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1.
Rev. colomb. quím. (Bogotá) ; 51(1): 40-47, Jan.-Apr. 2022. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1408080

RESUMO

Resumen La actividad cafetalera en Costa Rica procesa aproximadamente 69.000 toneladas de café mediante la técnica de beneficiado húmedo. Esta actividad conlleva un alto impacto ambiental debido a la generación de8Lde agua residual/kg de café oro producido. El presente trabajo tiene como objetivo utilizar el agua residual del procesamiento de café como sustrato en celdas combustibles microbianas (CCM), con el propósito de generar energía eléctrica a través de su uso y, a la vez, disminuir la carga orgánica del residuo. La CCM empleó un cátodo modificado con ftalocianinas de hierro (FePc), generó una eficiencia coulómbica de 0,7% y una densidad de potencia de 89 UW/ cm2 en un ciclo de operación de cinco días. Además, se determinó que la CCM disminuye la demanda química de oxígeno (DQO) del residuo hasta en 27% bajo las condiciones de operación nativas del sustrato, a temperatura ambiente, sin mediadores químicos para la reacción anódica y con el uso de electrodos de platino para el cátodo. El estudio confirma la oportunidad de emplear el sustrato con una flora microbiana nativa apta para la operación de la tecnología de la CCM, y así perfilar el dispositivo como una opción novedosa para el tratamiento de este residuo en Costa Rica.


Abstract In Costa Rica coffee production is the most traditional agroindustrial activity, each year approximately 69,000 tons of coffee are processed through the technique of wet processing. The process has a high environmental impact since it generates eight liters of wastewater/kg of produced coffee. Consequently, the main goal of this research was to evaluate the electric generation of a Microbial Fuel Cell (MFC) with two chambers, using coffee wastewater as a substrate, which would generate a sustainable solution with an added economic value to this waste in Costa Rica. The MFC with a cathode modified with iron phthalocyanines (FePc) generated a coulombic efficiency of 0.7% and a power density of 89 -uW/cm2 in a 5-day operation cycle. In addition, it was determined that the MFC decreases the COD of the waste by up to 27% under native substrate conditions, without the use of high temperatures, or chemical mediators for the anodic reaction and platinum electrodes for the cathode chamber. The efficiency of the device can be improved with changes at design level that reduce the ohmic internal resistance and improve electrical generation, the study confirms the potential of the substrate with a native microorganism suitable for the use of MFC technology, shaping the device as a novelty option for the treatment of the waste in Costa Rica.


Resumo A indústria do café na Costa Rica processa cerca de 69 000 toneladas de café por meio da técnica de moagem úmida, o que acarreta um alto impacto ambiental devido à geração de 8 L de água residual / kg de café dourado. O objetivo deste trabalho era usar águas residuais do processamento do café como substrato em Células de Combustível Microbianas (CCM) a fim de gerar energia elétrica por meio do seu aproveitamento e ao mesmo tempo reduzir a carga orgânica do resíduo. CCM usando cátodo modificado com ftalocianinas de ferro (FePc) gerou uma eficiência coulômbica de 0,7% e uma densidade de potência de 89 uW/cm2 em um ciclo operacional de cinco dias. Além disso, foi determinado que o CCM reduz a Demanda Química de Oxigénio (DQO) do resíduo em até 27% nas condições nativas de operação do substrato, à temperatura ambiente, sem mediadores químicos para a reação anódica e com a utilização de eletrodos de platina para o cátodo. O estudo confirma a oportunidade de utilizar o substrato com flora microbiana nativa adequada para o funcionamento da tecnologia CCM e, assim, delinear o dispositivo como uma nova opção para o tratamento desses resíduos na Costa Rica.

2.
J Econ Entomol ; 114(3): 1159-1165, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-33822082

RESUMO

The rice water weevil, Lissorhoptrus oryzophilus Kuschel, is the most important economic pest of rice in the United States with the ability to substantially reduce rice yields. Stem borers, including the Mexican rice borer, Eoreuma loftini (Dyar), are emerging as more consistent pests in Louisiana and Texas, but the relationship between blanked panicles (whiteheads) caused by stem borer feeding and yield loss is not well understood. A series of field trials was conducted in Louisiana from 2019 to 2020 to determine the relative yield loss by manipulating infestations of both pests with selective insecticides. Results indicate losses from L. oryzophilus infestations are greater than those for E. loftini in early planted rice. In contrast, relative yield losses were approximately equal in later planted rice in 2019, in which E. loftini infestations were high. Additive impacts of the root-feeding L. oryzophilus and the stem-feeding E. loftini were not observed in our study. Linear regression revealed that each increase of one whitehead per square meter is associated with a 1.7% loss in yield. Results from ratoon rice suggest that protection from L. oryzophilus in the main crop also improves yield in the second crop. Collectively, results demonstrate the continued need for effective L. oryzophilus management programs to prevent economic losses. Conversely, findings suggest that benefits of E. loftini control may be minimal in many instances. Control of E. loftini is most likely to be economical under conditions where high populations are anticipated such as in late-planted fields or regions that previously had high infestations.


Assuntos
Besouros , Oryza , Gorgulhos , Animais , Louisiana , México , Texas , Água
3.
Neth Heart J ; 28(7-8): 424-430, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32607704

RESUMO

INTRODUCTION: A reduction in the number of interventional cardiology procedures has emerged as a result of the COVID-19 pandemic. A survey was performed to quantify this decrease and the impact on the management of myocardial infarction in Latin America. METHODS: A telematic survey was conducted for all countries in Latin America. Diagnostic catheterisations, coronary and structural interventions, as well as the incidence and delay to reperfusion therapy of myocardial infarction (STEMI), were recorded. Two periods were compared: from 24 February to 8 March 2020 (pre-COVID-19) and another 2­week period that varied according to country (COVID-19). RESULTS: Responses were obtained from 79 centres in 20 countries. There was a significant decrease in the number of diagnostic procedures (-65.2%), coronary interventions (-59.4%), structural therapeutics (-86.1%) and STEMI care (-51.2%). A decrease was noted in the incidence of STEMI, but also a delay in the time to STEMI reperfusion. While there was a variation in activity in interventional cardiology between countries, patient behaviour was rather homogeneous. CONCLUSIONS: A significant reduction in healthcare activity has been noted during the COVID-19 pandemic, including STEMI care, with the risk of increased mortality and/or morbidity following STEMI. Healthcare providers should encourage patients with suspected symptoms of STEMI to call for emergency care to ensure rapid diagnosis and timely reperfusion treatment.

4.
Clin Transl Oncol ; 22(5): 782-785, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31359339

RESUMO

INTRODUCTION: CD47 over expression has been reported in several tumor subtypes. CD47 interacts with SIRPalpha on macrophages inhibiting phagocytic signal, providing a survival advantage to tumor. CD47, therefore, represents a valuable target for immunotherapy and is currently under clinical investigation. We aimed to study CD47 expression in Hodgkin Reed Sternberg cells (HRS). METHODS: We tested a polyclonal CD47 antibody (LifeSpan Biosciences, Seattle, WA) expression along with classical HRS cell markers on a tissue array of 16 classical Hodgkin Lymphoma (CHL) tumor biopsies obtained from newly diagnosed, non-selected patients (8 Female, 8 Male patients) in our institution from October 2016 to January 2018. Histologic subtypes were nodular sclerosis in 11 cases, mixed Cellularity in 3 cases and lymphocyte rich in 2 additional cases. Median age was 53 years (Range: 8, 74). Early stage disease was found in three patients without unfavorable prognostic factors according to EORTC and GHSG criteria, one patient with unfavorable prognostic factors and nine patients had advanced disease. Bulk disease was present in one patient. Normal lymphoid tissue and normal prostate epithelium were used as normal controls as recommended by manufacturer. Approval from the Local Ethical committee was obtained before any analysis. RESULTS: CD47 was overexpressed on all HRS cells with a characteristic dot-like pattern in 13/13 cases of CHL. HRS clearly expressed CD47 more intensely than infiltrating T and stromal cells. DISCUSSION: We propose that HRS cells, by up-regulating CD47, might avoid innate immunity check on tumor growth, which could be circumvented using blocking monoclonal antibodies.


Assuntos
Antígeno CD47/metabolismo , Doença de Hodgkin/patologia , Células de Reed-Sternberg/metabolismo , Adolescente , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , Criança , Feminino , Doença de Hodgkin/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Análise Serial de Tecidos , Adulto Jovem
5.
Acta Ortop Mex ; 33(4): 241-246, 2019.
Artigo em Espanhol | MEDLINE | ID: mdl-32246595

RESUMO

INTRODUCTION: Bipolar hemiarthroplasty is an alternative for the treatment of displaced femoral neck fractures in elderly patients with low functional demand and associated comorbidities. The goal was to describe functionality in patients over 65 years of age with intracapsular fractures of the hip. MATERIAL AND METHODS: Retrospective review of patients over 65 years of age between January 2012 and May 2017. It was evaluated with the Harris Hip Score (HHS) and Oxford scale at six months and the year after surgery. Complications and mortality were documented during the first post-surgical year. RESULTS: 48 cases (12 men; 36 women), average age of 80.8 ± 7.7 years. Most common diseases: high blood pressure (77.1%), osteoporosis (37.5%), diabetes (33.3%) hypothyroidism (29.2%). The percentage of associated postoperative complications was 8.3% (four cases). The median HHS at six and 12 months was: 90.5 (DE: 77.5-96.0) and 96 (DE: 92-98), respectively. The Oxford scale was 45.5 (DE: 38.5-48.0) at six months and 47.0 (DE: 43.5-48.0) per postoperative year. 4.2% (two cases) died during the first post-surgical year and none were associated with the procedure. DISCUSSION: HA provides good functional outcomes in patients over 65 years of age, with a low rate of complications. No mortality associated with the surgical procedure was observed in our series and in the short term.


INTRODUCCIÓN: La hemiartroplastía bipolar (HA) es una alternativa para el tratamiento de las fracturas desplazadas de cuello femoral en pacientes de edad avanzada con baja demanda funcional y comorbilidades asociadas. El objetivo fue describir la funcionalidad en pacientes mayores de 65 años con fracturas intracapsulares de cadera tratados con HA. MATERIAL Y MÉTODOS: Revisión retrospectiva de pacientes mayores de 65 años entre Enero de 2012 y Mayo de 2017. Se evaluó con la escala de Harris (HHS) y Oxford a los seis meses y al año posterior a la cirugía. Se documentaron las complicaciones y la mortalidad durante el primer año postquirúrgico. RESULTADOS: 48 casos (12 hombres; 36 mujeres), edad promedio de 80.8 ± 7.7 años. Comorbilidades más frecuentes: hipertensión arterial (77.1%), osteoporosis (37.5%), diabetes (33.3%) e hipotiroidismo (29.2%). El porcentaje de complicaciones postoperatorias asociadas fue de 8.3% (cuatro casos). La mediana del HHS a los seis y 12 meses fue de: 90.5 (DE: 77.5-96.0) y 96 (DE: 92-98), respectivamente. La escala de Oxford fue de 45.5 (DE: 38.5-48.0) a los seis meses y de 47.0 (DE: 43.5-48) al año postoperatorio. El 4.2% (dos casos) fallecieron durante el primer año postquirúrgico y ninguno estuvo asociado al procedimiento. DISCUSIÓN: La HA ofrece buenos resultados funcionales en pacientes mayores de 65 años, con una tasa baja de complicaciones. En nuestra serie y en el corto plazo no se observó mortalidad asociada al procedimiento quirúrgico.


Assuntos
Artroplastia de Quadril , Fraturas do Colo Femoral , Hemiartroplastia , Fraturas do Quadril , Idoso , Idoso de 80 Anos ou mais , Feminino , Hemiartroplastia/métodos , Fraturas do Quadril/cirurgia , Humanos , Masculino , Estudos Retrospectivos , Resultado do Tratamento
6.
Plant Biol (Stuttg) ; 20(6): 1042-1052, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30055073

RESUMO

Germination responses of non-dormant seeds to temperature and thermal requirements are affected by the geoclimatic origin of the species, along with specific attributes such as life form, life cycle or seed size. We evaluated the relationship of these attributes and temperature to germination in 18 species that inhabit a convergence area of two biogeographic realms. Seeds were sown at different constant temperatures. Base temperature (Tb ) and thermal time for 50% germination (θT(50) ) were determined. For Tb , θT(50) and seed size, we performed a cluster analysis and then applied a discriminant analysis (DA). DA was also performed using geoclimatic origin, life form and life cycle as grouping variables. Seed that did not germinate were transferred to the benefit temperature for germination. Finally, ethylene was applied to the remaining seeds that did not germinate. Temperature significantly affected final germination. Tb varied between 5 and 13 °C in 15 species and 19.0-21.5 °C in the remainder; θT(50) was 7-30 °Cd in eight species and 50-109 °Cd in the remainder. Cluster analysis showed three groups, and DA evidenced the relevance of Tb and θT(50) for this separation. Differences in life cycle were related to θT(50) . The geoclimatic origin was not significant. Thermoinhibition or thermodormancy were found in some species. Tb overlaps with environmental temperature of the growth season. Thermal traits for germination mainly reflect the species' life cycle, which is related to the main differences in reproductive performance among annuals and perennials. Local adaptation might mask the effect of geoclimatic origin of a species.


Assuntos
Germinação/fisiologia , México , Dormência de Plantas/fisiologia , Fenômenos Fisiológicos Vegetais , Sementes/anatomia & histologia , Sementes/fisiologia , Temperatura , Fatores de Tempo
7.
Transplant Proc ; 50(2): 485-492, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29579833

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is the most frequent primary malignant liver tumor, with the Milan criteria considered to be the gold standard for patient selection for liver transplantation (LT). MATERIALS AND METHODS: We performed a descriptive observational study, reviewing 20 years of experience of LT in patients with HCC in the Fundacion Valle del Lilí in Cali, Colombia. Subgroup analysis was undertaken for periods 1999 to 2007 and 2008 to 2015. RESULTS: Fifty-seven cases with a pretransplant HCC diagnosis were reviewed. In the first period patients within the Milan criteria had a recurrence-free survival at 5 years of 66.6%, and in those who exceeded the Milan criteria, recurrence-free survival was 75%. In the second period, patients within the Milan criteria, recurrence-free survival at 5 years was 93.5%, and in those who exceeded the Milan criteria, recurrence-free survival was 75.7%. No statistically significant difference was found in either period. For patients with mild and moderate tumor differentiation, the relapse survival rate at 5 years was 69.4% (95% confidence interval [CI] 35.8-87.8) and 74.7% (95% CI 44.5-90), respectively. All patients with poor tumor differentiation relapsed and died within 3 years. CONCLUSION: Global and recurrence-free survival among patients who met and patients who exceeded the Milan criteria was not significantly different, suggesting an expansion of the Milan criteria to include potential recipients who were previously excluded. Obtaining histologic differentiation and identifying vascular invasion will provide a more worthwhile contribution to LT decision making.


Assuntos
Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado/mortalidade , Adulto , Idoso , Colômbia/epidemiologia , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/patologia , Seleção de Pacientes
8.
Transplant Proc ; 50(2): 493-498, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29579834

RESUMO

BACKGROUND: Around 2.4% of the world's population is infected with hepatitis C virus (HCV), and it is the most common cause of liver transplantation (LT) in the world. Latin America (LA), with nearly 9% of the world population, has had a continuous increase in the number of LTs per year. Yet, due to the lack of mandatory data collection and a well-developed health-care system, access to transplantation is limited in most LA countries. We report the first LA experience of HCV-infected LT patients. METHODS: We performed a retrospective cohort study by reviewing the medical histories of all HCV-infected LT patients between 1996 and 2016 who acquired HCV before their LT, at the Fundación Valle del Lilí, Cali, Colombia. RESULTS: Between January 1996 and December 2015, a total of 770 LTs were performed, of which 75 had a cirrhotic liver due to HCV infection. With a median follow-up time of 24.4 months (interquartile range [IQR] 4.7-61.2 months), patient survival was 44.9% and 66.9% for the time periods 1996-2006 and 2007-2015, respectively. Hepatocellular carcinoma (HCC) was present in 30.6% of the patients, and overall postoperative complications had an incidence of 80%. CONCLUSIONS: This is the first report of LT in HCV-infected patients in Colombia and in LA. Our results are comparable to those of other transplant centers worldwide with regard to postoperative complications and patient survival. Patients with LT in the 1996-2006 time frame had higher morbidity and mortality. Studies including larger numbers of patients are needed to determine the reason for this finding.


Assuntos
Hepatite C/cirurgia , Transplante de Fígado , Adulto , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/epidemiologia , Estudos de Coortes , Colômbia , Feminino , Hepacivirus , Hepatite C/complicações , Humanos , Incidência , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/epidemiologia , Transplante de Fígado/mortalidade , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Retrospectivos
9.
Lupus ; 26(11): 1157-1165, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28420067

RESUMO

Background Lupus nephritis (LN) is one of the most frequent complications of SLE and occurs in up to 50% of cases depending on the studied population. Of these, approximately 20% progress to end-stage renal disease (ESRD), with the treatment of choice being a kidney transplant. Objective The objective of this study was to describe the clinical outcome of patients transplanted due to LN, compared with patients transplanted for other causes, in a Latin American population from the Fundación Valle del Lili in Cali, Colombia. Methods Observational, retrospective case study with controls matched by age, sex and type of donor in a single center between 1996 and 2014. Results Sixty-five kidney transplants were performed in patients with LN and ESRD. The survival of patients with LN was 98% at 1, 10 and 15 years ( p = .99). For controls by age and sex, survival was also 98% at 15 years post-transplant, and for controls by donor, the survival rate was 100% at 5 years and 98% at 15 years. Graft survival in patients with LN to 1, 5 and 15 years was 92%, 83% and 71%, respectively; for controls by age and sex, it was 90%, 84% and 64%, respectively, and for the controls by donor, it was 89%, 86% and 79%, respectively ( p = .7718). There were no statistically significant differences found in the cumulative incidence of acute graft rejection in the first year, but it was found that acute rejection is a factor that relates to the loss of function of the renal graft ( p = .032). Of the patients transplanted for LN, two (3.1%) experienced a recurrence of the disease. One patient died after a diagnosis of recurrence of LN due to an infection. Conclusions Kidney transplantation is a good option for patients with ESRD due to LN. In this Hispanic population, the survival of patients, graft survival, and cumulative incidence of graft rejection are not different from those of other transplanted patients. In addition, recurrence of LN was rare, showing the benefits of renal transplantation in LN patients with ESRD.


Assuntos
Falência Renal Crônica/cirurgia , Transplante de Rim , Nefrite Lúpica/cirurgia , Doença Aguda , Adulto , Colômbia , Feminino , Rejeição de Enxerto/epidemiologia , Sobrevivência de Enxerto , Humanos , Incidência , Estimativa de Kaplan-Meier , Falência Renal Crônica/diagnóstico , Falência Renal Crônica/mortalidade , Transplante de Rim/efeitos adversos , Transplante de Rim/mortalidade , Nefrite Lúpica/diagnóstico , Nefrite Lúpica/mortalidade , Masculino , Pessoa de Meia-Idade , Segurança do Paciente , Complicações Pós-Operatórias/epidemiologia , Prevalência , Recidiva , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
10.
Int J Immunogenet ; 44(3): 135-144, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28374494

RESUMO

The minisequencing technique offers accuracy and robustness to genotyping of polymorphic DNA variants, being an excellent option for the identification and analyses of prognostic/susceptibility markers in human diseases. Two multiplex minisequencing assays were designed and standardized to screen 23 candidate SNPs in cytokine, chemokine receptor and ligand genes previously associated with susceptibility to cancer and autoimmune disorders as well as to infectious diseases outcome. The SNPs were displayed in two separate panels (panel 1-IL2 rs2069762, TNFα rs1800629, rs361525; IL4 rs2243250; IL6 rs1800795; IL10 rs1800896, rs1800872; IL17A rs8193036, rs2275913 and panel 2-CCR3 rs309125, CCR4 rs6770096, rs2228428; CCR6 rs968334; CCR8 rs2853699; CXCR3 rs34334103, rs2280964;CXCR6 rs223435, rs2234358; CCL20 rs13034664, rs6749704; CCL22 rs4359426; CXCL10/IP-10 rs3921, rs56061981). A total of 305 DNA samples from healthy individuals were genotyped by minisequencing. To validate the minisequencing technique and to encompass the majority of the potential genotypes for all 23 SNPs, 20 of these samples were genotyped by Sanger sequencing. The results of both techniques were 100% in agreement. The technique of minisequencing showed high accuracy and robustness, avoiding the need for high quantities of DNA template samples. It was easily to be conducted in bulk samples derived from a highly admixed human population, being therefore an excellent option for immunogenetic studies.


Assuntos
Citocinas/genética , Imunogenética/métodos , Receptores de Quimiocinas/genética , Análise de Sequência de DNA/métodos , Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , Doenças Autoimunes/fisiopatologia , Doenças Transmissíveis/genética , Doenças Transmissíveis/imunologia , Doenças Transmissíveis/fisiopatologia , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Humanos , Ligantes , Masculino , Neoplasias/genética , Neoplasias/imunologia , Neoplasias/fisiopatologia , Polimorfismo de Nucleotídeo Único
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