ = 0 (no direct CP violation) with a significance of 3.5 standard deviations.

19.
Phys Rev Lett ; 105(5): 051602, 2010 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-20867905

RESUMO

Using 467 fb(-1) of e+e- annihilation data collected with the BABAR detector, we measure (B(τ- → µ- ν(µ) ν(τ)))/(B(τ- → e- ν(e) ν(τ))) =(0.9796±0.0016±0.0036), (B(τ- → π- ν(τ)))/(B(τ- → e- ν(e) ν(τ))) = (0.5945±0.0014±0.0061), and (B(τ- → K- ν(τ)))/(B(τ- → e- ν(e) ν(τ))) = (0.03882±0.00032±0.00057), where the uncertainties are statistical and systematic, respectively. From these precision τ measurements, we test the standard model assumption of µ-e and τ-µ charge current lepton universality and provide determinations of |Vus| experimentally independent of the decay of a kaon.

20.
Phys Rev Lett ; 105(8): 081803, 2010 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-20868092

RESUMO

We report a direct measurement of D0-D0 mixing parameters through a time-dependent amplitude analysis of the Dalitz plots of D(0) → K(S)(0) π+ π- and, for the first time, D0 → K(S)(0)K+ K- decays. The low-momentum pion π(s)(+) in the decay D*+ → D0 π(s)(+) identifies the flavor of the neutral D meson at its production. Using 468.5 fb(-1) of e+ e- colliding-beam data recorded near square root(s)=10.6 GeV by the BABAR detector at the PEP-II asymmetric-energy collider at SLAC, we measure the mixing parameters x = [1.6 ± 2.3(stat) ± 1.2(syst) ± 0.8(model)] × 10(-3), and y = [5.7 ± 2.0(stat) ± 1.3(syst) ± 0.7(model)] × 10(-3). These results provide the best measurement to date of x and y. The knowledge of the value of x, in particular, is crucial for understanding the origin of mixing.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...