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The growing need for biomedical contrast agents has led to the current development of multi-functional materials such as lanthanide-based nanoparticles (NPs). The optical and magnetic properties these nanoparticles (NPs) possess are important to enhance current biomedical imaging techniques. To increase the optical emissions of the nanoparticles, neodymium (Nd3+) and ytterbium (Yb3+) were introduced into a magnetic host of NaGdF4. The energy transfer between Nd3+ and the Yb3+ was then investigated at multiple concentrations to determine the optimal dopant levels. The NaGdF4:Nd3+,Yb3+ nanoparticles were synthesized through a modified solvothermal method, resulting in rectangular structures, with an average side length of 17.87 ± 4.38 nm. A double dopant concentration of 10% Nd3+ and 4% Yb3+ was found to be optimal, increasing the emission intensity by 71.5% when compared to the widely used Nd3+ single dopant. Decay measurements confirm energy transfer from Nd3+ to Yb3+, with a lifetime shortening from Nd3+ 1064 nm emission and a calculated lifetime of 12.72 ms with 98% efficiency. Despite NaGdF4:Nd3+,Yb3+ NPs showing a slight decrease in their magnetic response at the expense of optimizing optical emission, as it is directly dependent on the Gd3+ concentration, a strong paramagnetic behavior was still observed. These results corroborate that NaGdF4:Nd3+,Yb3+ NPs are viable candidates for multimodal imaging.
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The emergence of drug-resistant superbugs remains a major burden to society. As the mortality rate caused by sepsis due to superbugs is more than 40%, accurate identification of blood infections during the early stage will have a huge significance in the clinical setting. Here, we report the synthesis of red/blue fluorescent carbon dot (CD)-attached magnetic nanoparticle-based multicolor multifunctional CD-based nanosystems, which can be used for selective separation and identification of superbugs from infected blood samples. The reported data show that multifunctional fluorescent magneto-CD nanoparticles are capable of isolating Methicillin-resistant Staphylococcus aureus (MRSA) and Salmonella DT104 superbug from whole blood samples, followed by accurate identification via multicolor fluorescence imaging. As multidrug-resistant (MDR) superbugs are resistant to antibiotics available in the market, this article also reports the design of antimicrobial peptide-conjugated multicolor fluorescent magneto-CDs for effective separation, accurate identification, and complete disinfection of MDR superbugs from infected blood. The reported data demonstrate that by combining pardaxin antimicrobial peptides, magnetic nanoparticles, and multicolor fluorescent CDs into a single system, multifunctional CDs represent a novel material for efficient separation, differentiation, and eradication of superbugs. This material shows great promise for use in clinical settings.
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This project aims to provide an insight on the effects of biocompatible polymers on the optical properties and the nanoparticle-cell interaction of KYb2F7:Tm(3+) nanocrystals that exhibit strong near infrared (NIR) fluorescence. KYb2F7:Tm(3+) nanocrystals were synthesized with a diameter of 20-30 nm and surface modified with poly(ethylene glycol), Pluronic(®) F-127, and poly(N-vinylpyrrolidone), due to the associated advantages. Some of these include biocompatibility and biodistribution in the instance of agglomeration and hydrophobicity as well as the addition of a targeting agent and drug loading by further functionalization. Despite the decrease in fluorescence intensity induced by the surface modification, thulium's emission fingerprint was easily detected. Moreover, surface modified KYb2F7:Tm(3+) nanocrystals failed to induce a toxic response on endothelial cells following a 24 h uptake period up to concentrations of 100 µg ml(-1). In vitro toxicity and confocal imaging have demonstrated the versatility of these NIR fluorescence nanocrystals in biomedical imaging, drug delivery, and photodynamic therapy.
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Nanopartículas , Sistemas de Liberação de Medicamentos , Polietilenoglicóis , Propriedades de Superfície , Túlio , Distribuição TecidualRESUMO
Introducción: La espectroscopia de impedancia eléctrica (EIE) es una técnica fácil de usar y de bajo costo que se puede utilizar para analizar tejidos biológicos en condiciones normales o patológicas. El objetivo de este trabajo fue caracterizar neoplasias de glándula mamaria benignas y malignas aplicando la técnica EIE en muestras extraídas de 45 caninos hembras (Canis lupus familiaris). Métodos: Se utilizó un medidor de impedancia eléctrica, Hioki 3532-50, para determinar los parámetros bioeléctricos: resistencia de la matriz extracelular (R), resistencia de la matriz intracelular (S), frecuencia característica (Fc) y capacitancia de membrana (Cm) en un rango de frecuencias entre 42 Hz y 5 MHz y se analizaron estadísticamente mediante la prueba no paramétrica U de Mann-Whitney (Wilcoxon) de dos colas. La precisión diagnóstica de la EIE se efectuó a través de curvas características de operación del receptor (COR) y tablas de doble entrada, con la histopatología como referencia. Resultados: Se encontraron diferencias estadísticamente significativas entre el tejido mamario sano y las neoplasias benignas para los parámetros R, Fc y Cm, p-value < 0,05. Entre tejido mamario sano y neoplasias mamarias malignas se encontraron diferencias estadísticamente significativas para R y Fc con un p-value < 0,05. La comparación entre lesiones tumorales benignas y malignas no presentó diferencias estadísticamente significativas, p-value > 0,05, para ninguna de las variables incluidas en este estudio. Conclusiones: De los parámetros analizados por EIE, la resistencia de la matriz extracelular es la que mejor permite diferenciar entre tejidos mamarios normales y neoplásicos. La EIE es una herramienta diagnóstica potencial que puede ser utilizada en la detección de cáncer mamario, con una precisión diagnóstica cercana al 80%.
Introduction: Electrical Impedance Spectroscopy (EIS) it is an easy to use and low-cost technique that can be used to analyze biological tissues in normal or pathological condition. The goal of this work was to characterize benign and malign mammary gland neoplasms applying the EIS technique in 45 female dogs (Canis lupus familiaris). Methods: An impedance meter Hioki 3532-50 was used to determine bioelectric parameters, extracellular matrix resistance (R), intracellular matrix resistance (S), characteristic frequency (Cf), and membrane capacitance (Mc), which were obtained in a 42 Hz and 5 MHz frequencies range. Were statistically analyzed with the non-parametric test of two-tailed MannWhitney (Wilcoxon). The diagnostic precision of the test was performed using receiver operating characteristics (ROC) and two-way tables using histopathology results as reference. Results: Significant differences between healthy mammary tissue and benign neoplasms were found for variables R, Cf and Mc (p < 0.05). There were statistically major differences between the healthy mammary tissue and malign mammary tumors groups for R and Cf (p < 0.05). The comparison between malign and benign tumor lesions did not show a statistically significant difference, p-value > 0.05, for any of the variables included in this study. Conclusion: Among all parameters analyzed for EIS, the extracellular matrix resistance R is the one that best allows differentiating between healthy and neoplastic mammary tissues. EIS is a diagnostic tool that can be used for breast cancer detection with a diagnostic precision close to 801%.
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Research has found a strong inverse association between discrimination and health and well-being. Most of these studies have been conducted among African-Americans, and have examined the relationship at the individual-level. To fill these gaps in knowledge we estimated the prevalence of perceived discrimination among a nationally representative sample of Latino adults in the US, and investigated the association between state-level anti-immigrant policies and perceived discrimination. We merged survey data with a state-level anti-immigrant policy index. First, we fit hierarchical logistic regression models to test the crude and adjusted association between anti-immigrant policies and perceived discrimination. Second, we specified cross-level interaction terms to test whether this association differed by relevant individual characteristics. Almost 70% of respondents reported discrimination (68.4%). More anti-immigrant policies were associated with higher levels of discrimination (OR=1.62, 95% CI 1.16, 2.24, p=0.01). The association between anti-immigrant policies and discrimination differed by place of origin (p=0.001) and was marginally moderated by generation status (p=0.124). Anti-immigrant policies stigmatize both foreign and US-born Latinos by creating a hostile social environment which affects their experiences of discrimination. These non-health policies can adversely affect Latino health, in part through exposure to discrimination, and may help explain health patterns among Latinos in the US.
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More than a billion people lack access to safe drinking water that is free from pathogenic bacteria and toxic metals. The World Health Organization estimates several million people, mostly children, die every year due to the lack of good quality water. Driven by this need, we report the development of PGLa antimicrobial peptide and glutathione conjugated carbon nanotube (CNT) bridged three-dimensional (3D) porous graphene oxide membrane, which can be used for highly efficient disinfection of Escherichia coli O157:H7 bacteria and removal of As(III), As(V), and Pb(II) from water. Reported results demonstrate that versatile membrane has the capability to capture and completely disinfect pathogenic pathogenic E. coli O157:H7 bacteria from water. Experimentally observed disinfection data indicate that the PGLa attached membrane can dramatically enhance the possibility of destroying pathogenic E. coli bacteria via synergistic mechanism. Reported results show that glutathione attached CNT-bridged 3D graphene oxide membrane can be used to remove As(III), As(V), and Pb(II) from water sample at 10 ppm level. Our data demonstrated that PGLa and glutathione attached membrane has the capability for high efficient removal of E. coli O157:H7 bacteria, As(III), As(V), and Pb(II) simultaneously from Mississippi River water.
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Desinfecção/métodos , Escherichia coli O157/isolamento & purificação , Grafite/química , Membranas Artificiais , Metais Pesados/isolamento & purificação , Nanotubos de Carbono/química , Óxidos/química , Purificação da Água/métodos , Peptídeos Catiônicos Antimicrobianos , Glutationa/química , Porosidade , Reação em Cadeia da Polimerase em Tempo Real , Rios/químicaRESUMO
According to the World Health Organization (WHO), multiple drug-resistant (MDR) bacterial infection is a top threat to human health. Since bacteria evolve to resist antibiotics faster than scientists can develop new classes of drugs, the development of new materials which can be used, not only for separation, but also for effective disinfection of drug resistant pathogens is urgent. Driven by this need, we report for the first time the development of a nisin antimicrobial peptide conjugated, three dimensional (3D) porous graphene oxide membrane for identification, effective separation, and complete disinfection of MDR methicillin-resistant Staphylococcus aureus (MRSA) pathogens from water. Experimental data show that due to the size differences, MRSA is captured by the porous membrane, allowing only water to pass through. SEM, TEM, and fluorescence images confirm that pathogens are captured by the membrane. RT-PCR data with colony counting indicate that almost 100% of MRSA can be removed and destroyed from the water sample using the developed membrane. Comparison of MDR killing data between nisin alone, the graphene oxide membrane and the nisin attached graphene oxide membrane demonstrate that the nisin antimicrobial peptide attached graphene oxide membrane can dramatically enhance the possibility of destroying MRSA via a synergestic effect due to the multimodal mechanism.
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Circulating tumor cells (CTCs) are extremely rare cells in blood containing billions of other cells. The selective capture and identification of rare cells with sufficient sensitivity is a real challenge. Driven by this need, this manuscript reports the development of a multifunctional biocompatible graphene oxide quantum dots (GOQDs) coated, high-luminescence magnetic nanoplatform for the selective separation and diagnosis of Glypican-3 (GPC3)-expressed Hep G2 liver cancer tumor CTCs from infected blood. Experimental data show that an anti-GPC3-antibody-attached multifunctional nanoplatform can be used for selective Hep G2 hepatocellular carcinoma tumor cell separation from infected blood containing 10 tumor cells/mL of blood in a 15 mL sample. Reported data indicate that, because of an extremely high two-photon absorption cross section (40530 GM), an anti-GPC3-antibody-attached GOQDs-coated magnetic nanoplatform can be used as a two-photon luminescence platform for selective and very bright imaging of a Hep G2 tumor cell in a biological transparency window using 960 nm light. Experimental results with nontargeted GPC3(-) and SK-BR-3 breast cancer cells show that multifunctional-nanoplatform-based cell separation, followed by two-photon imaging, is highly selective for Hep G2 hepatocellular carcinoma tumor cells.
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Materiais Biocompatíveis/síntese química , Grafite/química , Nanopartículas de Magnetita/química , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Células Neoplásicas Circulantes/patologia , Pontos Quânticos , Células Hep G2 , Humanos , Nanopartículas de Magnetita/ultraestrutura , Teste de Materiais , Nanoconjugados/química , Nanoconjugados/ultraestrutura , Óxidos/química , Tamanho da Partícula , Doenças Raras/patologia , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Nanoparticles are presently being studied for optical and biomedical applications such as medical imaging and drug delivery. Nanoparticles impact the cellular environment due to many variables such as size, shape, and composition. How these factors affect cell viability is not fully understood. The purpose of this study is to test the toxicity effects of silver coating (Ag@) Barium Titanium Oxide (BaTiO3) nanoparticles on Rhesus Monkey Retinal Endothelial cells (RhREC's) in culture. The addition of silver to the nanoparticles increases their nonlinear optical properties significantly, making the Ag@BaTiO3 nanoparticles good candidates for nonlinear microscopy contrast agents. We hypothesize that by silver coating nanoparticles, there will be an increase in cell viability at higher concentrations when compared to non-silver coated nanoparticles. RhREC's were treated with BaTiO3 and Ag@BaTiO3 at concentrations of 0, 1.0, 10.0, and 100µg/ml for 24 hours at 37°C + 5%CO2. After 24 hour incubation with respective nanoparticles, cell viability was determined using the trypan blue dye-exclusion method. Treatment with 0, 1.0 and 10.0µg/ml of Ag@BaTiO3 had minimal effect on cell viability, with 90% viable cells remaining at the end of the 24 hours treatment period. However, cells treated with 100µg/ml of Ag@BaTiO3 resulted in a decrease to 51% viable cells. Comparatively, cells treated with 0, 1.0 and 10µg/ml of BaTiO3 had no significant effect on cell viability (90% viable cells after treatment) while the 100µg/ml treatment resulted in a decrease to 29% viable cells. These results show that silver coating of BaTiO3 nanoparticles has a protective effect on cellular toxicity at high concentrations.
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Here we report the synthesis, characterization and application of a multifunctional surface functionalized GdF3:Nd3+ nanophosphor that exhibits efficient near infrared (NIR) fluorescence as well as magnetic properties, which can be utilized for bimodal imaging in medical applications. The nanoparticles are small with an average size of 5 nm and form stable colloids that last for several weeks without settling, enabling the use for several biomedical and photonic applications. Their excellent NIR properties, such as nearly 11 % quantum yield of the 1064 nm emission, make them ideal contrast agents and biomarkers for in vitro and in vivo NIR optical bioimaging. The nanophosphors which were coated with poly(maleic anhydride- alt-1-octadicene) (PMAO) were implemented in cellular imaging and show no significant cellular toxicity for concentrations up to 200 µg ml-1. Furthermore, the incorporation of Gd into the nanocrystalline structure supplies exceptional magnetic properties, making them ideal for use as magnetic resonance imaging (MRI) contrast agents. The utility of these NIR emitting nanoparticles in infrared bioimaging and as contrast agent in magnetic resonance imaging was demonstrated by confocal imaging, magnetic resonance and tissue experiments.
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Barium titanate (BaTiO3) is a technologically important material because of its nonlinear properties, such as its strong second harmonic generation and high third order susceptibility. While many nonlinear effects have been extensively studied on the bulk scale, there are still questions regarding the strength of nonlinear effects in nanoparticles. The nonlinear properties of BaTiO3 nanoparticles and nanorods have been studied using the closed aperture z-scan technique. Silver was then grown photochemically on the surface of the BaTiO3 nanoparticles, and it was found that the third order susceptibility increases dramatically.
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Simulação por Computador , Luz , Nanopartículas/química , Espalhamento de Radiação , Prata/química , Ressonância de Plasmônio de Superfície/instrumentação , Humanos , Dinâmica não LinearRESUMO
Fifteen cases of viral meningoencephalitis in Colombian cattle were tested by nested PCR analysis for the detection of bovine herpesvirus 5 (BoHV-5). All fatal cases had shown severe neurological signs and had occurred following natural outbreaks of the disease. The neurological infection was histologically characterized by mild to moderate inflammatory changes in the brain and cerebellum, including meningitis, mononuclear perivascular cuffing, gliosis, haemorrhage, and the presence of Gitter cells (macrophages) accompanying large areas of malacia. No intranuclear inclusion bodies were seen in any of the cases. Results from BoHV-5 molecular extraction analyses showed there were five positive cases thus confirming the presence of the virus in Colombia.
Quince casos de meningoencefalitis viral en ganado Colombiano fueron analizados por reacción en cadena de la polimerasa (PCR anidada) para la detección del herpesvirus bovino 5 (BoHV-5). Todos los casos mostraron severos signos neurológicos antes de morir y ocurrieron como brotes naturales de la enfermedad. La infección neurológica fue caracterizada histológicamente por leves a moderados cambios inflamatorios en el cerebro y cerebelo, incluyendo meningitis, manguitos perivasculares, gliosis, hemorragia y la presencia de células Gitter (macrófagos) acompañando grandes áreas de malacia. No se encontraron cuerpos de inclusión intranucleares en ninguno de los casos. Los resultados del análisis de la extracción molecular de BoHV-5 revelaron la existencia de cinco casos positivos, lo cual confirma la presencia del virus en Colombia.
Quinze casos de meningoencefalite viral em gado bovino Colombiano foi analisado pela reação em cadeia da polimerasa (PCR) para a detecção do herpesvírus bovino 5 (BoHV-5). Todos os casos mostraram graves sinais neurológicos antes de morrer y aconteceram como surtos naturais da doença. A infecção neurológica foi caracterizada histologicamente por leves a moderados câmbios inflamatórios no cérebro e cerebelo, incluindo meningite, manguitos perivasculares, gliose, hemorragia e a presencia de células gitter (macrófagos) acompanhando grandes áreas de malacia. Não se encontraram corpos de inclusão intranucleares em nenhum dos casos. Os resultados da análise da extração molecular do BoHV-5 por PCR revelaram a existência de cinco casos positivos, os quais confirmam a presença do vírus na Colômbia.
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Los herpesvirus bovino tipo 1 y 5 (BoHV-1 y BoHV-5), causan enfermedades que producen importantespérdidas económicas en ganaderías de todo el mundo. Ambos afectan el sistema nervioso de los bovinos,aunque ha sido el BoHV-5 más asociado a este tipo de patogénesis. Teniendo en cuenta la muerte de animalescon sintomas nerviosos y negativos a rabia en la zona de estudio, el objetivo de esta investigación se centró enla detección de reactores positivos por seroneutralización al herpesvirus bovino, recolectando 518 muestrasde sangre en bovinos sin vacuna contra este agente, en los municipios de Caparrapi (Cundinamarca),Cimitarra (Santander), Honda (Tolima) y Victoria (Caldas). Además, información epidemiológica útilpara discutir sobre enfermedad neurológica fue recolectada mediante fuentes de información primariasy secundarias. Para el análisis de los datos se utilizó la prueba chi-cuadrado identificando la relaciónentre la evidencia de infección viral y las variables registradas. Los resultados revelaron que 286 casosfueron positivos a infección con herpesvirus, correspondiendo a una prevalencia de 55.5%, sin embargo,no hubo relación estadística (p<0.05) entre la presencia de anticuerpos y las variables que se analizaron.En conclusión, algunos de los casos de enfermedad neurológica en bovinos del área pudieron deberse a lainfección con los herpesvirus y se discute sobre la presencia de ellos en el medio, los planes de diagnósticoy control, así como las pérdidas económicas que puedan causar en ganaderías de la zona.
The bovine Herpesvirus type 1 and type 5 (BoHV-1 and BoHV-5), causing diseases and significanteconomic losses in farms of worldwide. Both affect the nervous system of cattle, although BoHV-5 hasbeen the most associated with this type of pathogenesis. Given the death of animals with nervous symptomsand negative diagnoses for rabies virus in the area of study, this research focused on the detection ofpositive reactors to bovine herpes virus serum neutralization. We collected 518 blood samples from animalswithout Herpesvirus vaccine, in the municipalities of Caparrapi, Cimitarra, Honda and Victoria, in theMiddle Magdalena River Region. In addition, epidemiological information useful to discuss neurologicaldisease was collected through primary and secondary sources. For the analysis of data was used chi-squaretest by identification of relationship between evidence of viral infection and the variables recorded. Theresults revealed that 286 cases were positive for Herpesvirus infection, corresponding to a prevalence of55.5%, however, there was no statistical relationship (p < 0.05) between the presence of antibodies and thevariables analyzed. In conclusion, some cases of neurological disease in cattle in this region could be dueto infection with herpes viruses. We discussed about the presence of BoHV-1 and BoHV-5 in the ambient,diagnosis and monitoring plans, as well as economic losses, which may cause in herds in this area.
Os herpesvirus bovino tipo 1 e 5 (BoHV-1 e BoHV-5), causam doenças que produzem importantesperdidas econômicas no gado de todo o mundo. Juntos afetam o sistema nervoso dos bovinos, embora temsido o BoHV-5 mais associado a este tipo de patogênese. Tinindo em conta a morte de animais com sintomasnervosos e negativos à doença da raiva na zona do estudo, objetivo-se esta pesquisa na detecção de reatorespositivos pela soro neutralização ao herpesvirus bovino, coletando 518 amostras de sangue em bovinossem vacina contra este agente, nos municípios de Caparrapi, Cimitarra, Honda e Victoria, zona conhecidacomo Magdalena Médio Colombiano. Alem disso, informação epidemiológica útil para discutir sobre adoença neurológica foi coletada mediante fontes de informação primarias e secundarias. Para o análisedos dados utilizou-se o teste Ji quadrado, identificando a relação entre a evidencia de infecção viral e asvariáveis registradas. Os resultados revelaram que 286 casos foram positivos à infecção com herpesvirus,correspondendo a uma prevalência de 55,5%, embora, não apresentou relação estadística (p<0,05) entrea presencia de anticorpos e as variáveis que se analisaram. Em conclusão, alguns dos casos de doençaneurológica em bovinos da área poderiam ter sido causados pela infecção com os herpesvirus e se discutesobre a presencia no médio, os planos de diagnóstico e controle, assim como, as perdas econômicas naregião.
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Animais , Herpesvirus Bovino 1RESUMO
Se presenta una revisión bibliográfica sobre la encefalitis bovina que causa en herpesvirus bovino tipo 5 (HVB-5) destacando aspectos relativos a las características biológicas del virus, patogénesis, signos clínicos de la enfermedad y diagnóstico. Se enfatiza en el conocimiento de algunas enfermedades como la polioencefalomalacia de los bovinos que es uno de los principales diagnósticos diferenciales de esta entidad. El HVB-5 cuya presencia ha sido reportada en varios países de Europa y América no se encuentra descrito en Colombia por lo que se discute sobre la existencia del mismo y la necesidad de investigación al respecto en el país.
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Bovinos , Encefalomalacia , Encefalite Viral/veterinária , Herpesvirus Bovino 5RESUMO
Teniendo en cuenta que la Secretaría Distrital de Salud contrata las actividades de promoción y prevención con los hospitales adscritos a la misma al igual que la atención de distintas patologías, es necesario realizar un estudio de costos, que genere la información requerida para poder establecer las tarifas a las cuales se deben contratar dichas actividades, buscando un beneficio bilateral entre la Secretaría y su red adscrita. El objetivo general de esta investigación está enfocado en determinar los costos de servicios de salud de las actividades de promoción y prevención por grupo evolutivo y establecer los costos de las patologías más frecuentes atendidas en los hospitales de I, II y III nivel de la red adscrita a la Secretaría Distrital de Salud. La metodología a usar en esta investigación tiene la siguiente estructura general: 1. Estructurar las actividades de promoción y prevención1 y definir la estructura óptima de actividades que incluye cada patología2. 2 Establecer los recursos "óptimos" de las actividades de promoción y prevención por grupo evolutivo y de las que componen a cada patología. 3. Definir los factores de los costos indirectos. 4. Diseñar y realizar un modelo que permita el costeo de los servicios de salud de estas actividades. Los resultados finales de costos reflejan la situación real de los hospitales, teniendo parámetros donde se optimiza el uso de recursos, pero donde se evidencian las características de los productores, es importante tener en cuenta esta información, únicamente como referencia frente a políticas de optimización del uso de recursos, y como punto de partida en busca de eficiencia organizacional y corporativa, esto tanto para las actividades de promoción y prevención como para los costos de las patologías. Una de las principales conclusiones refleja que los hospitales adscritos a la SDS tienen en la actualidad unos costos muy altos, afectados principalmente por el factor administrativo que manejan estas instituciones sobre su producción, es decir; sobre el costo directo del servido, que de no reestructurarlos difícilmente les permitirá ser rentables o, por lo menos, económicamente sostenibles.
Taking into account that the District Health Secretariat contracts promotion and prevention activities with the hospitals attached to it, as well as the care of different pathologies, it is necessary to conduct a cost study that generates the information required to establish the rates at which these activities should be contracted, seeking a bilateral benefit between the Secretariat and its attached network. The general objective of this research is focused on determining the costs of health services of promotion and prevention activities by evolutionary group and establishing the costs of the most frequent pathologies attended in the hospitals of I, II and III level of the network assigned to the District Health Secretariat. The methodology to be used in this research has the following general structure: 1. Structure the promotion and prevention activities1 and define the optimal structure of activities that includes each pathology2. 2. 2. Establish the "optimal" resources of the promotion and prevention activities by evolutionary group and of those that make up each pathology. 3. Define the indirect cost factors. 4. Design and implement a model that allows the costing of health services for these activities. The final results of costs reflect the real situation of the hospitals, having parameters where the use of resources is optimized, but where the characteristics of the producers are evidenced, it is important to take into account this information, only as a reference against policies of optimization of the use of resources, and as a starting point in search of organizational and corporate efficiency, this both for promotion and prevention activities and for the costs of pathologies. One of the main conclusions reflects that the hospitals attached to the SDS currently have very high costs, mainly affected by the administrative factor that these institutions manage over their production, that is, over the direct cost of the service, which, if they are not restructured, will hardly allow them to be profitable or, at least, economically sustainable.