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1.
Rev Gastroenterol Mex (Engl Ed) ; 89(1): 144-162, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38600006

RESUMO

Coagulation management in the patient with cirrhosis has undergone a significant transformation since the beginning of this century, with the concept of a rebalancing between procoagulant and anticoagulant factors. The paradigm that patients with cirrhosis have a greater bleeding tendency has changed, as a result of this rebalancing. In addition, it has brought to light the presence of complications related to thrombotic events in this group of patients. These guidelines detail aspects related to pathophysiologic mechanisms that intervene in the maintenance of hemostasis in the patient with cirrhosis, the relevance of portal hypertension, mechanical factors for the development of bleeding, modifications in the hepatic synthesis of coagulation factors, and the changes in the reticuloendothelial system in acute hepatic decompensation and acute-on-chronic liver failure. They address new aspects related to the hemorrhagic complications in patients with cirrhosis, considering the risk for bleeding during diagnostic or therapeutic procedures, as well as the usefulness of different tools for diagnosing coagulation and recommendations on the pharmacologic treatment and blood-product transfusion in the context of hemorrhage. These guidelines also update the knowledge regarding hypercoagulability in the patient with cirrhosis, as well as the efficacy and safety of treatment with the different anticoagulation regimens. Lastly, they provide recommendations on coagulation management in the context of acute-on-chronic liver failure, acute liver decompensation, and specific aspects related to the patient undergoing liver transplantation.


Assuntos
Insuficiência Hepática Crônica Agudizada , Transtornos da Coagulação Sanguínea , Humanos , Insuficiência Hepática Crônica Agudizada/complicações , Transtornos da Coagulação Sanguínea/complicações , Transtornos da Coagulação Sanguínea/terapia , Cirrose Hepática/complicações , Cirrose Hepática/terapia , Coagulação Sanguínea , Hemostasia
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 261: 120046, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34139661

RESUMO

The extremophile lichen Circinaria gyrosa (C. gyrosa) is one of the selected species within the BIOMEX (Biology and Mars Experiment) experiment. Here we present the Raman study of a biohint found in this lichen, called whewellite (calcium oxalate monohydrate), and other organic compounds and mineral products of the biological activity of the astrobiologically relevant model system C. gyrosa. Samples were exposed to space- and simulated Mars-like conditions during the EXPOSE-R2 mission parallel ground reference experiment MGR performed at the space- and planetary chambers of DLR-Cologne to study Mars' habitability and resistance to real space conditions. In this work, we complete the information of natural C. gyrosa about the process of diagenesis by the identification of carbonate crystals in the inner medulla together with the biomineral whewellite. The analysis by Raman spectroscopy of simulated Space and Mars exposed samples confirm alterations and damages of the photobiont part of the lichen and changes related to the molecular structure of whewellite. The conclusions of this work will be important to understand what are the effects to consider when biological systems are exposed to space or Mars-like conditions and to expand our knowledge of how life survives in most extreme conditions that is a prerequisite in future planetary exploration projects.


Assuntos
Líquens , Voo Espacial , Ascomicetos , Exobiologia , Meio Ambiente Extraterreno , Análise Espectral Raman
3.
J Food Sci ; 86(5): 1963-1978, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33884640

RESUMO

The stability after hydrostatic high pressure (HHP) (600 MPa/8 min/10 °C) and 180 days of storage at 4 and 20 °C was evaluated on Iberian dry-cured pork sausages (chorizo) packaged sliced or as half-pieces from pigs raised outdoors. Microbiological, physical-chemical, oxidative, and sensory changes were analyzed. The evolution of mesophilic aerobic and molds and yeasts counts was different in the half and sliced packaged pork sausages after processing and during storage. Sliced and half-packaged pork sausages had instrumental color stability after HHP and during storage. TBA-RS values were quite stable in both products. Protein oxidation values of pork sausage in half-products were increased by at 20 °C. In sliced pork sausage, both HPP and 20 °C storage favored the development of protein oxidation at the end of storage. In the sensory analysis, the sliced product developed more rancidity than the half-pieces during the storage. Therefore, the storage temperature has great importance for the preservation of dry-cured pork sausages, the increases of protein oxidation, and rancidity could reduce the shelf-life at these conditions. The presentation of the product is also relevant when HHP is applied, and this would also compromise the stability of the product when it is stored at room temperature. PRACTICAL APPLICATION: Chorizo is a traditional dry-fermented pork sausage that is generally considered to be microbiologically safe. However, the initial contamination of the raw materials, and some processes, such as the slicing or packaging, can compromise the safety of these products. Additionally, packaged dry-cured sausages require long shelf-life, and although they are normally stored at refrigeration temperature; sometimes, they are preserved at room temperature. The application of hydrostatic high pressure could increase the safety of dry-cured meat products even when they are stored at room temperature. Initial characteristics of each type of pork sausage could determine their technological behavior during processing or during storage under different conditions.


Assuntos
Conservação de Alimentos/métodos , Produtos da Carne/análise , Carne de Porco/análise , Temperatura , Animais , Fermentação , Humanos , Pressão Hidrostática , Suínos
5.
Rev Neurol ; 67(6): 203-209, 2018 Sep 16.
Artigo em Espanhol | MEDLINE | ID: mdl-30183060

RESUMO

INTRODUCTION: After Zika virus outbreak and the increase in the incidence of Guillain-Barre syndrome (GBS), the causal relationship has been studied, however a full etiological correlation has not been found. PATIENTS AND METHODS: From January 1 to December 31, 2017, patients with GBS were included. In addition to the basic serologies, enterovirus, herpes, Campylobacter, hepatitis B and C, TORCH, HIV, Brucella and Salmonella were requested. RESULTS: Cohort of seven male patients. Five patients analyzed cerebrospinal fluid reporting normal; all of them underwent brain scan, reporting normal. Neuroconduction was performed, resulting in acute inflammatory demyelinating polyneuropathy in four cases and acute motor axonal neuropathy in one case. All received intravenous immunoglobulins, five cases had a good prognosis and two deaths. No positive cases were reported to Zika virus. A positive case was reported to dengue and another to chikungunya. Five positive cases were reported to Campylobacter. One case positive to enterovirus. Dengue + Campylobacter coinfections were reported in one case and chikungunya + Campylobacter in another case. CONCLUSIONS: The present cohort shows that it was not possible to establish a causal relationship between GBS and Zika virus, but other viral and bacterial causal agents were identified, such as dengue, chikungunya and enterovirus, with the identification of Campylobacter cases even more remarkable.


TITLE: Agentes causales mas frecuentes del sindrome de Guillain-Barre en un hospital de Veracruz, Mexico.Introduccion. Con posterioridad a la oleada del virus del Zika y el incremento en la incidencia de sindrome de Guillain-Barre (SGB), se ha estudiado la relacion causal, pero no se ha encontrado una plena correlacion etiologica. Pacientes y metodos. Del 1 de enero al 31 de diciembre de 2017, se incluyeron pacientes con SGB. Ademas de las serologias basicas, se solicitaron determinaciones de enterovirus, virus del herpes, Campylobacter, hepatitis B y C, TORCH, virus de la inmunodeficiencia humana, Brucella y Salmonella. Resultados. Cohorte de siete pacientes de sexo masculino. A cinco pacientes se les analizo el liquido cefalorraquideo, que era normal. A todos se les realizo una tomografia encefalica, tambien normal, y se realizo neuroconduccion, que mostro polineuropatia inflamatoria desmielinizante aguda en cuatro casos y neuropatia motora axonal aguda en uno. Todos recibieron inmunoglobulinas intravenosas; tuvieron buen pronostico cinco casos y hubo dos defunciones. No se informo de casos positivos al virus del Zika. Hubo un caso positivo al dengue, uno al chikungunya, cinco a Campylobacter y uno a enterovirus. Se informo de coinfecciones de dengue + Campylobacter en un caso y de chikungunya + Campylobacter en otro. Conclusiones. La presente cohorte demuestra que no fue posible establecer una relacion causal entre el SGB y el virus del Zika, pero se identificaron otros agentes causales viricos y bacterianos, como dengue, chikungunya y enterovirus, y fue aun mas destacable la identificacion de los casos de Campylobacter.


Assuntos
Síndrome de Guillain-Barré/microbiologia , Adulto , Idoso de 80 Anos ou mais , Estudos Transversais , Síndrome de Guillain-Barré/diagnóstico , Hospitais Gerais , Humanos , Masculino , México , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
6.
Med Intensiva ; 41(9): 559-568, 2017 Dec.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28318674

RESUMO

Despite major advances in our understanding of the physiopathology of brain death (BD), there are important controversies as to which protocol is the most appropriate for organ donor management. Many recent reviews on this subject offer recommendations that are sometimes contradictory and in some cases are not applied to other critically ill patients. This article offers a review of the publications (many of them recent) with an impact upon these controversial measures and which can help to confirm, refute or open new areas of research into the most appropriate measures for the management of organ donors in BD, and which should contribute to discard certain established recommendations based on preconceived ideas, that lead to actions lacking a physiopathological basis. Aspects such as catecholamine storm management, use of vasoactive drugs, hemodynamic objectives and monitoring, assessment of the heart for donation, and general care of the donor in BD are reviewed.


Assuntos
Morte Encefálica , Guias de Prática Clínica como Assunto , Doadores de Tecidos , Obtenção de Tecidos e Órgãos/métodos , Morte Encefálica/diagnóstico , Catecolaminas/metabolismo , Cuidados Críticos/normas , Nutrição Enteral , Hemodinâmica , Humanos , Assistência Terminal/normas , Hormônios Tireóideos/uso terapêutico , Coleta de Tecidos e Órgãos , Obtenção de Tecidos e Órgãos/normas , Vasoconstritores/uso terapêutico
7.
Phys Chem Chem Phys ; 16(42): 22958-61, 2014 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-25255295

RESUMO

DFT calculations predict two different electronic structures of metal-molecule hybrids which are selected depending on the surface charge. While the metal-to-molecule CT states are very sensitive to the charge, the energies of the reverse molecule-to-metal CT processes are surprisingly not modified at all by the charge of the metal.

8.
Int J Food Microbiol ; 156(3): 209-13, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22525459

RESUMO

The combined effect of bacteriophages, vB_SauS-phi-IPLA35 (phiIPLA35) and vB_SauS-phi-IPLA88 (phiIPLA88), and high hydrostatic pressure (HHP) on Staphylococcus aureus Sa9 was evaluated in pasteurized whole milk under a simulated cold chain break, which was simulated by incubation of milk at 25°C for 48 h. Four-hundred MPa was found to be the most suitable pressure to be used in combination with these phages. Two different levels of staphylococcal initial contamination (1×10(4) and 1×10(6) CFU/mL) were tested. A synergistic effect between HHP and phages was observed in both cases. Compared to each single treatment, the combined treatment was able to reduce the initial S. aureus contamination below the detection limit (<10 CFU/mL). Bacteriophage performance in pressurize milk against S. aureus enabled milder hydrostatic pressure treatments, therefore phages can be regarded as a valuable hurdle on minimally processed food.


Assuntos
Bacteriófagos/patogenicidade , Pressão Hidrostática , Leite/microbiologia , Staphylococcus aureus/crescimento & desenvolvimento , Animais , Manipulação de Alimentos , Humanos , Pasteurização , Staphylococcus aureus/isolamento & purificação
9.
J Colloid Interface Sci ; 332(1): 130-5, 2009 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-19167008

RESUMO

Surface-enhanced Raman scattering (SERS) of hydroxybenzoic acids has been studied on silver sols in H(2)O and D(2)O solutions. The adsorption behavior of 4-hydroxybenzoic acid (4HBA) is different from that of salicylic (2HBA) and 3-hydroxybenzoic (3HBA) acids. It was concluded that 4HBA is adsorbed on silver nanoparticles (Ag(n)) as either oxidobenzoate (A(2-)) or hydroxybenzoate (A(-)), depending on the pH of the solution, given rise to a flat orientation. Both 2HBA and 3HBA acids are always adsorbed as hydroxybenzoates anions (A(-)) at pH >or=5 and link to the metal through the carboxylate group (Ag(n)--A(-)), standing more or less perpendicular to the metal surface. In the case of these monoanions, the selective enhancement of the bands is due mainly to a resonant electron or charge transfer process (ET or CT) from the metallic nanoparticles to the adsorbates, yielding the transient formation of the respective radical dianions (Ag(+)(n)--A(2-)). It is found that the enhanced bands, and especially the mode 8a;nu(ring), are related to the difference between the equilibrium structures of the adsorbate in its ground (A(-)) and CT-excited (A(2-)) states. In the SERS spectrum of 4HBA dianion, the contribution of CT mechanism is not observed.

10.
Biopolymers ; 82(4): 379-83, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16538609

RESUMO

The surface-enhanced Raman scattering (SERS) of salicylic acid (S) adsorbed on a silver sol in H(2)O and D(2)O has been investigated. At pH 5 or greater, the adsorbed species is the salicylate anion (2-hydroxybenzoate anion) (S(-)), which links to the metal nanoparticle (Ag(n)) through the carboxylate group (S(-)-Ag(n)). We demonstrate that the selective enhancement of the bands is due mainly to a resonant electron or charge transfer process (ET or CT) from the metallic nanoparticle to the adsorbate, yielding the transient formation of the respective radical dianion (S.(2-)-Ag(n) (+)). It is found that the enhanced bands, and especially mode 8a;nu(ring), are related to the differences between the equilibrium structures of the adsorbate in its ground (S(-)) and CT-excited states (S.(2-)).


Assuntos
Nanoestruturas/química , Salicilatos/química , Prata/química , Análise Espectral Raman/métodos , Adsorção , Transporte de Elétrons , Modelos Moleculares , Nanotecnologia/métodos
11.
Meat Sci ; 69(4): 609-15, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22063138

RESUMO

The effect of irradiation (0, 5 and 10 kGy) of vacuum-packaged Iberian dry-cured loin slices from pigs fed on concentrate (CON) or free-range reared (FRG) was studied in relation to colour changes, TBA-RS and hexanal content. Both, ionizing radiation and type of loin had a significant effect on the instrumental colour parameters of the samples. Irradiation resulted in significantly higher a*-values in both sets of loins, indicating a redder colour. Numerically calculated total colour difference (ΔE) changes were significantly less intense in CON vacuum-packaged dry-cured loin slices than in FRG samples and changed significantly at 10 kGy dose levels in both types of samples. TBA-RS numbers were significantly affected by irradiation dose and type of loin and increased linearly with dose in both types of slices. Increments in TBA-RS numbers in FRG loin slices was dose-dependent and was closely related to the type of dry-cured loin. Irradiation of dry-cured loin slices significantly increased hexanal contents in both groups of loins and the increases were dose-dependent and greater in FRG samples than in CON samples. Differences in the characteristics of the raw material and initial lipid oxidation level could play an important role in the irradiation-induced changes in vacuum-packaged dry-cured loin slices.

12.
Neuroscience ; 126(3): 651-6, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15183514

RESUMO

One-trial step-down inhibitory avoidance in rats involves the activation of two separate memory types, a short-term system (STM) that lasts 3-6 h, and a long-term system (LTM) that takes 3-6 h to be formed and lasts for many days or even months. Here we investigate the effect of nicotinic receptor (nAChR) ligands infused bilaterally in the hippocampus on STM and LTM formation and on LTM retrieval of this task. Rats were implanted with chronic cannulae in the CA1 region of the dorsal hippocampus, trained using a 0.5 mA foot shock, and tested twice, first 1.5 h after training to measure STM, and again at 24 h to measure LTM. The drugs used were the nAChR antagonists, mecamylamine (1, 3 and 10 microg/side) and dihydro-beta-erythroidine (DHbetaE; 2, 6 and 18 microg/side) and the agonist, nicotine (0.6, 1 and 3 microg/side). They were given either 15 min before training, immediately after training or 15 min prior to LTM retrieval. Mecamylamine and DHbetaE impaired and nicotine enhanced STM, LTM and retrieval similarly. The results indicate that nAChRs in CA1 participate in the regulation of both STM and LTM formation, and on the retrieval of LTM.


Assuntos
Aprendizagem da Esquiva/fisiologia , Hipocampo/metabolismo , Memória/fisiologia , Receptores Nicotínicos/metabolismo , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Injeções Intraventriculares , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Memória/efeitos dos fármacos , Agonistas Nicotínicos/administração & dosagem , Antagonistas Nicotínicos/administração & dosagem , Ratos , Ratos Wistar , Receptores Nicotínicos/efeitos dos fármacos
13.
Biopolymers ; 74(1-2): 141-5, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15137112

RESUMO

The vibration nu(SH) has never been observed in the surface-enhanced Raman scattering of mercaptoacetic acid recorded in a wide range of pH. This behavior enables us to deduce that the -SH group is deprotonated and links to the metal forming an Ag-S bond as 1-alkanethiols do. On the contrary, the carboxylic or carboxylate groups do not link to the metal and the carboxylic group is preserved even at pH values under which it should be deprotonated. This fact enables the stabilization of the adsorbed monolayer by removing the electrostatic repulsions between -COO(-) groups and by the formation instead of hydrogen bonds between carboxylic groups. Only under rather basic conditions (pH > 8) does the carboxylic groups dissociate, but the nu(s)(OCO) band is neither enhanced nor shifted toward low frequencies.


Assuntos
Coloides/química , Análise Espectral Raman/métodos , Tioglicolatos/química , Adsorção , Ácidos Carboxílicos/metabolismo , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Modelos Químicos , Eletricidade Estática
14.
J Colloid Interface Sci ; 263(2): 357-63, 2003 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-12909024

RESUMO

Raman and SERS spectra of phenylacetic acid and alpha-phenylglycine on silver sols have been recorded at several concentrations and pH values. The alpha-phenylglycine has been also studied in D(2)O. The respective vibrational assignments have been proposed and the analysis of the SERS spectra has made it possible to conclude that phenylacetic acid links to the metal through its carboxylate group only, while alpha-phenylglycine links also through its amino group. In both cases the aromatic ring seems to be almost perpendicular to the metal surface. On the other hand, the contribution of the charge transfer (CT) mechanism to the enhancement of the SERS spectra has been calculated as well and it is found to be very important in both molecules. The band most enhanced by this mechanism is that of vibration 8a, mainly in alpha-phenylglycine.


Assuntos
Hidrocarbonetos/química , Fenilacetatos/química , Polímeros/química , Tensoativos/química , Adsorção , Fenômenos Biofísicos , Biofísica , Carbono/química , Microscopia de Força Atômica , Modelos Químicos , Aço/química , Temperatura
15.
Ann Epidemiol ; 10(1): 5-13, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10658684

RESUMO

PURPOSE: Earthquakes pose a persistent but unpredictable health threat. Although knowledge of geologic earthquake hazards for buildings has increased, spatial relations between injuries and seismic activity have not been explained. METHODS: Fatal and hospital-admitted earthquake injuries due to the 1994 Northridge Earthquake were identified. Geographical Information Systems software was used to map all injury locations. Injuries were analyzed with regard to distance from the earthquake epicenter, the Modified Mercalli Intensity Index, peak ground acceleration, and proportion of damaged residential buildings. RESULTS: Injury severity was inversely related to distance from the epicenter and increased with increasing ground motion and building damage. However, injury incidence and severity were not completely predicted by seismic hazard and building damage, and injuries of all severities occurred in a large geographic area. Average distance to the epicenter was smallest for injuries related to falling building parts and largest for cutting/piercing injuries and falls. CONCLUSIONS: The injuries from the Northridge Earthquake extended beyond the areas of highest environmental activity. Factors such as age and activity during the earthquake may be equally important in predicting injury from earthquakes as seismic features.


Assuntos
Desastres , Admissão do Paciente/estatística & dados numéricos , Ferimentos e Lesões/mortalidade , California/epidemiologia , Geografia , Humanos
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