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1.
Environ Pollut ; 345: 123397, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38272166

RESUMEN

The occurrence of contaminants of emerging concern (CECs) in environmental systems is gradually more studied worldwide. However, in Latin America, the presence of contaminants of emerging concern, together with their environmental and toxicological impacts, has recently been gaining wide interest in the scientific community. This paper presents a critical review about the source, fate, and occurrence of distinct emerging contaminants reported during the last two decades in various countries of Latin America. In recent years, Brazil, Chile, and Colombia are the main countries that have conducted research on the presence of these pollutants in biological and aquatic compartments. Data gathered indicated that pharmaceuticals, pesticides, and personal care products are the most assessed CECs in Latin America, being the most common compounds the followings: atrazine, acenaphthene, caffeine, carbamazepine, ciprofloxacin, diclofenac, diuron, estrone, losartan, sulfamethoxazole, and trimethoprim. Most common analytical methodologies for identifying these compounds were HPLC and GC coupled with mass spectrometry with the potential to characterize and quantify complex substances in the environment at low concentrations. Most CECs' monitoring and detection were observed near to urban areas which confirm the out-of-date wastewater treatment plants and sanitization infrastructures limiting the removal of these pollutants. Therefore, the implementation of tertiary treatment should be required. In this tenor, this review also summarizes some studies of CECs removal using electrochemical advanced oxidation processes that showed satisfactory performance. Finally, challenges, recommendations, and future perspectives are discussed.


Asunto(s)
Contaminantes Ambientales , Contaminantes Químicos del Agua , América Latina , Aguas Residuales , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente/métodos , Contaminantes Ambientales/análisis
2.
Sensors (Basel) ; 22(18)2022 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-36146368

RESUMEN

Cloud storage has become a keystone for organizations to manage large volumes of data produced by sensors at the edge as well as information produced by deep and machine learning applications. Nevertheless, the latency produced by geographic distributed systems deployed on any of the edge, the fog, or the cloud, leads to delays that are observed by end-users in the form of high response times. In this paper, we present an efficient scheme for the management and storage of Internet of Thing (IoT) data in edge-fog-cloud environments. In our proposal, entities called data containers are coupled, in a logical manner, with nano/microservices deployed on any of the edge, the fog, or the cloud. The data containers implement a hierarchical cache file system including storage levels such as in-memory, file system, and cloud services for transparently managing the input/output data operations produced by nano/microservices (e.g., a sensor hub collecting data from sensors at the edge or machine learning applications processing data at the edge). Data containers are interconnected through a secure and efficient content delivery network, which transparently and automatically performs the continuous delivery of data through the edge-fog-cloud. A prototype of our proposed scheme was implemented and evaluated in a case study based on the management of electrocardiogram sensor data. The obtained results reveal the suitability and efficiency of the proposed scheme.


Asunto(s)
Nube Computacional , Redes de Comunicación de Computadores , Electrocardiografía , Internet
3.
Chemosphere ; 306: 135530, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35792212

RESUMEN

A sensitive electroanalytical method for the determination of arsenite, based on a heterostructure of aminated multiwalled carbon nanotubes and gold nanoparticles, was applied in an electrocoagulation (EC) treatment for the elimination of arsenite. A sensitive quantitative response was obtained in the determination of As3+ in a secondary effluent from a wastewater treatment plant from Santiago (Chile). The preconcentration stage was optimized through a Central Composite Face design, and the most sensitive peak current was obtained at 200 s and -600 mV of time and accumulation potential, respectively, after a differential pulse voltammetry sweep. Electroanalytical determination was possible in an interval between 42.89 and 170.00 µg L-1 with a detection limit of 0.39 µg L-1, obtaining recoveries over 99.1%. The developed method was successfully applied in an electrocoagulation treatment to remove 250 µg L-1 of arsenite from a polluted effluent in a batch system. Complete arsenite removal was achieved using a steel EC system with a current density of 6.0 mA cm-2 in less than 3 min of treatment.


Asunto(s)
Arsenitos , Nanopartículas del Metal , Nanotubos de Carbono , Arsenitos/química , Técnicas Electroquímicas , Electrocoagulación/métodos , Electrodos , Oro/química
4.
Sensors (Basel) ; 22(13)2022 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-35808523

RESUMEN

In emergent technologies, data integrity is critical for message-passing communications, where security measures and validations must be considered to prevent the entrance of invalid data, detect errors in transmissions, and prevent data loss. The SHA-256 algorithm is used to tackle these requirements. Current hardware architecture works present issues regarding real-time balance among processing, efficiency and cost, because some of them introduce significant critical paths. Besides, the SHA-256 algorithm itself considers no verification mechanisms for internal calculations and failure prevention. Hardware implementations can be affected by diverse problems, ranging from physical phenomena to interference or faults inherent to data spectra. Previous works have mainly addressed this problem through three kinds of redundancy: information, hardware, or time. To the best of our knowledge, pipelining has not been previously used to perform different hash calculations with a redundancy topic. Therefore, in this work, we present a novel hybrid architecture, implemented on a 3-stage pipeline structure, which is traditionally used to improve performance by simultaneously processing several blocks; instead, we propose using a pipeline technique for implementing hardware and time redundancies, analyzing hardware resources and performance to balance the critical path. We have improved performance at a certain clock speed, defining a data flow transformation in several sequential phases. Our architecture reported a throughput of 441.72 Mbps and 2255 LUTs, and presented an efficiency of 195.8 Kbps/LUT.

5.
PeerJ Comput Sci ; 7: e731, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34712800

RESUMEN

In an Inter-Organizational Business Process (IOBP), independent organizations (collaborators) exchange messages to perform business transactions. With process mining, the collaborators could know what they are actually doing from process execution data and take actions for improving the underlying business process. However, process mining assumes that the knowledge of the entire process is available, something that is difficult to achieve in IOBPs since process execution data generally is not shared among the collaborating entities due to regulations and confidentiality policies (exposure of customers' data or business secrets). Additionally, there is an inherently lack-of-trust problem in IOBP as the collaborators are mutually untrusted and executed IOBP can be subject to dispute on counterfeiting actions. Recently, Blockchain has been suggested for IOBP execution management to mitigate the lack-of-trust problem. Independently, some works have suggested the use of Blockchain to support process mining tasks. In this paper, we study and address the problem of IOBP mining whose management and execution is supported by Blockchain. As contribution, we present an approach that takes advantage of Blockchain capabilities to tackle, at the same time, the lack-of-trust problem (management and execution) and confident execution data collection for process mining (discovery and conformance) of IOBPs. We present a method that (i) ensures the business rules for the correct execution and monitoring of the IOBP by collaborators, (ii) creates the event log, with data cleaning integrated, at the time the IOBP executes, and (iii) produces useful event log in XES and CSV format for the discovery and conformance checking tasks in process mining. By a set of experiments on real IOBPs, we validate our method and evaluate its impact in the resulting discovered models (fitness and precision metrics). Results revealed the effectiveness of our method to cope with both the lack-of-trust problem in IOBPs at the time that contributes to collect the data for process mining. Our method was implemented as a software tool available to the community as open-source code.

6.
Environ Sci Pollut Res Int ; 28(19): 23753-23766, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33099736

RESUMEN

In this study, the simultaneous degradation of antibiotics (ampicillin, sulfamethazine, and tetracycline; and non-steroidal anti-inflammatories (diclofenac and salicylic acid)) including the total organic carbon abatement by solar photoelectro-Fenton process was assessed. Eight liters of solution containing the mixture of the five pharmaceuticals in 1 mmol L-1 Fe2+, 0.05 mol L-1 Na2SO4 at pH 3 and 35 °C were electrolyzed applying different current densities (j = 10, 25, and 50 mA cm-2) in a solar-electrochemical pilot plant. The pilot plant was equipped with an electrochemical filter press cell with a dimensionally stable anode (DSA type) and an air-diffusion cathode coupled to a solar photoreactor exposed directly to sunlight radiation. All pharmaceuticals were degraded during the first 10 min. A TOC removal efficiency of 99.2% after 100 min of treatment with an energy consumption of 534.23 kW h (kgTOC)-1 and 7.15 kW h m-3 was achieved. The pharmaceutical concentration decay followed a pseudo-first-order kinetics. The specific energy per unit of mass of ampicillin, diclofenac, salicylic acid, sulfamethazine, and tetracycline was obtained at 11.73, 19.56, 35.2, 11.73, and 39.32 kW h (kgPD)-1 for ampicillin, diclofenac, salicylic acid, sulfamethazine, and tetracycline, respectively. With our results, we demonstrated that SPEF is an emerging technology for the treatment of this type of pollutants in short time.


Asunto(s)
Contaminantes Ambientales , Preparaciones Farmacéuticas , Contaminantes Químicos del Agua , Técnicas Electroquímicas , Electrodos , Peróxido de Hidrógeno , Hierro , Oxidación-Reducción , Luz Solar
8.
PLoS One ; 15(8): e0237811, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32833983

RESUMEN

BACKGROUND: Epidemiological studies commonly identify the clinical characteristics and survival outcomes of patients with breast cancer at five years. Our study aims to describe the sociodemographic, clinicopathological characteristics and determine the long-term event-free survival (EFS) and overall survival (OS) of a Peruvian population with triple-negative breast cancer. METHODS: We reviewed the medical records of new cases treated at a single institution in the period 2000-2014. The survival analysis included patients with stages I-IV. Survival estimates at 10 years were calculated with the Kaplan-Meier method and compared with the Log-rank test. We further used multivariate Cox regression analysis to calculate prognostic factors of recurrence and mortality. RESULTS: Among the 2007 patients included, the median age at diagnosis was 49 years (19-95 years). Most patients presented histologic grade III (68.7%), tumor stage II (34.2%), and III (51.0%) at diagnosis. Local and distant relapse was present in 31.9 and 51.4% of the patients, respectively. The most frequent sites of metastasis were the lungs (14.5%), followed by bone (9.7%), brain (9.6%), and liver (7.9%). The median follow-up was 153 months. At 3, 5, and 10 years, the EFS of the population was 55%, 49%, and 41%, respectively, while the OS was 64%, 56%, and 47%, respectively. Moreover, an N3 lymph node status was the most important prognostic factor for both disease relapse (HR: 2.54, 95% CI: 2.05-3.15) and mortality (HR: 2.51, 95% CI: 2.01-3.14) at ten years. An older age and higher T staging were associated with a worse OS, while patients who received radiotherapy and adjuvant chemotherapy had better survival rates. CONCLUSION: The sociodemographic features of Peruvian patients with TNBC are similar to those of other populations. However, our population was diagnosed at more advanced clinical stages, and thus, EFS and OS were lower than international reports while prognostic factors were similar to previous studies.


Asunto(s)
Neoplasias de la Mama Triple Negativas/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Quimioterapia Adyuvante , Supervivencia sin Enfermedad , Femenino , Humanos , Persona de Mediana Edad , Terapia Neoadyuvante , Metástasis de la Neoplasia , Perú/epidemiología , Resultado del Tratamiento , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/patología , Neoplasias de la Mama Triple Negativas/cirugía , Adulto Joven
9.
Sensors (Basel) ; 20(2)2020 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-31936004

RESUMEN

Vehicular ad-hoc Networks (VANETs) are recognized as a cornerstone of Intelligent Transportation Systems (ITS) to enable the exchange of information among vehicles, which is crucial for the provision of safety-related and entertainment applications. However, practical useful realizations of VANETs are still missing, mainly because of the elevated costs and the lack of a final standardization. In this regard, the feasibility of using smartphones as nodes in VANETs has been explored focusing on small-scale deployments to mainly validate single-hop communication capabilities. Moreover, existing smartphone-based platforms do not consider two crucial requirements in VANETs, namely, multi-hop communication and the provision of security services in the message dissemination process. Furthermore, the problem of securing message dissemination in VANETs is generally analyzed through simulation tools, while performance evaluations on smart devices have not been reported so far. In this paper, we aim to fill this void by designing a fully on-device platform for secure multi-hop message dissemination. We address the multi-hop nature of message dissemination in VANETs by integrating a location-based protocol that enables the selection of relay nodes and retransmissions criteria. As a main distinction, the platform incorporates a novel certificateless cryptographic scheme for ensuring data integrity and nodes' authentication, suitable for VANETs lacking of infrastructure.

10.
Breast Dis ; 39(1): 29-35, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31903977

RESUMEN

BACKGROUND: Breast-conserving surgery (BCS) as an alternative to total mastectomy (TM) in patients with early-stage triple-negative breast cancer (TNBC) is not widely spread. OBJECTIVE: We aimed to compare the overall survival (OS) and disease-free survival (DFS) between both surgical approaches in early-stage TNBC patients at 10 years. METHODS: We conducted a retrospective cohort study in TNBC female patients with stage I-IIa, treated at a single-center during the period of 2000-2014. We estimated and compared the survival rates with the Kaplan Meier and Long-rank test. Propensity scores were calculated with the generalized boosted regression model and were used in the multivariate Cox regression analysis with the covariate adjustment method. RESULTS: We included 288 patients, 111 in the BCS vs. 177 in the TM group. The median follow-up was 102 months. Moreover, the patients in the BCS group had superior OS (85% vs. 81%, p = 0.56) and DFS (83% vs. 80%, p = 0.42) at 10 years. In the multivariate Cox analysis, BCS decreased the mortality risk (HR: 0.79, 95% CI: 0.37-1.67, p = 0.538), and the locoregional or distant recurrence risk (HR: 0.67, 95% CI: 0.32-1.41, p = 0.294), albeit with no statistical significance. CONCLUSION: BCS is a safe alternative to TM in Latin-American patients with early-stage TNBC.


Asunto(s)
Mastectomía Segmentaria , Mastectomía Simple , Neoplasias de la Mama Triple Negativas/cirugía , Adulto , Anciano , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , América Latina , Persona de Mediana Edad , Estadificación de Neoplasias , Puntaje de Propensión , Estudios Retrospectivos , Resultado del Tratamiento , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico
11.
Sensors (Basel) ; 19(3)2019 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-30744202

RESUMEN

Making Elliptic Curve Cryptography (ECC) available for the Internet of Things (IoT) and related technologies is a recent topic of interest. Modern IoT applications transfer sensitive information which needs to be protected. This is a difficult task due to the processing power and memory availability constraints of the physical devices. ECC mainly relies on scalar multiplication (kP)-which is an operation-intensive procedure. The broad majority of kP proposals in the literature focus on performance improvements and often overlook the energy footprint of the solution. Some IoT technologies-Wireless Sensor Networks (WSN) in particular-are critically sensitive in that regard. In this paper we explore energy-oriented improvements applied to a low-area scalar multiplication architecture for Binary Edwards Curves (BEC)-selected given their efficiency. The design and implementation costs for each of these energy-oriented techniques-in hardware-are reported. We propose an evaluation method for measuring the effectiveness of these optimizations. Under this novel approach, the energy-reducing techniques explored in this work contribute to achieving the scalar multiplication architecture with the most efficient area/energy trade-offs in the literature, to the best of our knowledge.

12.
Rev Chilena Infectol ; 35(4): 445-447, 2018 Aug.
Artículo en Español | MEDLINE | ID: mdl-30534933

RESUMEN

Infection with Strongyloides stercoralis is a common parasitic infection in tropical and subtropical regions, including the Peruvian Amazon. The clinical manifestations are varied in patients with immunocompromised disease, and the systemic spread of the disease is frequent, compromising different organs and systems. Cutaneous manifestations are infrequent, being described in patients with some degree of immunosuppression. We present the case of an immunocompetent patient who developed a reactive purpura due to chronic Strongyloides stercoralis infection. Thus, skin involvement is possible in immunocompetent patients with systemic exacerbation due to this parasite.


Asunto(s)
Púrpura/etiología , Púrpura/inmunología , Estrongiloidiasis/complicaciones , Estrongiloidiasis/inmunología , Adulto , Animales , Antiparasitarios/clasificación , Antiparasitarios/uso terapéutico , Antipruriginosos/uso terapéutico , Clorfeniramina/uso terapéutico , Humanos , Huésped Inmunocomprometido , Ivermectina/uso terapéutico , Masculino , Púrpura/tratamiento farmacológico , Strongyloides stercoralis/aislamiento & purificación , Adulto Joven
13.
Rev Peru Med Exp Salud Publica ; 35(2): 326-332, 2018.
Artículo en Español | MEDLINE | ID: mdl-30183909

RESUMEN

Infections caused by rare micro-organisms are the subject of research, as researchers are encouraged to find the necessary health measures to prevent and treat the disease, as well as the search for new insights into human-microbial interactions. This report describes the case of a newborn boy diagnosed with hydrocephalus and myelomeningocele who developed ventriculitis and sepsis from resistant Empedobacter brevis. This case highlights the unexpected identification of this bacterium in the cerebrospinal fluid and its multi-resistant pattern, which was crucial for proper therapeutic management. This bacterium shows a mixture of different etiologies in the analysis of cerebrospinal fluid.


Las infecciones causadas por microorganismos poco comunes son objeto de investigación, ya que animar a los investigadores a encontrar las medidas sanitarias necesarias para prevenir y tratar la enfermedad, así como la búsqueda de nuevas luces sobre las interacciones humano-microbios. En este informe se describe el caso de un recién nacido varón diagnosticado de hidrocefalia y mielomeningocele, que desarrolló ventriculitis y sepsis por Empedobacter brevis resistente. Este caso pone de manifiesto la inesperada identificación de esta bacteria en el líquido cefalorraquídeo y su patrón multirresistente, que fue crucial para dar un manejo terapéutico adecuado. Esta bacteria evidencia una mezcla de diferentes etiologías en el análisis del líquido cefalorraquídeo.


Asunto(s)
Ventriculitis Cerebral/microbiología , Infecciones por Flavobacteriaceae , Flavobacterium , Ventriculitis Cerebral/diagnóstico , Ventriculitis Cerebral/tratamiento farmacológico , Infecciones por Flavobacteriaceae/diagnóstico , Infecciones por Flavobacteriaceae/tratamiento farmacológico , Humanos , Recién Nacido , Masculino , Perú
14.
Rev. chil. infectol ; Rev. chil. infectol;35(4): 445-447, ago. 2018. graf
Artículo en Español | LILACS | ID: biblio-978056

RESUMEN

Resumen La infección por Strongyloides stercoralis es una parasitosis frecuente en las regiones tropicales y subtropicales, incluyendo la Amazonía peruana. En pacientes con inmunocompromiso, las manifestaciones clínicas son variadas y es frecuente la diseminación sistémica de la enfermedad, con compromiso de diversos órganos. Las manifestaciones cutáneas son infrecuentes y se describen en pacientes con algún grado de inmunosupresión. Se presenta el caso de un paciente inmunocompetente que desarrolló una púrpura reactiva por una infección por Strongyloides stercoralis crónica. Ante ello, es posible el compromiso cutáneo en pacientes inmunocompetentes con reagudización sistémica por este parásito.


Infection with Strongyloides stercoralis is a common parasitic infection in tropical and subtropical regions, including the Peruvian Amazon. The clinical manifestations are varied in patients with immunocompromised disease, and the systemic spread of the disease is frequent, compromising different organs and systems. Cutaneous manifestations are infrequent, being described in patients with some degree of immunosuppression. We present the case of an immunocompetent patient who developed a reactive purpura due to chronic Strongyloides stercoralis infection. Thus, skin involvement is possible in immunocompetent patients with systemic exacerbation due to this parasite.


Asunto(s)
Humanos , Animales , Masculino , Adulto , Adulto Joven , Púrpura/etiología , Púrpura/inmunología , Estrongiloidiasis/complicaciones , Estrongiloidiasis/inmunología , Púrpura/tratamiento farmacológico , Ivermectina/uso terapéutico , Clorfeniramina/uso terapéutico , Huésped Inmunocomprometido , Strongyloides stercoralis/aislamiento & purificación , Antiparasitarios/clasificación , Antiparasitarios/uso terapéutico , Antipruriginosos/uso terapéutico
15.
Rev. peru. med. exp. salud publica ; 35(2): 326-332, abr.-jun. 2018. tab, graf
Artículo en Español | LILACS | ID: biblio-961870

RESUMEN

RESUMEN Las infecciones causadas por microorganismos poco comunes son objeto de investigación, ya que animar a los investigadores a encontrar las medidas sanitarias necesarias para prevenir y tratar la enfermedad, así como la búsqueda de nuevas luces sobre las interacciones humano-microbios. En este informe se describe el caso de un recién nacido varón diagnosticado de hidrocefalia y mielomeningocele, que desarrolló ventriculitis y sepsis por Empedobacter brevis resistente. Este caso pone de manifiesto la inesperada identificación de esta bacteria en el líquido cefalorraquídeo y su patrón multirresistente, que fue crucial para dar un manejo terapéutico adecuado. Esta bacteria evidencia una mezcla de diferentes etiologías en el análisis del líquido cefalorraquídeo.


ABSTRACT Infections caused by rare micro-organisms are the subject of research, as researchers are encouraged to find the necessary health measures to prevent and treat the disease, as well as the search for new insights into human-microbial interactions. This report describes the case of a newborn boy diagnosed with hydrocephalus and myelomeningocele who developed ventriculitis and sepsis from resistant Empedobacter brevis. This case highlights the unexpected identification of this bacterium in the cerebrospinal fluid and its multi-resistant pattern, which was crucial for proper therapeutic management. This bacterium shows a mixture of different etiologies in the analysis of cerebrospinal fluid.


Asunto(s)
Humanos , Recién Nacido , Masculino , Flavobacterium , Infecciones por Flavobacteriaceae , Ventriculitis Cerebral/microbiología , Perú , Infecciones por Flavobacteriaceae/diagnóstico , Infecciones por Flavobacteriaceae/tratamiento farmacológico , Ventriculitis Cerebral/diagnóstico , Ventriculitis Cerebral/tratamiento farmacológico
16.
Rev. argent. neurocir ; 29(4): 164-167, nov. 2015. ilus
Artículo en Español | LILACS | ID: biblio-996555

RESUMEN

El Dispositivo de Embolización Pipeline (PED) fue el primer dispositivo para la desviación de flujo aprobado por la FDA (Food and Drug Administration), el cual se emplea como tratamiento de aneurismas intracraneales. Se presenta el caso de un paciente femenino de 74 años de edad con diagnóstico de aneurisma sacular de la bifurcación de la arteria carótida interna derecha más placa calcificada en el origen de la arteria carótida interna derecha. Se decide terapia endovascular más colocación de PED como método terapéutico


The Pipeline Embolization Device (PED) was the first device for flow diversion approved by the FDA (Food and Drug Administration), which is used as a treatment of intracranial aneurysms. The case arises from a 74-year-old female patient with a diagnosis of a saccular aneurism in the right internal carotid artery bifurcation and a calcified plaque in the origin of the right internal carotid artery. The therapeutic method was decided to be endovascular therapy and PED placement


Asunto(s)
Humanos , Aneurisma Intracraneal , Embolización Terapéutica , Procedimientos Endovasculares
17.
PLoS One ; 8(12): e81976, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24349165

RESUMEN

Digital fingerprinting is a technique that consists of inserting the ID of an authorized user in the digital content that he requests. This technique has been mainly used to trace back pirate copies of multimedia content such as images, audio, and video. This study proposes the use of state-of-the-art digital fingerprinting techniques in the context of restricted distribution of digital documents. In particular, the system proposed by Kuribayashi for multimedia content is investigated. Extensive simulations show the robustness of the proposed system against average collusion attack. Perceptual transparency of the fingerprinted documents is also studied. Moreover, by using an efficient Fast Fourier Transform core and standard computer machines it is shown that the proposed system is suitable for real-world scenarios.


Asunto(s)
Algoritmos , Seguridad Computacional , Compresión de Datos/métodos , Reconocimiento de Normas Patrones Automatizadas , Análisis de Fourier , Humanos , Procesamiento de Señales Asistido por Computador
18.
An. Fac. Med. (Perú) ; 74(4): 279-283, oct.-dic. 2013. ilus, tab
Artículo en Español | LILACS-Express | LILACS, LIPECS | ID: lil-702446

RESUMEN

Objetivos: Determinar el efecto de los extractos acuoso e hidroetanólico de las hojas de Bixa orellana sobre los indicadores no enzimáticos de hepatotoxicidad, en ratas sometidas a paracetamol. Diseño: Experimental. Institución: Centro de Investigación de Bioquímica y Nutrición, Universidad Nacional Mayor de San Marcos, Lima, Perú. Material biológico: Ratas machos de 3 meses de edad. Intervenciones: Se distribuyó aleatoriamente 35 ratas machos de 3 meses de edad en 5 grupos, que recibieron vía peroral por 10 días: NaCl 0,9% los controles positivo y negativo, silimarina 300 mg/kg, extracto acuoso 500 mg/kg y extracto hidroetanólico 500 mg/kg. Previo ayuno de 24 horas, al quinto día se administró paracetamol (400 mg/kg) peroral, excepto al control negativo. Bajo anestesia con éter, se realizó punción cardiaca para extraer sangre. Principales medidas de resultados: Ratio hepático (peso hígado/peso animal x 100), bilirrubina total (BT), directa (BD) e indirecta (BI), hepatomegalia, especies reactivas al ácido tiobarbitúrico (TBARS) en hígado y suero. Resultados: El tratamiento con extracto acuoso solo disminuyó los indicadores BT y BI (p<0,01), TBARS en suero (p<0,05) y hubo disminución de la masa hepática de -13,2% (p<0,01). En el grupo que recibió el extracto hidroetanólico se redujo la BT, BI (p<0,01), BD (p<0,05), TBARS en hígado (p<0,01) y la masa hepática -9,37%. Conclusiones: Los extractos acuoso e hidroetanólico de hojas de Bixa orellana (achiote) presentarían efecto hepatoprotector frente al paracetamol a dosis tóxica, en ratas.


Objectives: To determine the effect of Bixa orellana leaves aqueous and hydroethanolic extracts on non-enzymatic indicators of hepatotoxicity in rats subjected to acetaminophen. Design: Experimental. Setting: Research Center of Biochemistry and Nutrition, Universidad Nacional Mayor de San Marcos, Lima, Peru. Biologic material: Thirty-five male rats aged 3 months. Interventions: Rats were randomized into 5 groups that received orally and for 10 days: positive and negative controls NaCl 0.9%, silymarin 300 mg/kg, aqueous extract 500 mg/kg and hydroethanolic extract 500 mg/kg; after fasting 24 hours, paracetamol 400 mg/kg peroral was administered at the fifth day, except for the negative control. Under ether anesthesia cardiac puncture was performed to obtain blood. Main outcome measures: Liver ratio (liver weight/animal weight x 100), total bilirubin (TB), direct (BD) and indirect (BI) bilirubin, hepatomegaly, thiobarbituric acid reactive species (TBARS) in liver and serum. Results: Treatment with aqueous extract alone decreased the following indicators: BT and BI (p<0.01), serum TBARS (p<0.05), hepatomegaly -13.2% (p<0.01). The group receiving hydroethanolic extract reduced BT, BI (p<0.01), BD (p<0.05), TBARS in liver (p<0.01), hepatomegaly -9.37%. Conclusions: Bixa orellana (achiote) leaves aqueous and hydroethanolic extracts showed hepatoprotective effect against paracetamol in toxic doses in rats.

19.
An. Fac. Med. (Perú) ; 70(3): 186-192, jul.-set. 2009. tab, graf
Artículo en Español | LILACS, LIPECS | ID: lil-609561

RESUMEN

Objetivo: determinar la respuesta del sistema antioxidante en varones sanos, frente a la hiperglicemia aguda inducida. Diseño: estudio prospectivo, descriptivo, longitudinal, experimental. Lugar: Instituto Nacional de Biología Andina, Facultad de Medicina, Universidad Nacional Mayor de San Marcos, Lima, Perú. Material biológico: Sangre y suero de sujetos aparentemente sanos. Intervenciones: A 13 sujetos adultos clínicamente sanos, entre 20 y 41años, después de 10 horas de ayuno, se administró glucosa vía endovenosa, mediante el método de clamp hiperglicémico, a 125 mg/dL por encima del valor basal, durante 120 minutos. Se realizó mediciones de la glicemia a 0, 5, 10, 15, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110 y 120 minutos. Se tomó la muestra sanguínea con anticoagulante EDTA y otra de sangre total, para obtención de suero, para las pruebas bioquímicas a los 0, 60 y 120 minutos. Principales medidas de resultados: Modificaciones de la glicemia y lipoperoxidación en suero, glutatión y actividad superóxido dismutasa en glóbulos rojos lisados e índices de estrés oxidativo. Resultados: El nivel de glucosa durante el clamp hiperglicémico, luego de alcanzar el æequilibrioÆ, fue 197±17,58 mg/dL. La lipoperoxidación aumentó de 2,54 + 0,51 a 2,90 + 0,58 umol/L, de 0 a 60 minutos, y a 2,66 + 0,55 umol/L a los 120 minutos. El glutatión se redujo en 8,10 por ciento a la hora, aumentando 7,08 por ciento a los 120 minutos. La actividad superóxido dismutasa se elevó 0,54 por ciento a los 60 minutos y 5,66 por ciento a los 120 minutos, sobre el basal. Los índices de valoración del estrés oxidativo tuvieron correlación r Pearson positiva, en nivel alto a muy alto. Conclusiones: la hiperglicemia aguda inducida hasta 2 horas elevó el estrés oxidativo, promoviendo generación de defensa antioxidante, con síntesis de glutatión reducido de novo y mayor actividad de la superóxido dismutasa.


Objective: To determine healthy malesÆ antioxidant system response in induced acute hyperglycemia. Design: Prospective, descriptive, longitudinal, experimental study. Setting: National Institute of Andean Biology, Faculty of Medicine, Universidad Nacional Mayor de San Marcos, Lima, Peru. Biological materials: Whole blood and serum of apparently healthy men. Interventions: After 10 hour fasting, intravenous glucose was administered to thirteen healthy 20-41 year-old adult men using the hyperglycemic clamp method at 125 mg/dL above basal value during 120 minutes. Glycemia was measured at 0, 5, 10, 15, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, and 120 minutes. Blood sampling was obtained with EDTA anticoagulant and whole blood to obtain blood serum for biochemistry tests at 0, 60 and 120 minutes. Main outcome measures: Blood serum glycemia and lipoperoxidation variation, glutathione and superoxide dismutase activity in lysed red blood cells and oxidative stress index. Results: After achieving æbalanceÆ, glucose levels during hyperglycemic clamp was 197 ± 17,58 mg/dL. Lipoperoxidation increased from 2,54 + 0,51 to 2,90 + 0,58umol/L, from 0 to 60 minutes, and to 2,66 + 0,55 umol/L at 120 minutes. Glutathione was reduced in 8,10 per cent at one hour, rising 7,08 per cent at 120 minutes. Superoxide dismutase activity rose above basal 0,54 per cent at 60 min and 5,66 per cent at 120 min. Oxidative stress valuation index had high level to very high level positive Pearson r correlation. Conclusions: Acute induced hyperglycemia up to 2 hours increased oxidative stress, promoting generation of antioxidant defence with de novo synthesis of reduced glutathione and greater activity of superoxide dismutase.


Asunto(s)
Humanos , Estrés Oxidativo , Glutatión , Peroxidación de Lípido , Superóxido Dismutasa , Técnica de Clampeo de la Glucosa , Epidemiología Descriptiva , Ensayo Clínico , Estudios Longitudinales , Estudios Prospectivos
20.
An. Fac. Med. (Perú) ; 70(2): 97-102, abr.-jun. 2009. ilus, tab
Artículo en Español | LILACS, LIPECS | ID: lil-564559

RESUMEN

Objetivo: Identificar los metabolitos secundarios presentes en el extracto hojas de Bixa orellana, evaluar el grado de protección del extracto frente a la injuria con etanol y estudio histopatológico de la región glandular del estómago. Diseño: Estudio prospectivo experimental. Institución: Centro de Investigación de Bioquímicay Nutrición Alberto Guzmán Barrón, Facultad de Medicina, Universidad Nacional Mayor de San Marcos. Material biológico: Extracto de hojas de Bixa orellana y ratas albinas machos adultos. Intervenciones: Se analizó los metabolitos secundarios del extracto, mediante los reactivos específicos. Para la evaluación del efecto antiulceroso, se aplicó la técnica propuesta por Robert 1979, a dosis de extracto de 200 y 400mg/kg. Se provocó la injuria con alcohol al 96 por ciento. La evaluación macroscópica fue mediante la escala de Marhuenda. Los tejidos fueron conservados en formol al 10 por ciento, para su estudio histopatológico por tinción hematoxilina-eosina. Principales medidas de resultados: Inhibición de las lesiones gástricas. Resultados: El extracto hidroalcohólico de hojas de Bixa orellana tiene compuestos fenólicos, tales como flavonoides y taninos, terpenos y alcaloides. El tratamiento con el extracto produjo una inhibición de las lesiones gástricas en 21,7 por ciento y 28,3 por ciento, respectivamente (p menor que 0,01). En el estudio histológico, se encontró mayor protección y menor migración de células proinflamatorias en los grupos que recibieron el extracto a 200 y 400 mg/kg. Sin embargo, los grupos controles y los que recibieron ranitidina presentaron grados de lesión considerable y un mayor incremento de migración de células proinflamatorias.Conclusiones: El extracto hidroalcohólico de Bixa orellana presenta un efecto gastroprotector antiulceroso frente a la injuria con etanol al 96 por ciento, tanto a nivelmacroscópico como microscópico.


Objective: To identify the secondary metabolites present in Bixa orellanaleaves extract, to evaluate the extract protection against ethanol injury, andhistopathology study of the stomach glandular region. Design: Prospective,experimental and analytical research. Setting: Biochemistry and NutritionResearch Center laboratories, Universidad Nacional Mayor de San Marcos. Biological material: Bixa orellana leaves extract and male albino rats. Interventions: Secondary metabolites from the extract were analyzed using identification chemical tests. For evaluation of the gastro-protective effect proposed by Robert 1979 the extract was used at 200 and 400 mg/kg doses, and for macroscopic evaluation Marhuenda scale was employed. Tissues were preserved in 10 per cent formaldehyde for histopathology examination by hematoxylineosin staining. Main outcome measures: Gastric lesions inhibition. Results: Bixa orellana leaves hydroalcoholic extract has phenolic compounds such as flavonoids and tannins, terpenes and alkaloids. Treatment with 200 and 400 mg/kg extract doses produced gastric lesions inhibition in respectively 21,7 per centand 28,3 per cent (p minor that 0,01). By histology, there was bigger protection and reduced migration of proinflammatory cells in the groups receiving 200 and 400 mg/kgextract. Control groups and those receiving ranitidine showed considerablelesion degrees and increased proinflammatory cells migration. Conclusions: Bixa orellana leaves hydroalcoholic extract produced gastroprotective effect againstinjury with 96 per cent ethanol at both macroscopic and microscopic levels.


Asunto(s)
Animales , Ratas , Antiulcerosos , Bixa orellana , Gastritis , Úlcera Gástrica
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