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1.
Rep Prog Phys ; 85(2)2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-34942603

RESUMO

In this paper, we describe the potential of the LHCb experiment to detect stealth physics. This refers to dynamics beyond the standard model that would elude searches that focus on energetic objects or precision measurements of known processes. Stealth signatures include long-lived particles and light resonances that are produced very rarely or together with overwhelming backgrounds. We will discuss why LHCb is equipped to discover this kind of physics at the Large Hadron Collider and provide examples of well-motivated theoretical models that can be probed with great detail at the experiment.

2.
J Dairy Sci ; 98(6): 3826-39, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25864049

RESUMO

With the objective to optimize fixed-time artificial insemination (FTAI) protocols based on estradiol benzoate (EB) and progesterone (P4), we performed 2 experiments (Exp.) in dairy cows. In Exp. 1 (n=44), we hypothesized that increased EB (EB3=3 mg vs. EB2=2 mg) on d 0 would improve synchronization of ovarian follicle wave emergence. Likewise, in Exp. 2 (n=82), we hypothesized that a GnRH treatment on d -3 (early in a follicular wave on d 0) versus d -7 (presence of a dominant follicle on d 0) would better synchronize wave emergence. Moreover, results from both experiments were combined to identify reasons for the lack of synchronization. All cows were treated with EB at the time of introduction of a P4 implant (d 0). On d 7, cows were given 25 mg of prostaglandin F2α; on d 8, the implant was removed and cows were given 1mg of estradiol cypionate. All cows received FTAI on d 10. In both experiments, daily ultrasound evaluations were performed and, in Exp. 2, circulating P4 was evaluated during the protocol. Pregnancy per artificial insemination (P/AI) was determined on d 31 and 59 after FTAI. In Exp. 1, EB dose did not change time to wave emergence, but EB3 compared with EB2 decreased the percentage of cows with a corpus luteum on d 7 (19.8 vs. 55.3%) and time to ovulation (10.4 vs. 10.9 d). In Exp. 2, although we detected a tendency for delayed follicle wave emergence after the start of the FTAI protocol in cows ovulating to GnRH given on d -7, there was no difference in percentage of cows with a synchronized wave emergence (~80%). Regardless of treatment, more cows with P4<0.1 ng/mL, compared with P4≥0.1 and <0.22 ng/mL at the time of AI, ovulated to the protocol (81.2 vs. 58.0%) and had increased P/AI (47.4 vs. 21.4%). An analysis of data from both experiments showed that only 73.8% (93/126) of cows had synchronized wave emergence, and only 77.8% (98/126) of cows ovulated at the end of the protocol. Fertility was much greater in cows that had emergence of a new wave synchronized and ovulated to end of the protocol [P/AI 61.3% (46/75)] compared with cows that failed to present one or both of the outcomes above [15.7% (8/51)]. Thus, although current FTAI protocols using EB and P4 produce P/AI between 30 and 40% for lactating dairy cows, there remains room for improvement because less than 60% (75/126) of the cows were correctly synchronized. Starting the FTAI protocol without the dominant follicle or increasing the dose of EB to 3mg was not effective in increasing synchronization rate.


Assuntos
Bovinos , Estradiol/análogos & derivados , Hormônio Liberador de Gonadotropina/administração & dosagem , Inseminação Artificial/veterinária , Animais , Corpo Lúteo/efeitos dos fármacos , Dinoprosta/administração & dosagem , Estradiol/administração & dosagem , Sincronização do Estro/métodos , Feminino , Fertilidade/efeitos dos fármacos , Inseminação Artificial/métodos , Lactação , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/fisiologia , Ovulação/efeitos dos fármacos , Indução da Ovulação/métodos , Indução da Ovulação/veterinária , Gravidez , Progesterona/administração & dosagem , Progesterona/sangue , Fatores de Tempo , Resultado do Tratamento
3.
Arch Oral Biol ; 127: 105148, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34022546

RESUMO

OBJECTIVE: The aim of this study was to synthesize and characterize an experimental primer containing cationic lipid nanoparticles (NPL-chitosan) and to evaluate its properties. DESIGN: The NPL-chitosan were synthesized by emulsion and sonication method. The experimental primers were applied in dentin surface of fifty human molars. The experimental groups were: 1) application of commercial primer; 2) Primer containing 2% of Chlorhexidine (CHX) 3); Primer with 2% NPL-chitosan 4); Primer with 0.6 % of NPL-chitosan 5); Primer with 0.4 % of NPL-chitosan. A composite resin plateau was used for the analysis, where sections were made for making the dentin beams. The effect of experimental primer with cationic nanoparticles in the inhibition of matrix metalloproteinase (MMP) activity was carrying out by in situ zymography. For the Resin-Dentin Adhesive Strength and in situ Zymography analysis, was used the One-way analysis of variance (ANOVA) with significance level of 95 %. RESULTS: Spherical NPL-chitosan presented size below 220 nm, polydispersity index of 0.179 and zeta potential positive and was stable over 75 days. These nanoparticles showed antibacterial activity agsainst S. mutans with MIC of the 0.4 % and MBC of 0.67 %. In the Microtensile Strength, no statistical difference was observed between the experimental groups (p = 0.9054). The in situ zymography assay showed that the group with 2% of NPL-chitosan presented higher inactivation activity of MMPs compared to the other groups (p < 0.05). CONCLUSION: The experimental primer containing NPL-chitosan has antimicrobial activity, does not alter the adhesive resistance and inactivates MMPs present in dentin.


Assuntos
Quitosana , Colagem Dentária , Nanopartículas , Resinas Compostas , Cimentos Dentários/farmacologia , Dentina , Adesivos Dentinários , Humanos , Teste de Materiais , Metaloproteases , Cimentos de Resina , Resistência à Tração
4.
Ann Oncol ; 21(12): 2333-2341, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20511340

RESUMO

BACKGROUND: The natural history and consequences of severe H1N1 influenza infection among cancer patients are not yet fully characterized. We describe eight cases of H1N1 infection in cancer patients admitted to the intensive care unit of a referral cancer center. PATIENTS AND METHODS: Clinical data from all patients admitted with acute respiratory failure due to novel viral H1N1 infection were reviewed. Lung tissue was submitted for viral and bacteriological analyses by real-time RT-PCR, and autopsy was conducted on all patients who died. RESULTS: Eight patients were admitted, with ages ranging from 55 to 65 years old. There were five patients with solid organ tumors (62.5%) and three with hematological malignancies (37.5%). Five patients required mechanical ventilation and all died. Four patients had bacterial bronchopneumonia. All deaths occurred due to multiple organ failure. A milder form of lung disease was present in the three cases who survived. Lung tissue analysis was performed in all patients and showed diffuse alveolar damage in most patients. Other lung findings were necrotizing bronchiolitis or extensive hemorrhage. CONCLUSIONS: H1N1 viral infection in patients with cancer can cause severe illness, resulting in acute respiratory distress syndrome and death. More data are needed to identify predictors of unfavorable evolution in these patients.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Influenza Humana/complicações , Neoplasias/complicações , Idoso , Autopsia , Feminino , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/fisiologia , Influenza Humana/diagnóstico por imagem , Influenza Humana/mortalidade , Influenza Humana/patologia , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/etiologia , Insuficiência de Múltiplos Órgãos/patologia , Neoplasias/diagnóstico por imagem , Neoplasias/mortalidade , Neoplasias/patologia , Radiografia , Respiração Artificial , Síndrome do Desconforto Respiratório/diagnóstico por imagem , Síndrome do Desconforto Respiratório/etiologia , Síndrome do Desconforto Respiratório/mortalidade , Síndrome do Desconforto Respiratório/patologia , Estudos Retrospectivos , Índice de Gravidade de Doença
5.
Eur Phys J C Part Fields ; 78(3): 256, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-31258409

RESUMO

We use MasterCode to perform a frequentist analysis of the constraints on a phenomenological MSSM model with 11 parameters, the pMSSM11, including constraints from ∼ 36 /fb of LHC data at 13 TeV and PICO, XENON1T and PandaX-II searches for dark matter scattering, as well as previous accelerator and astrophysical measurements, presenting fits both with and without the ( g - 2 ) µ constraint. The pMSSM11 is specified by the following parameters: 3 gaugino masses M 1 , 2 , 3 , a common mass for the first-and second-generation squarks m q ~ and a distinct third-generation squark mass m q ~ 3 , a common mass for the first-and second-generation sleptons m ℓ ~ and a distinct third-generation slepton mass m τ ~ , a common trilinear mixing parameter A, the Higgs mixing parameter µ , the pseudoscalar Higgs mass M A and tan ß . In the fit including ( g - 2 ) µ , a Bino-like χ ~ 1 0 is preferred, whereas a Higgsino-like χ ~ 1 0 is mildly favoured when the ( g - 2 ) µ constraint is dropped. We identify the mechanisms that operate in different regions of the pMSSM11 parameter space to bring the relic density of the lightest neutralino, χ ~ 1 0 , into the range indicated by cosmological data. In the fit including ( g - 2 ) µ , coannihilations with χ ~ 2 0 and the Wino-like χ ~ 1 ± or with nearly-degenerate first- and second-generation sleptons are active, whereas coannihilations with the χ ~ 2 0 and the Higgsino-like χ ~ 1 ± or with first- and second-generation squarks may be important when the ( g - 2 ) µ constraint is dropped. In the two cases, we present χ 2 functions in two-dimensional mass planes as well as their one-dimensional profile projections and best-fit spectra. Prospects remain for discovering strongly-interacting sparticles at the LHC, in both the scenarios with and without the ( g - 2 ) µ constraint, as well as for discovering electroweakly-interacting sparticles at a future linear e + e - collider such as the ILC or CLIC.

6.
Eur Phys J C Part Fields ; 77(2): 104, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28260982

RESUMO

We perform a likelihood analysis of the constraints from accelerator experiments and astrophysical observations on supersymmetric (SUSY) models with SU(5) boundary conditions on soft SUSY-breaking parameters at the GUT scale. The parameter space of the models studied has seven parameters: a universal gaugino mass [Formula: see text], distinct masses for the scalar partners of matter fermions in five- and ten-dimensional representations of SU(5), [Formula: see text] and [Formula: see text], and for the [Formula: see text] and [Formula: see text] Higgs representations [Formula: see text] and [Formula: see text], a universal trilinear soft SUSY-breaking parameter [Formula: see text], and the ratio of Higgs vevs [Formula: see text]. In addition to previous constraints from direct sparticle searches, low-energy and flavour observables, we incorporate constraints based on preliminary results from 13 TeV LHC searches for jets + [Formula: see text] events and long-lived particles, as well as the latest PandaX-II and LUX searches for direct Dark Matter detection. In addition to previously identified mechanisms for bringing the supersymmetric relic density into the range allowed by cosmology, we identify a novel [Formula: see text] coannihilation mechanism that appears in the supersymmetric SU(5) GUT model and discuss the role of [Formula: see text] coannihilation. We find complementarity between the prospects for direct Dark Matter detection and SUSY searches at the LHC.

7.
Eur Phys J C Part Fields ; 77(4): 268, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28515671

RESUMO

We perform a likelihood analysis of the minimal anomaly-mediated supersymmetry-breaking (mAMSB) model using constraints from cosmology and accelerator experiments. We find that either a wino-like or a Higgsino-like neutralino LSP, [Formula: see text], may provide the cold dark matter (DM), both with similar likelihoods. The upper limit on the DM density from Planck and other experiments enforces [Formula: see text] after the inclusion of Sommerfeld enhancement in its annihilations. If most of the cold DM density is provided by the [Formula: see text], the measured value of the Higgs mass favours a limited range of [Formula: see text] (and also for [Formula: see text] if [Formula: see text]) but the scalar mass [Formula: see text] is poorly constrained. In the wino-LSP case, [Formula: see text] is constrained to about [Formula: see text] and [Formula: see text] to [Formula: see text], whereas in the Higgsino-LSP case [Formula: see text] has just a lower limit [Formula: see text] ([Formula: see text]) and [Formula: see text] is constrained to [Formula: see text] in the [Formula: see text] ([Formula: see text]) scenario. In neither case can the anomalous magnetic moment of the muon, [Formula: see text], be improved significantly relative to its Standard Model (SM) value, nor do flavour measurements constrain the model significantly, and there are poor prospects for discovering supersymmetric particles at the LHC, though there are some prospects for direct DM detection. On the other hand, if the [Formula: see text] contributes only a fraction of the cold DM density, future LHC [Formula: see text]-based searches for gluinos, squarks and heavier chargino and neutralino states as well as disappearing track searches in the wino-like LSP region will be relevant, and interference effects enable [Formula: see text] to agree with the data better than in the SM in the case of wino-like DM with [Formula: see text].

8.
Phytochemistry ; 55(7): 809-13, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11190401

RESUMO

Lychnophora ericoides is a Brazilian medicinal plant that is commercially available as an analgesic and anti-inflammatory agent. The extract from roots, which yielded 10 lignans, showed analgesic activity in the mouse writhing test and the lignan, cubebin, was one of the most active. Anti-inflammatory and anti-pyretic activities from cubebin (10 mg/kg) revealed no significant effects. In addition two previously unknown methyl clusin derivatives are reported.


Assuntos
Analgésicos/farmacologia , Asteraceae/química , Lignanas/farmacologia , Animais , Lignanas/química , Lignanas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Raízes de Plantas/química , Ratos , Ratos Wistar , Espectrometria de Massas por Ionização por Electrospray
10.
Eur J Clin Pharmacol ; 33(5): 473-7, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3480806

RESUMO

The effects of nadolol on renal haemodynamics and function, and on the renin-angiotensin-aldosterone system and on renal prostaglandin production were studied in eighteen cirrhotics. After 1 month of treatment, nadolol had significantly decreased cardiac output by 25% without affecting arterial pressure, renal plasma flow or renal vascular resistance. Glomerular filtration rate, filtration fraction and the proportion of the cardiac output delivered to the kidneys were significantly increased. The renin-angiotensin-aldosterone system was suppressed and urinary PGE2 excretion was slightly increased. The latter effects were not correlated with those on renal haemodynamics and function.


Assuntos
Rim/efeitos dos fármacos , Cirrose Hepática/tratamento farmacológico , Nadolol/farmacologia , Sistema Renina-Angiotensina/efeitos dos fármacos , Débito Cardíaco/efeitos dos fármacos , Dinoprostona , Taxa de Filtração Glomerular/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Humanos , Rim/irrigação sanguínea , Prostaglandinas E/urina
11.
J Pediatr (Rio J) ; 76(6): 458-60, 2000.
Artigo em Português | MEDLINE | ID: mdl-14647635

RESUMO

PURPOSE: Transient aplastic crisis is reported in an eight-month old child with sickle cell anemia and acute B19 parvovirus infection. This fact is uncommon in this age. PATIENT AND METHODS: The authors review the literature and describe a clinical case of an eight-month old child with sickle cell anemia presented with profound anemia and reticulocytopenia. His peripheral blood was analyzed for parvovirus B19 using the polymerase chain reaction (PCR), and for anti B19 immunoglobulin Ig M, and Ig G by enzyme-linked immunosorbent assay (ELISA). RESULTS: An eight-month old child with sickle cell anemia was admitted to the hospital with fever and profound anemia (HB = 3.8g/ dl) and reticulocytopenia (2%). A diagnosis of aplastic crisis was established. The results indicate that Ig M and PCR were positive and Ig G negative. The patient needed erytrocyte transfusion, and was discharged on hospital day 4. CONCLUSIONS: The clinical and laboratory features indicate that human parvovirus B19 was the etiologic agent of an aplastic crisis in an eight-month old child. According to the international literature this event is uncommon for this age; in addition, this is the first time it appears in the Brazilian literature.

12.
Nephron ; 59(3): 477-81, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1758541

RESUMO

Defibrotide (DF) has been proposed as a new antithrombotic agent in renal transplantation. Because it was also found to increase prostacyclin synthesis, a reduction in ciclosporin (CS) nephrotoxicity could be supposed. To ascertain this hypothesis, renal function and urinary prostanoids were evaluated in four groups of rats after 10 days of oral treatment (doses in mg/kg/day): CS 50 (group A), CS 50 + DF 400 (group B), DF 400 (group C) and controls (group D). Compared to controls, creatinine clearance (CCR) was significantly lower in groups A and B (In CCr: A = 6.62 +/- 0.28, B = 6.83 +/- 0.24 vs. 8.17 +/- 0.13 microliters/min, p less than 0.01), whereas it did not change in group C (8.03 +/- 0.24 microliters/min). The urinary excretion of prostaglandin E2 (PGE2) was significantly (p less than 0.05) higher in group A (In PGE2: 3.98 +/- 0.98 nmol/mol Cr) and more evidently in groups B and C (6.89 +/- 0.38 and 6.01 +/- 0.32 nmol/mol Cr, respectively) compared to controls (1.43 +/- 0.45 nmol/mol Cr). The urinary excretion of 6-keto-PGF1 alpha and of thromboxane B2 (TxB2) were higher only in groups A and B (ln 6-keto-PGF1 alpha and ln TxB2: A = 6.45 +/- 0.22 and 4.97 +/- 0.20, B = 7.06 +/- 0.31 and 5.43 +/- 0.41 vs. group D = 5.53 +/- 0.22 and 3.79 +/- 0.42 nmol/mol Cr; p less than 0.05). The 6-keto-PGF1 alpha/Tx molar ratio was not significantly affected, although a trend for a reduction in the ratio was found in the treated rats.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Ciclosporina/antagonistas & inibidores , Rim/efeitos dos fármacos , Polidesoxirribonucleotídeos/farmacologia , Prostaglandinas/urina , Animais , Ciclosporina/toxicidade , Fibrinolíticos/farmacologia , Rim/fisiologia , Transplante de Rim , Masculino , Ratos , Ratos Endogâmicos
13.
Kidney Int ; 38(1): 136-44, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2166857

RESUMO

Renal and hormonal responses were studied in a group of healthy individuals fed, in random order, for three weeks, a vegetable protein diet (N = 10), an animal protein diet (N = 10), or an animal protein diet supplemented with fiber (N = 7), all containing the same amount of total protein (chronic study). In seven additional subjects the acute renal, metabolic and hormonal response to ingestion of a meat or soya load of equivalent total protein content was investigated (acute study). In the chronic study GRF, RPF and fractional clearance of albumin and IgG were significantly higher on the animal than the vegetable protein diets (GFR: 121 +/- 4 vs. 111 +/- 4 ml/min/1.73 m2, P less than 0.001; RPF: 634 +/- 29 vs. 559 +/- 26 ml/min/1.73 m2, P less than 0.001; theta alb: 19.5 +/- 3.1 vs. 10.2 +/- 1.6 x 10(-7), P less than 0.01; theta IgG: 11.6 +/- 3.1 vs. 7.5 +/- 1.7 x 10(-7), P less than 0.05). Renal vascular resistance was lower on the animal than vegetable protein diet (82 +/- 5 vs. 97 +/- 5 mmHg/min/liter; P less than 0.001). Fiber supplementation to APD did not have any effect on the renal variables measured which were indistinguishable from APD. In the acute study, GFR and RPF both rose significantly by approximately 16% (P less than 0.005) and approximately 14% (P less than 0.05), respectively, after the meat load, while RVR fell by approximately 12% (P less than 0.05). There were no significant changes in these parameters following the soya load.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Aminoácidos/metabolismo , Proteínas Alimentares/farmacologia , Glucagon/metabolismo , Rim/fisiologia , Carne , Proteínas de Vegetais Comestíveis/farmacologia , Prostaglandinas/metabolismo , Adulto , Fibras na Dieta/farmacologia , Taxa de Filtração Glomerular , Humanos , Masculino , Circulação Renal/fisiologia
14.
Am J Physiol ; 258(3 Pt 2): F675-83, 1990 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2316671

RESUMO

The renal response to 100 g/1.73 m2 protein load in the form of a meat meal was studied in 19 normal subjects and 35 normoalbuminuric insulin-dependent diabetic patients (IDDs) under conditions of sustained euglycemia. The area under the glomerular filtration rate (GFR) curve rose above base line by 1,904 +/- 292 in normals and 502 +/- 237 ml/1.73 m2 in IDDs (P less than 0.01). The meat meal induced a greater increment in the area under the glucagon curve in normals (14,930 +/- 186 pg.ml-1.min-1) than in IDDs (7,227 +/- 67, P less than 0.01); similarly urinary excretion of prostaglandin E2 and 6-ketoprostaglandin F1 alpha rose by 119 and 98%, respectively, in normals but only by 2% (P less than 0.01 vs. normals) and 10% (P less than 0.01 vs. normals) in IDDs. The fractional albumin clearance rose by 102 and 251% in normals and IDDs, respectively. In five normal subjects indomethacin administration abolished the GFR, glucagon, prostaglandin, and albuminuric response to meat ingestion. Glucagon replacement under indomethacin treatment failed to restore these responses. In five diabetic patients, selected for having a flat glucagon and GFR response to a meat meal, replacement of glucagon to postprandial levels increased urinary vasodilatory prostaglandins and restored a normal GFR response. Thus in normal subjects renal vasodilatory prostaglandins appear to be the final effector of the renal hemodynamic and albuminuric response to a meat meal. The prostaglandin increase is likely to be mediated under physiological conditions by a glucagon rise, which, however, has no effect per se on renal hemodynamics.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Diabetes Mellitus Tipo 1/fisiopatologia , Ingestão de Alimentos , Glucagon/fisiologia , Rim/fisiopatologia , Carne , Prostaglandinas/fisiologia , Adulto , Diabetes Mellitus Tipo 1/metabolismo , Proteínas Alimentares/farmacologia , Feminino , Glucagon/farmacologia , Hemodinâmica , Hormônios/metabolismo , Humanos , Indometacina/farmacologia , Rim/metabolismo , Masculino , Prostaglandinas/urina , Proteinúria/urina , Sódio/metabolismo
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