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1.
J Theor Biol ; : 111853, 2024 May 18.
Article in English | MEDLINE | ID: mdl-38768893

ABSTRACT

Fungal pellets are hierarchical systems that can be found in an ample variety of applications. Modeling transport phenomena in this type of systems is a challenging but necessary task to provide knowledge-based processes that improve the outcome of their biotechnological applications. In this work, an upscaled model for total mass and momentum transport in fungal pellets is implemented and analyzed, using elements of the volume averaging and adjoint homogenization methods departing from the governing equations at the microscale in the intracellular and extracellular phases. The biomass is assumed to be composed of a non-Newtonian fluid and the organelles impervious to momentum transport are modeled as a rigid solid phase. The upscaled equations contain effective-medium coefficients, which are predicted from the solution of adjoint closure problems in a three-dimensional periodic domains representative of the microstructure. The construction of these domains was performed for Laccaria trichodermophora based on observations of actual biological structures. The upscaled model was validated with direct numerical simulations in homogeneous portions of the pellets core. It is shown that no significant differences are observed when the dolipores are open or closed to fluid flow. By comparing the predictions of the average velocity in the extracellular phase resulting from the upscaled model with those from the classical Darcy equation (i.e., assuming that the biomass is a solid phase) the contribution of the intracellular fluid phase was evidenced. This work sets the foundations for further studies dedicated to transport phenomena in this type of systems.

2.
Odontol. vital ; (39): 56-75, jul.-dic. 2023. tab, graf
Article in Spanish | LILACS, SaludCR | ID: biblio-1550587

ABSTRACT

Resumen Los pacientes que se encuentran bajo tratamiento de anticoagulantes orales, presentan alteraciones en distintas etapas de la hemostasia, lo que conlleva a tener implicancias y consideraciones médico/quirúrgicas durante su atención. En la actualidad, no existe un consenso en relación con el manejo odontológico de estos pacientes que serán sometidos a procedimientos quirúrgicos, llevando a protocolos clínicos que siguen diversas posturas, como la de disminuir la ingesta farmacológica del anticoagulante, sustituir con heparina y la de mantener el tratamiento bajo control. Objetivo Establecer el manejo estomatológico del paciente que se encuentra en tratamiento de anticoagulante oral mediante una revisión profunda de la literatura Materiales y método Se realizó una búsqueda de revisión bibliográfica manualmente de artículos indexados a las bases de datos de PUBMED y EBSCO que correspondiesen a las palabras "cirugía bucal", "anticoagulantes", "atención dental" y "hemorragia oral". En cuanto a los criterios de inclusión, se consideraron revisiones bibliográficas, estudios observacionales, ensayos clínicos, guías, revisiones sistemáticas y metaanálisis publicados entre noviembre de 2005 y 2022, en idiomas inglés o español. Conclusiones Existen múltiples protocolos para la atención del paciente anticoagulado que será sometido bajo procedimiento de cirugía oral menor. Es importante considerar el anticoagulante utilizado, motivo, control de este, el procedimiento a realizar en el paciente y medidas hemostáticas tanto intra como postoperatorias por realizar, tras analizar lo anterior, se advierte que disminuir la ingesta del fármaco para realizar el procedimiento, puede ser más perjudicial al paciente como al clínico, por lo tanto se sugiere mantener el tratamiento antitrombótico y realizar un correcto manejo médico/quirúrgico.


Abstract Patients undertaking oral anticoagulant treatment may experience alterations in different stages of hemostasis, which lead to medical/surgical implications and considerations during their care. Currently, there is no consensus regarding the dental management of these patients, as they go through surgical procedures. This leads to clinical protocols that follow numerous approaches, such as reducing the pharmacological intake of the anticoagulant, replacing it with heparin, and maintaining the controlled treatment. Objective: To establish the stomatological management of the patient undergoing oral anticoagulant treatment through an in depth review of the literature. Materials and Method: A manual bibliographic review search of articles indexed to the PUBMED and EBSCO databases corresponding to the words "oral surgery", "oral bleeding", "anticoagulants" and "dental management" was performed. Regarding the inclusion criteria: bibliographic reviews, observational studies, clinical trials, guidelines, systematic reviews, and meta-analyses published between November 2005 and 2022, in English or Spanish, were considered. Conclusion: There are multiple protocols for the care of the anticoagulated patient who will undergo a minor oral surgery procedure. It is important to reflect on the anticoagulant used, the reason for it, its supervision, the surgical procedure that will be undertaken by the patient, and both intraoperative and postoperative hemostatic measures to be implemented. After analyzing the above, it is noted that reducing the intake of the drug to perform the surgical procedure may be harmful to the patient and to the clinician, therefore it is suggested to maintain the antithrombotic treatment and carry out a correct medical/surgical management.


Subject(s)
Humans , Surgery, Oral/methods , Anticoagulants/therapeutic use , Oral Hemorrhage/drug therapy , Dental Care
3.
Article in English, Spanish | MEDLINE | ID: mdl-38101513

ABSTRACT

INTRODUCTION: A high prevalence of low testosterone levels has been reported in men with prostate cancer. The use of testosterone therapy in men with a history of prostate cancer is still controversial, and there is uncertainty regarding the management of these patients. METHODS: We analyzed the European and American guidelines on this topic and presented the clinical experience in the management of patients with low testosterone levels and a history of prostate cancer in one of the world's leading cancer centers. RESULTS: According to the published evidence to date, testosterone therapy in men with prostate cancer does not increase the risk of prostate cancer recurrence in the short and medium term, but there is a lack of data on the long term. Symptomatic men with low testosterone levels who are candidates for this therapy need a thorough clinical evaluation before commencing testosterone therapy. Evaluation of prostate cancer history including type of treatment administered, pathologic stage of prostate cancer and prostate specific antigen should be requested before and during testosterone treatment to assess its trend. CONCLUSION: Prostate-specific antigen should remain undetectable after radical prostatectomy or stable after radiotherapy. Otherwise, it would be a sign of uncontrolled prostate cancer, and the patient may require cessation of testosterone therapy and referral to oncology for further evaluation.

4.
J Am Coll Cardiol ; 66(19): 2075-2088, 2015.
Article in English | Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1063629

ABSTRACT

BACKGROUND:Cardiac biomarker release signifying myocardial injury post-transcatheter aortic valve replacement (TAVR) is common, yet its clinical impact within a large TAVR cohort receiving differing types of valve and procedural approaches is unknown.OBJECTIVES:This study sought to determine the incidence, clinical impact, and factors associated with cardiac biomarker elevation post TAVR.METHODS:This multicenter study included 1,131 consecutive patients undergoing TAVR with balloon-expandable (58%) or self-expandable (42%) valves. Transfemoral and transapical (TA) approaches were selected in 73.1% and 20.3% of patients, respectively. Creatine kinase-myocardial band (CK-MB) measurements were obtained at baseline and at several time points within the initial 72 h post TAVR. Echocardiography was performed at baseline and at 6- to 12-month follow-up.RESULTS:Overall, 66% of the TAVR population demonstrated some degree of myocardial injury as determined by a rise in CK-MB levels (peak value: 1.6-fold [interquartile range (IQR): 0.9 to 2.8-fold]). A TA approach and major procedural complications were independently associated with higher peak of CK-MB levels (p < 0.01 for all), which translated into impaired systolic left ventricular function at 6 to 12 months post TAVR (p < 0.01). A greater rise in CK-MB levels independently associated with an increased 30-day, late (median of 21 [IQR: 8 to 36] months) overall and cardiovascular mortality (p < 0.001 for all)...


Subject(s)
Biomarkers , Creatine Kinase , Carotid Stenosis , Transcatheter Aortic Valve Replacement
5.
Clin Radiol ; 68(11): e617-23, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23932678

ABSTRACT

AIM: To compare T1-weighted (W) fat-water separation (Dixon's technique) with T1W fat-saturation (FS) and T2W Dixon with short-tau inversion recovery (STIR) images for fat suppression in a short-bore MRI machine. MATERIALS AND METHODS: Thirteen patients with lumbar disease were studied on using 1.5 T MRI machine. The protocol included T1 FS (with contrast medium administration) and/or STIR and T1W and/or T2W Dixon, for comparison. Three neuroradiologists scored the images from the two-pairs of techniques for fat suppression uniformity and lesion conspicuity. Clinical usefulness of fat-only images was also evaluated. RESULTS: Regarding uniformity of fat suppression, mean scores were 2.28 (±0.49), 3.06 (±0.49), 2.39 (±0.49), and 3.15 (±0.35) for T1W FS, T1W Dixon, STIR, and T2W Dixon sequences, respectively. For the same pulse sequences, lesion conspicuity scores were 2.78 (±0.50), 2.78 (±0.27), 2.76 (±0.47), and 2.91 (±0.4), respectively. Both T1W and T2W Dixon sequences showed more homogeneous fat-suppression when compared to T1W FS (p = 0.026) and STIR (p = 0.008) techniques, but no significant difference was found for lesion conspicuity. Mean scores for the diagnostic utility of fat-only maps were, respectively, 1.72 (±0.39) and 2.48 (±0.50) for T1W and T2W Dixon. CONCLUSION: Fat suppression quality was superior with Dixon when compared to the conventional sequences, but not lesion conspicuity, suggesting that both techniques are reliable for diagnosis. Dixon may be advantageous in cases where inhomogeneity artefacts are an issue. Water-only maps appear to be useful in the clinical setting.


Subject(s)
Intervertebral Disc Degeneration/diagnosis , Intervertebral Disc Displacement/diagnosis , Lumbar Vertebrae/pathology , Magnetic Resonance Imaging/methods , Adult , Aged, 80 and over , Contrast Media , Female , Gadolinium , Humans , Image Enhancement/methods , Image Processing, Computer-Assisted/methods , Male , Middle Aged , Observer Variation , Prospective Studies , Reproducibility of Results , Young Adult
6.
J Chem Phys ; 137(15): 154109, 2012 Oct 21.
Article in English | MEDLINE | ID: mdl-23083150

ABSTRACT

We perform a numerical investigation of the transport of Brownian particles driven by a zero-mean periodic force across two-dimensional arrays of obstacles with finite length. By applying axial and transversal driving forces relative to the diffusion transport direction, the effective diffusivity is determined as function of the array geometry and the driving frequency, finding excess diffusion peaks at certain frequency ranges. The results indicate that a suitable selection of the axial and transversal frequencies yields enhanced diffusion transport along the axial direction. Symmetric and asymmetric arrays are considered, showing that the asymmetry has a detrimental effect in the magnitude of the excess diffusion peaks. This suggests that enhanced diffusion is obtained because the oscillatory driving force exploits preferential transport channels, whose effective obstacle spacing is maximized under symmetric configurations.

7.
J Chem Phys ; 135(17): 174102, 2011 Nov 07.
Article in English | MEDLINE | ID: mdl-22070287

ABSTRACT

Geometric stochastic resonance of Brownian particles diffusing across a converging conic channel subject to oscillating forces is studied in this paper. Conic channel geometries have been previously considered as a model for transport of particles in biological membranes, zeolites, and nanostructures. For this system, a broad excess peak of the effective diffusion above the free diffusion limit is exhibited over a wide range of frequencies, suggesting a synchronization effect in the confining geometry as particles respond to the periodic modulation of the external force. This indicates that the geometric stochastic resonance effect with unbiased ac forces can be exploited for improving the transport of particles in complex geometries.

8.
Rev. chil. psicoanal ; 24(2): 100-107, dic. 2007.
Article in Spanish | LILACS | ID: lil-600265

ABSTRACT

La autora desarrolla las características de la latencia y su relación con la violencia. Este es un período precario, donde la turbulencia emocional se esconde detrás de paredes muy finas y frágiles. Los primeros vínculos son fundamentales para un tránsito satisfactorio por este etapa, pues ofrece al niño la posibilidad de adquirir y ampliar sus áreas de satisfación y conocimiento, permitiéndole una inserción más amplia en el mundo y en la cultura. La violencia en la latencia surge cuando las condiciones para su desarrollo no se alcanzan, y el niño permanece aprisionado en las cuestiones de la primera infancia, desde las narcisistas primarias hasta las complejas cuestiones pulsionales. Se ilustran estas ideas con la presentación de dos casos clínicos en los cuales muestra cómo el fracaso en la adquisición de sublimaciones exitosas y el pasado extremadamente presente no permiten vivir el presente ni ocuparse del futuro.


The author exposes the characteristics of latency and its relation with violence. This is a precarious period in which emotional turbulence hides behind thin a fragile walls. First bonds are fundamental for a satisfactory transit through this stage, offering the child the possibility of acquiring and expanding its satisfaction and knowledge, allowing a broader insertion in the world and its culture. Violence in latency appears when the conditions for its development aren't reached, and the child remains imprisoned in early childhood matters, from the primary narcissistic ones to the complex "pulsiona" matters. The author illustrates this ideas with the presentation of two clinical cases in which she shows how failure in the acquisition of successful sublimation and the past being extremely present do not allow them to enjoy the present nor take care of the future.


Subject(s)
Humans , Male , Female , Child , Adolescent , Latency Period, Psychological , Psychoanalysis , Violence/psychology
9.
J Agric Food Chem ; 48(12): 6200-4, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11312792

ABSTRACT

Free and glycosidically bound volatiles obtained from the fruit pulp of Sicana odorifera by liquid-liquid extraction and by chromatography, followed by enzymatic hydrolysis with Rohapect D5L, respectively, were analyzed by capillary gas chromatography (HRGC), HRGC-mass spectrometry (HRGC-MS), and HRGC-Olfatometry (HRGC-O) analyses. A total of 37 free volatiles was detected, with the major components being 3-methyl-2-butanol, 3-hydroxy-2-butanone, ethyl 3-hydroxybutanoate, and (Z)-3-hexenol. Among the 22 detected glycosidically bound compounds, 4-hydroxybenzyl methyl ether, 4-hydroxybenzyl alcohol, and 2-phenylethanol were found to be the major constituents. Additionally, two glucoconjugates were isolated in pure form by multilayer coil countercurrent chromatography (MLCCC) of the glycosidic extrac and further purification. Their structures were elucidated by MS and NMR analyses to be the novel [4-(beta-D-glucopyranosyloxy)benzyl] 2,3-dihydroxy-3-methylbutanoate 2, and the known 4-(beta-D-glucopyranosyloxy)benzyl alcohol 1. Compounds 1 and 2 are precursors of 4-hydroxybenzyl alcohol, one of the major volatiles generated by enzymatic hydrolysis of the glycosidic fraction.


Subject(s)
Cucurbitaceae/chemistry , Glucosides/analysis , Gas Chromatography-Mass Spectrometry , Glucosides/classification , Smell , Volatilization
10.
J Diabetes Complications ; 12(5): 239-45, 1998.
Article in English | MEDLINE | ID: mdl-9747639

ABSTRACT

We investigated the role of belief in conventional medicine, the type of medical care, and familiar and socioeconomic factors on the adherence to treatment in non-insulin-dependent diabetes mellitus (NIDDM) patients. In a cross-sectional design, we selected 156 patients from two institutions, who agreed to fill out a questionnaire, which included general data, socioeconomic level, somatometric data, type of medical care, complications, if they had friends and relatives with diabetes, the family function, and a score on the belief in conventional medicine. Factors associated with adherence to diet and medication were analyzed. Patients had a mean age of 55.6 years and 8.9 years since diagnosis. A total of 51.3% of them were not covered by social security, and 62.8% received attention by a general physician. Patients under the care of a specialist had better adherence to diet and medication, and better belief in conventional medicine. The principal factor associated with adherence to medication and diet was the belief in conventional medicine (p < 0.001 in both). Adherence to diet was also associated with the socioeconomic level (p=0.001) and years since diagnosis (p=0.004). Adherence to medication was also associated with schooling (p=0.001). We concluded that belief in conventional medicine is strongly associated with adherence to treatment and other factors such as schooling, socioeconomic level, and medical care under a specialist; adherence to diet was better in patients with more years since diagnosis.


Subject(s)
Attitude to Health , Diabetes Mellitus, Type 2/therapy , Cross-Sectional Studies , Family Health , Female , Humans , Linear Models , Male , Middle Aged , Patient Compliance , Socioeconomic Factors , Surveys and Questionnaires
11.
J Biomed Mater Res ; 20(9): 1277-93, 1986.
Article in English | MEDLINE | ID: mdl-3097022

ABSTRACT

Histopathologic evaluation of three metal alloys for chronic implantation in the central nervous system (CNS) was undertaken in rabbits. Throughout the 8 month evaluation period the inflammatory response to the alloys was bland. Two of the alloys tested (chromium based MP35N, Trademark of the Standard Pressed Steel Company, and a stainless steel alloy, BG42 VacArc, Trademark of Latrobe Steel) appeared suitable as CNS implants. The third alloy (stainless steel 440C, Carpenter Steel Company) showed more corrosion than the other alloys, and may be less suitable for implantation. While E. cuniculi infection was found in four rabbits, the infection did not directly interfere with the assessment of the histologic changes directly due to the implants. Autoantibodies to a brain constituent were not observed.


Subject(s)
Autoantibodies/analysis , Brain/pathology , Chromium Alloys , Prostheses and Implants , Protozoan Infections/pathology , Stainless Steel , Animals , Encephalitozoon cuniculi/isolation & purification , Enzyme-Linked Immunosorbent Assay , Fluorescent Antibody Technique , Rabbits
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