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1.
Nature ; 539(7627): 69-71, 2016 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-27808190

RESUMO

Unlike the electroweak sector of the standard model of particle physics, quantum chromodynamics (QCD) is surprisingly symmetric under time reversal. As there is no obvious reason for QCD being so symmetric, this phenomenon poses a theoretical problem, often referred to as the strong CP problem. The most attractive solution for this requires the existence of a new particle, the axion-a promising dark-matter candidate. Here we determine the axion mass using lattice QCD, assuming that these particles are the dominant component of dark matter. The key quantities of the calculation are the equation of state of the Universe and the temperature dependence of the topological susceptibility of QCD, a quantity that is notoriously difficult to calculate, especially in the most relevant high-temperature region (up to several gigaelectronvolts). But by splitting the vacuum into different sectors and re-defining the fermionic determinants, its controlled calculation becomes feasible. Thus, our twofold prediction helps most cosmological calculations to describe the evolution of the early Universe by using the equation of state, and may be decisive for guiding experiments looking for dark-matter axions. In the next couple of years, it should be possible to confirm or rule out post-inflation axions experimentally, depending on whether the axion mass is found to be as predicted here. Alternatively, in a pre-inflation scenario, our calculation determines the universal axionic angle that corresponds to the initial condition of our Universe.

2.
Phys Rev Lett ; 127(23): 232002, 2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34936768

RESUMO

We discuss spontaneously broken quantum field theories with a continuous global symmetry group via the constraint effective potential. Employing lattice simulations with constrained values of the order parameter, we demonstrate explicitly that the path integral is dominated by inhomogeneous field configurations and that these are unambiguously related to the flatness of the effective potential in the broken phase. We determine characteristic features of these inhomogeneities, including their topology and the scaling of the associated excess energy with their size. Concerning the latter we introduce the differential surface tension-the generalization of the concept of a surface tension pertaining to discrete symmetries. Within our approach, spontaneous symmetry breaking is captured merely via the existence of inhomogeneities, i.e., without the inclusion of an explicit breaking parameter and a careful double limiting procedure to define the order parameter. While here we consider the three-dimensional O(2) model, we also elaborate on possible implications of our findings for the chiral limit of QCD.

3.
Dig Dis Sci ; 66(10): 3495-3504, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33128681

RESUMO

BACKGROUND: Dieulafoy's lesion (DL) is a rare but increasingly recognized cause of severe upper GI hemorrhage (SUGIH). There is little consensus regarding the endoscopic approach to management of bleeding from DL. AIMS: Our purposes were to compare 30-day outcomes of patients with SUGIH from DL with Doppler endoscopic probe (DEP) monitoring of blood flow and guided treatment versus standard visually guided hemostasis (VG). METHODS: Eighty-two consecutive DL patients with SUGIH were identified in a large CURE Hemostasis database from previous prospective cohort studies and two recent RCTs at two university-based medical centers. 30-day outcomes including rebleeding, surgery, angiography, death, and severe medical complications were compared between the two treatment groups. RESULTS: 40.2% of DL bleeds occurred in inpatients. 43.9% of patients had cardiovascular disease, and 48.7% were taking medications associated with bleeding. For the entire cohort, 41.3% (26/63) of patients treated with VG had a composite 30-day outcome as compared to 10.5% (2/19) of patients treated with DEP (p = 0.017). Rebleeding occurred within 30 days in 33.3% and 10.5% of those treated with VG and DEP, respectively (p = 0.051). After propensity score matching, the adjusted 30-day composite outcome occurred in 39.0% in the VG group compared to 2.6% in the DEP group (p < 0.001). Adjusted 30-day rebleeding occurred in 25.3% in the VG group versus 2.6% in the DEP group (p < 0.001). DISCUSSION: DL patients with SUGIH were frequently inpatients and had severe cardiovascular comorbidities and recurrent bleeding. Lesion arterial blood flow monitoring and obliteration are an effective way to treat bleeding from DL which reduces negative 30-day clinical outcomes.


Assuntos
Pressão Arterial , Artérias/anormalidades , Hemorragia Gastrointestinal/etiologia , Trato Gastrointestinal/irrigação sanguínea , Adulto , Idoso , Idoso de 80 Anos ou mais , Endoscopia do Sistema Digestório , Feminino , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Resultado do Tratamento , Adulto Jovem
4.
Br J Surg ; 103(3): 170-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26661686

RESUMO

BACKGROUND: Axillary reverse mapping (ARM) assesses the lymphatic drainage of the arm simultaneously with that of the breast, enabling preservation of arm lymphatics during axillary surgery for breast cancer. This article systematically reviews the evidence on the lymphoedema rate and oncological safety of the ARM technique. METHODS: PubMed, Embase and the Cochrane Library were searched systematically for studies that addressed the use of ARM during axillary surgery in breast cancer. Studies were eligible if they performed ARM during sentinel node biopsy (SNB) or axillary node clearance (ANC) for breast cancer in prospective studies of more than 50 patients, with assessment of lymphoedema and oncological outcomes during a minimum follow-up of 6 months. RESULTS: Eight studies reported data on ARM in 1142 patients undergoing axillary surgery for breast cancer. Lymphoedema rates ranged from 0 to 6 per cent during ARM-assisted SNB, and from 5.9 to 24 per cent during ARM lymphatic preservation at ANC. Crossover nodes between the arm and breast lymphatics were identified in 0-10 per cent of patients, and metastases were present in 0-20 per cent of these patients. ARM nodes were not preserved in between 11 and 18 per cent of patients with ARM nodes identified, and metastases were detected in 0-19 per cent of these patients. CONCLUSION: ARM can achieve low rates of lymphoedema, but the risk of metastasis in crossover and clinically suspicious ARM nodes, or those in close proximity to an involved sentinel node, warrants their excision.


Assuntos
Neoplasias da Mama/diagnóstico , Linfonodos/patologia , Estadiamento de Neoplasias , Biópsia de Linfonodo Sentinela/métodos , Axila , Feminino , Humanos , Metástase Linfática , Prognóstico
5.
Horm Metab Res ; 46(11): 749-52, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25208272

RESUMO

Previous studies have shown that in diabetes mellitus, insulin-induced relaxation of arteries is impaired and the level of ortho-tyrosine (o-Tyr), an oxidized amino acid is increased. Thus, we hypothesized that elevated vascular level of o-Tyr contributes to the impairment of insulin-induced vascular relaxation. Rats were fed with o-Tyr for 4 weeks. Insulin-induced vasomotor responses of isolated femoral artery were studied using wire myography. Vascular o-Tyr content was measured by HPLC, whereas immunoblot analyses were preformed to detect eNOS phosphorylation. Sustained oral supplementation of rats with o-Tyr increased the content of o-Tyr in the arterial wall and significantly reduced the relaxations to insulin. Sustained supplementation of cultured endothelial cells with o-Tyr increased the incorporation of o-Tyr and mitigated eNOS Ser (1 177) phosphorylation to insulin. Increasing arterial wall o-Tyr level attenuates insulin-induced relaxation - at least in part - by decreasing eNOS activation. Elevated level of o-Tyr could be an underlying mechanism for vasomotor dysfunction in diabetes mellitus.


Assuntos
Endotélio Vascular/metabolismo , Artéria Femoral/fisiologia , Insulina/farmacologia , Tirosina/metabolismo , Vasodilatação/efeitos dos fármacos , Administração Oral , Animais , Células Cultivadas , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Endotélio Vascular/efeitos dos fármacos , Artéria Femoral/efeitos dos fármacos , Técnicas In Vitro , Masculino , Camundongos , Óxido Nítrico Sintase Tipo III/metabolismo , Fosforilação/efeitos dos fármacos , Ratos Sprague-Dawley
6.
Endoscopy ; 45(5): 397-400, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23616128

RESUMO

We report a case series of all consecutive patients hospitalized in our two tertiary referral medical centers over the past 17 years for Cameron ulcers causing severe upper gastrointestinal hemorrhage (GIH) or severe obscure GIH. Cameron ulcers were diagnosed in 25 of the 3960 screened patients with severe upper GIH or severe obscure GIH (0.6 %). Of these, 21 patients had a prospective follow-up (median time 20.4 months [interquartile range: 8.5 - 31.8]). Patients were more often elderly women with chronic anemia, always had large hiatal hernias, and were usually referred for obscure GIH. Twelve of the 21 patients (57 %) were referred for surgery while being treated with high-dose proton pump inhibitors (PPIs). The other 9 patients (43 %) continued PPIs without any rebleeding during the follow-up. Cameron ulcers in large hiatal hernias are an uncommon cause of severe upper GIH. The choice of medical vs. surgical therapy should be individualized.


Assuntos
Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/terapia , Hérnia Hiatal/complicações , Hérnia Hiatal/terapia , Úlcera Gástrica/complicações , Úlcera Gástrica/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anemia/tratamento farmacológico , Anemia/etiologia , Feminino , Fundoplicatura , Gastropexia , Gastroscopia , Humanos , Análise de Intenção de Tratamento , Ferro/uso terapêutico , Masculino , Pessoa de Meia-Idade , Inibidores da Bomba de Prótons/uso terapêutico , Recidiva
7.
J Radiol Prot ; 33(1): 81-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23295854

RESUMO

One of the largest biomonitoring tasks is the assessing and environment monitoring of radiological wastes produced by mining. Po-210 and Pb-210 are easy to mobilise even in a weak acidic medium and as we know the biological behaviour and accumulation capacity of tobacco, this could be a suitable option for biomonitoring. During our work the Pb-210 and Po-210 concentration values of tobacco parts and soil samples originating from a Hungarian remediated uranium mine site were determined. The source preparation was spontaneous deposition following combined acidic leaching with a Po-209 tracer; the detection was carried out with a semiconductor ('PIPS') detector alpha-spectrometer. According to the results for the tobacco plant parts and soil samples, secular equilibrium could be found between the Pb-210 and Po-210 isotopes, and the isotope content of the lower leaves of the tobacco plants was in correlation with the isotope concentration of the soil; therefore, the measurement of the activity concentration is suitable for tracing smaller levels of washing out. The Po-210 activity concentration values of tobacco (average: 15.5 ± 3.6 Bq kg(-1)) and soil (average: 60.1 ± 15.2 Bq kg(-1)) samples originating from the area investigated compared with samples from another part of Hungary, Balatonalmádi (tobacco: 12.5 ± 1.0 Bq kg(-1), soil: 57.0 ± 4.7 Bq kg(-1)), do not show significant radionuclide migration.


Assuntos
Bioensaio/métodos , Radioisótopos de Chumbo/farmacocinética , Nicotiana/metabolismo , Folhas de Planta/metabolismo , Polônio/farmacocinética , Monitoramento de Radiação/métodos , Poluentes Radioativos do Solo/farmacocinética , Radioisótopos de Chumbo/análise , Polônio/análise , Poluentes Radioativos do Solo/análise
8.
Eur J Neurol ; 19(1): 15-20, e1-3, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21631649

RESUMO

Miller Fisher syndrome (MFS), a variant of the Guillain-Barré syndrome (GBS), is characterized by ophthalmoplegia, ataxia, and areflexia. The annual incidence is around one patient per one million population. The antiganglioside anti-GQ1b IgG antibody has a role in the pathogenesis of the syndrome, especially of ophthalmoplegia. The presence of this antibody in the serum can be identified in over 80% of the patients, peaking in the first week, whereas albuminocytological dissociation in the cerebrospinal fluid (CSF) appears later. The most consistent electrophysiological findings in MFS are reduced sensory nerve action potentials and absent H reflexes. More variability is seen with F waves and various investigations involving cranial structures. Although there are usually no abnormalities in MFS by routine neuroimaging, in a few cases, contrast enhancement of nerve roots and signs of central nervous system involvement were described supporting the hypothesis of an anti-GQ1b-syndrome, a continuum involving GBS, MFS, and Bickerstaff's brainstem encephalitis. Owing to the lack of randomized trials, treatments used for GBS (intravenous immunoglobulin and plasmapheresis) are usually applied, although from retrospective analyses, the outcome was similar between treated and untreated subjects. The outcome of MFS is usually good with case fatality of < 5%. In the few autopsy cases, macroscopic abnormalities were generally not seen in the nervous system. Microscopic examination of the peripheral nervous system (including cranial nerves) showed segmental demyelination with minimal perivascular infiltration with normal spinal cord and brain stem.


Assuntos
Síndrome de Miller Fisher/diagnóstico , Síndrome de Miller Fisher/imunologia , Síndrome de Miller Fisher/fisiopatologia , Humanos
9.
Appl Radiat Isot ; 181: 110073, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34971924

RESUMO

Safe, effective, cost-effective, easy feasible and low-waste decontamination technologies are fundamental importance from environmental and radiation protection aspects. In this study the effectiveness of AP-CITROX decontamination technology of Inconel alloy 690 was investigated. Non-radioactive representative metal samples were formed to test of decontamination technology and the clear-, the corroded-, the decontaminated layer were analysed electrochemically. The results indicate that the passivation step of the technology was not completed.


Assuntos
Ligas , Cromo , Descontaminação/métodos , Níquel , Humanos , Análise Espectral
10.
Appl Radiat Isot ; 170: 109594, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33476942

RESUMO

Although chloride compounds are the main cause of corrosion damage in distillation unit, standard methods to determine them do not guarantee good results. In this study, the chloride concentration of different crude oils was measured using different techniques and the results were compared. ASTM D3230, D4929 as standard methods, XRF as alternative technique and Neutron Activation Analysis as reference method, were applied. It is concluded that XRF method is an effective technique for measuring the chloride concentration of oils.

11.
J Environ Radioact ; 228: 106510, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33341753

RESUMO

Thoron (220Rn) exhalation from building materials has become increasingly recognized as a potential source for radiation exposure in dwellings. However, contrary to radon (222Rn), limited information on thoron exposure is available. As a result no harmonized test procedures for determining thoron exhalation from building materials are available at present. This study is a first interlaboratory comparison of different test methods to determine the thoron exhalation and a pre-step to a harmonized standard. The purpose of this study is to compare the experimental findings from a set of three building materials that are tested, and to identify future challenges in the development of a harmonized standard.


Assuntos
Poluentes Radioativos do Ar , Materiais de Construção , Monitoramento de Radiação , Radônio , Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Expiração , Habitação , Radônio/análise
12.
J Environ Radioact ; 229-230: 106543, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33515923

RESUMO

Data, despite being crucial for internal dose assessment, is lacking on the transfer of artificial radionuclides from the environment to the food supply. Expanding the available information on these factors is important for the improvement of dose models for specific scenarios. This paper describes the results of a 70 day field experiment with broiler chickens on the dynamics of excretion of 137Cs and 241Am from the muscle, liver and bone of broilers after a 30 day application of contaminated feed. The radionuclide concentrations in the feed and the thigh muscle, thigh bone and liver of 54 chickens divided between grass meal and soil contaminated feed groups were evaluated by gamma spectrometry for 241Am and 137Cs. The obtained results confirm previous data on the dynamics of the excretion of cesium from organs, which can be described with a fast and a slow exponential curve of excretion. On the 70th day, following the 30-days application, 2-8% of the first-day activity concentrations of 137Cs in organs (muscle, liver, bone) were detected. In the first two days, activity concentration of 241Am decreases twofold in both liver and bone. 35% of the maximum activity concentration of 241Am remained in bone and 15% in liver on the last day of the experiment.


Assuntos
Monitoramento de Radiação , Poluentes Radioativos do Solo , Ração Animal/análise , Animais , Radioisótopos de Césio/análise , Galinhas , Poluentes Radioativos do Solo/análise
13.
J Chem Phys ; 132(2): 024302, 2010 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-20095669

RESUMO

Collisional quenching of electronically excited states by inert gases is a fundamental physical process. For reactive excited species such as singlet methylene, (1)CH(2), the competition between relaxation and reaction has important implications in practical systems such as combustion. The gateway model has previously been applied to the relaxation of (1)CH(2) by inert gases [U. Bley and F. Temps, J. Chem. Phys. 98, 1058 (1993)]. In this model, gateway states with mixed singlet and triplet character allow conversion between the two electronic states. The gateway model makes very specific predictions about the relative relaxation rates of ortho and para quantum states of methylene at low temperatures; relaxation from para gateway states leads to faster deactivation independent of the nature of the collision partner. Experimental data are reported here which for the first time confirm these predictions at low temperatures for helium. However, it was found that in contrast with the model predictions, the magnitude of the effect decreases with increasing size of the collision partner. It is proposed that the attractive potential energy surface for larger colliders allows alternative gateway states to contribute to relaxation removing the dominance of the para gateway states.

14.
J R Soc Interface ; 17(173): 20200648, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33292097

RESUMO

Standard epidemic models based on compartmental differential equations are investigated under continuous parameter change as external forcing. We show that seasonal modulation of the contact parameter superimposed upon a monotonic decay needs a different description from that of the standard chaotic dynamics. The concept of snapshot attractors and their natural distribution has been adopted from the field of the latest climate change research. This shows the importance of the finite-time chaotic effect and ensemble interpretation while investigating the spread of a disease. By defining statistical measures over the ensemble, we can interpret the internal variability of the epidemic as the onset of complex dynamics-even for those values of contact parameters where originally regular behaviour is expected. We argue that anomalous outbreaks of the infectious class cannot die out until transient chaos is presented in the system. Nevertheless, this fact becomes apparent by using an ensemble approach rather than a single trajectory representation. These findings are applicable generally in explicitly time-dependent epidemic systems regardless of parameter values and time scales.


Assuntos
Doenças Transmissíveis , Epidemias , Doenças Transmissíveis/epidemiologia , Surtos de Doenças , Humanos , Dinâmica não Linear
15.
Phys Rev E ; 102(4-1): 042202, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33212712

RESUMO

We study the connection between transport phenomenon and escape rate statistics in two-dimensional standard map. For the purpose of having an open phase space, we let the momentum coordinate vary freely and restrict only angle with periodic boundary condition. We also define a pair of artificial holes placed symmetrically along the momentum axis where the particles might leave the system. As a consequence of the leaks the diffusion can be analyzed making use of only the ensemble of survived particles. We present how the diffusion coefficient depends on the size and position of the escape regions. Since the accelerator modes and, thus, the diffusion are strongly related to the system's control parameter, we also investigate effects of the perturbation strength. Numerical simulations show that the short-time escape statistics do not follow the well-known exponential decay especially for large values of perturbation parameters. The analysis of the escape direction also supports this picture as a significant amount of particles skip the leaks and leave the system just after a longtime excursion in the remote zones of the phase space.

16.
Eur J Surg Oncol ; 46(4 Pt A): 522-526, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31740186

RESUMO

INTRODUCTION: Determining the extent of residual disease in the breast and axilla following neoadjuvant chemotherapy (NACT) is vital for surgical planning. Traditionally patients with incomplete radiological response in the breast after NACT undergo axillary node clearance, regardless of axillary clinical and radiological response. The aim of this study was to determine whether radiological and/or pathological response in the breast to NACT were predictive of axillary response. MATERIALS AND METHODS: A retrospective cohort study of patients with operable breast cancer with histologically proven axillary lymph node involvement who received NACT and underwent definitive surgical treatment between 1/1/2016 and 31/12/2018 were included. All had MRI and/or US of the breast and axilla before, mid-treatment and at the end of NACT. RESULTS: The 83 patients had a median age of 50 years (range 25-77). MRI had a positive predictive value (PPV) of 52.6% and negative predictive value (NPV) of 81.8% for breast pathological complete response (pCR). For axillary pCR, US had a PPV of 60.0% and NPV of 89.6%. Only 71% of patients had radiological concordance; 15.9% had radiological complete response (rCR) in breast and axilla whilst 55.1% had neither breast nor axillary rCR. 85.6% of patients had pathological concordance (20.5% with breast and axillary pCR: 65.1% with residual disease in both). CONCLUSION: Radiological and pathological response in the breast to NACT does not accurately predict axillary response. The axilla and the breast should be viewed and assessed as two separate entities for treatment plans.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Linfonodos/diagnóstico por imagem , Adulto , Idoso , Axila , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Feminino , Humanos , Excisão de Linfonodo , Linfonodos/patologia , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Terapia Neoadjuvante , Neoplasia Residual , Valor Preditivo dos Testes , Estudos Retrospectivos , Biópsia de Linfonodo Sentinela , Resultado do Tratamento , Ultrassonografia
17.
PLoS One ; 15(7): e0235109, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32609724

RESUMO

Data on the transfer of artificial radionuclides from the environment to the food supply is necessary for internal dose assessment. There is a necessity for expanding and improving the available information on these factors in order to make better dose models for specific scenarios. This paper describes the results of a field experiment with broiler chickens on the transfer factor (Ff) and concentration ratio (CR) for the long-term intake of 241Am and 137Cs with grass meal and soil. The broilers were divided into two groups, each group had nine subgroups and each subgroup had three broilers. The radionuclide concentrations in the feed and the thigh muscle, thigh bone, and liver of 54 broilers divided between the grass meal and soil groups were evaluated by gamma spectrometry for 241Am and 137Cs. The duration of feeding with "contaminated" sources ranged between 1-70 days. The equilibrium stage of 241Am in muscle and bone occurs on the 1st and 40th day, respectively; for 137Cs in muscle- 30th days of intake and for liver and bone- 7th days. For 241Am, the liver did not reach equilibrium stage during the 70 days of intake. Ff of 137Cs in the "forage-muscle" and "soil-muscle" systems were determined as 1.9±0.3 and 0.18±0.05; Ff of 241Am in the "soil-muscle" system was-7.5×10-5.


Assuntos
Amerício/análise , Radioisótopos de Césio/análise , Galinhas , Contaminação Radioativa de Alimentos/análise , Aves Domésticas , Poluentes Radioativos do Solo/análise , Amerício/metabolismo , Ração Animal/análise , Animais , Radioisótopos de Césio/metabolismo , Galinhas/metabolismo , Abastecimento de Alimentos , Aves Domésticas/metabolismo , Poluentes Radioativos do Solo/metabolismo
18.
Physiol Int ; 107(2): 349-358, 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-32692716

RESUMO

Breast cancer is characterized by oncobiosis, the abnormal composition of the microbiome in neoplastic diseases. The biosynthetic capacity of the oncobiotic flora in breast cancer is suppressed, as suggested by metagenomic studies. The microbiome synthesizes a set of cytostatic and antimetastatic metabolites that are downregulated in breast cancer, including cadaverine, a microbiome metabolite with cytostatic properties. We set out to assess how the protein expression of constitutive lysine decarboxylase (LdcC), a key enzyme for cadaverine production, changes in the feces of human breast cancer patients (n = 35). We found that the fecal expression of Escherichia coli LdcC is downregulated in lobular cases as compared to invasive carcinoma of no special type (NST) cases. Lobular breast carcinoma is characterized by low or absent expression of E-cadherin. Fecal E. coli LdcC protein expression is downregulated in E-cadherin negative breast cancer cases as compared to positive ones. Receiver operating characteristic (ROC) analysis of LdcC expression in lobular and NST cases revealed that fecal E. coli LdcC protein expression might have predictive values. These data suggest that the oncobiotic transformation of the microbiome indeed leads to the downregulation of the production of cytostatic and antimetastatic metabolites. In E-cadherin negative lobular carcinoma that has a higher potential for metastasis formation, the protein levels of enzymes producing antimetastatic metabolites are downregulated. This finding represents a new route that renders lobular cases permissive for metastasis formation. Furthermore, our findings underline the role of oncobiosis in regulating metastasis formation in breast cancer.

19.
J Environ Radioact ; 222: 106322, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32565415

RESUMO

Horses are important food sources in several countries however, data on their radionuclide uptake is less available than for many other farm animals. Information on the transfer of artificial radioisotopes from the environment to the food supply is necessary for internal dose assessment and assuring the safety of the population relying on this food source. This study provides data for a less studied farm animal and, in the case of 241Am and 239+240Pu, relatively poorly studied radionuclides with respect to transfer to animal products. The transfer parameters for 239+240Pu, 241Am, 137Cs and 90Sr to the organs of 1-year old fillies, 10-year old mares and through the placental barrier into foetuses were quantified after 60-days feeding with contaminated soil or diet contaminated by a leachate solution. The transfer of radionuclides from ingested soil to tissues was generally lower, by up to three orders of magnitude, than from a diet contaminated by a leachate solution. The ingestion of soil is a particularly important source of radionuclide intake to grazing animals in the Semipalatinsk Test Site. For 241Am there is a lack of available data, the two singular entries for mutton and beef in the IAEA handbook are higher than all values observed in the current study. The maximum observed transfer factor for 241Am was 72 ± 22*10-5 d kg-1 FW in the liver of the mare fed with leachate contaminated feed. For 239+240Pu the maximum transfer factor was 31.8 ± 8*10-5 d kg-1 FW observed also in the liver of the mare fed with leachate contaminated feed. The filly fed with leachate contaminated feed had the highest transfer parameter value for 137Cs, 35.3*10-3 d kg-1 FW. The highest 90Sr transfer factor was found in the ribs of the filly fed leachate contaminated feed, 720 ± 144 *10-3 d kg-1 FW. The results presented in this paper can be used to improve the current internal dose estimates from the ingestion of horse meat produced in the area, however they are based on a low sample size; future studies need to use a larger number of animals.


Assuntos
Radioisótopos de Césio , Cavalos , Monitoramento de Radiação , Poluentes Radioativos do Solo , Radioisótopos de Estrôncio , Animais , Bovinos , Radioisótopos de Césio/farmacocinética , Feminino , Gravidez , Poluentes Radioativos do Solo/farmacocinética , Radioisótopos de Estrôncio/farmacocinética
20.
Scand J Immunol ; 69(5): 387-400, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19508370

RESUMO

The development of B-cell lymphomas is an intricate interplay among various pathogenic factors, leading to a multi-step process, encompassing various stages of B-cell maturation. Besides genetic abnormalities, a variety of environmental and microbial factors, as well as disproportional immune-regulatory processes lead to the malignant transformation. Yet, little is known about the exact chain of events, which lead from the physiological polyclonal B-cell activation as a response to exogenous antigens through oligoclonality to a monoclonal, uncontrolled, malignant B-cell proliferation. The aim of the present review was to summarize the potential harmful steps in the development of B-cell lymphomas, according to conventional and novel theories, and to depict therapeutic regimens presently in use as well as to envision future drug developments, beneficial in the battle against this lymphoid malignancy.


Assuntos
Linfoma de Células B/imunologia , Linfoma de Células B/patologia , Doenças Autoimunes/complicações , Linfócitos B/imunologia , Linfócitos B/patologia , Transformação Celular Neoplásica/imunologia , Transformação Celular Neoplásica/patologia , Infecções por Helicobacter/complicações , Hepatite C/complicações , Humanos , Linfoma de Células B/etiologia , Modelos Imunológicos , Fatores de Risco
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