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1.
Heliyon ; 10(15): e34990, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39144990

RESUMO

Rhus aromatica inhabits humid oak and oakpine forests in the State of Michoacán (Mexico). The fruit of R. aromatica is edible and is traditionally used in the preparation of soft drinks, ice pops, ice creams and 'atole'. The objective of the present investigation was to carry out a physical and chemical characterization and analysis of the antioxidant capacity of fruit. For the physical characterization, the equatorial and longitudinal diameter, weight and percentage of pulp were determined. In the chemical characterization, a proximal analysis was carried out, quantification of polyphenols and flavonoids was performed, and the antioxidant capacity was determined. The results showed that the fruit had a longitudinal diameter of 6.58 ± 1.02 mm, an equatorial diameter of 7.17 ± 0.66, a weight of 55.22 ± 5.47 mg, and a 40 % pulp proportion. The chemical characterization analysis indicated 8.7 % moisture, 30.6 % lipids, 8.7 % proteins, 29.4 % total sugars, 3.8 % ashes and 18.7 % crude fibre, 3.1 °Brix, pH 3.1, 1.92 % acidity total and a caloric intake of 4.27 kcal/g. The polyphenol content was higher in 60 % ethanol extracts with 88.6 ± 50.89 mg EAG/g; for flavonoids from extracts with 100 % acetone, it was 26.52 ± 0.65 mg EQ/g, and the total carotenoid content was 46.37 mg/100 g. The total antioxidant activity was higher in extracts with 80 % acetone, with 87.17 % inhibition of the DPPH radical and 90 % inhibition of ABTS without showing a significant difference with the different solvents used. The lowest IC50 values were presented in 100 % ethanol and 60 % methanol extracts for the DPPH radical and for the ABTS radical were the 80 % ethanol and 60 % methanol extracts. The lipid, protein, carotenoid, and polyphenol contents and antioxidant capacity of the fruit of R. aromatica were as high as those of other fruits consumed in the human diet.

2.
Microorganisms ; 9(12)2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34946197

RESUMO

Among people with HIV, histoplasmosis represents an important cause of mortality. Previous studies provided estimates of the disease incidence. Here, we compared those estimates with the results obtained from a screening program implemented in Guatemala, which included histoplasmosis detection for people with HIV. To compare the results of this program with previous estimations, a literature search was performed and reports concerning histoplasmosis incidence were analyzed. The screening program enrolled 6366 patients. The overall histoplasmosis incidence in the screening program was 7.4%, which was almost double that estimated in previous studies. From 2017 to 2019, the screening program showed an upward trend in histoplasmosis cases from 6.5% to 8.8%. Histoplasmosis overall mortality among those who were newly HIV diagnosed showed a decrease at 180 days from 32.8% in 2017 to 21.2% in 2019. The screening approach using rapid diagnostic assays detects histoplasmosis cases more quickly, allowing a specific treatment to be administered, which decreases the mortality of the disease. Therefore, the use of these new techniques, especially in endemic areas of histoplasmosis, must be implemented.

4.
Int J Infect Dis ; 108: 422-427, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34119676

RESUMO

OBJECTIVES: To describe the impact of the coronavirus disease 2019 (COVID-19) pandemic on the diagnosis of human immunodeficiency virus (HIV) and deaths from opportunistic infections in Guatemala. METHODS: A retrospective study was conducted to investigate the impact of the COVID-19 pandemic on people with HIV at a referral clinic (Clinica Familiar Luis Angel García, CFLAG), as well as the disruption of services at a diagnostic laboratory hub (DLH) which provides diagnosis for opportunistic infections to a network of 13 HIV healthcare facilities. Comparative analysis was undertaken using the months March-August from two different time periods: (i) pre-COVID-19 (2017-2019); and (ii) during the COVID-19 period (2020). RESULTS: During the COVID-19 period, 7360 HIV tests were performed at Clinica Familiar Luis Angel García, compared with an average of 16,218 tests in the pre-COVID-19 period; a reduction of 54.7% [95% confidence interval (CI) 53.8-55.4%],Deaths from opportunistic infections at 90 days were 10.7% higher in 2020 compared with 2019 (27.3% vs 16.6%; P = 0.05). Clinical samples sent to the DLH for diagnosis of opportunistic infections decreased by 43.7% in 2020 (95% CI 41.0-46.2%). CONCLUSION: The COVID-19 pandemic is having a substantial impact on HIV care in Guatemala. Diagnostic services for HIV have been severely affected and deaths from opportunistic infections have increased. The lessons learnt must guide the introduction of strategies to reduce the impact of the pandemic.


Assuntos
COVID-19 , Infecções por HIV , Instituições de Assistência Ambulatorial , Guatemala/epidemiologia , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Humanos , Pandemias , Estudos Retrospectivos , SARS-CoV-2
5.
J Fungi (Basel) ; 7(4)2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33916153

RESUMO

Opportunistic infections (OIs) and advanced HIV disease (AHD) contribute to HIV-related mortality. Here, we analyzed the situation of AHD and OIs in a cohort of newly diagnosed HIV patients from Guatemala. We included 2127 adult patients from 13 facilities across the country during 2017 to 2018. Patients were screened for tuberculosis (TB), nontuberculous mycobacteria (NTM), histoplasmosis, and cryptococcal disease, independently of their CD4 cell count. Of the 2127 enrolled patients, 1682 (79.1%) had a CD4 cell count available; of which 52% presented with AHD. Of the Mayan population, 65% had AHD. The overall OI incidence was 21%. Histoplasmosis was the most frequent OI (7.9%), followed by TB (7.1%); 94.4% of these infections occurred in patients with a CD4 < 350 cells/mm3. Mortality at 180 days was significantly higher in those with OIs than without OIs (29.7% vs. 5.9%, p < 0.0001). In one year, this program decreased the OI mortality by 7% and increased the OI treatment by 5.1%. Early OI diagnosis and appropriate therapy reduced OI mortality among newly diagnosed HIV patients in Guatemala. Screening for OIs should be considered in all newly diagnosed HIV patients who have a CD4 cell count < 350 cells/mm3 or those without a CD4 cell count available. To improve results, interventions such as early HIV detection and access to flucytosine and liposomal amphotericin B are required.

6.
ACS Omega ; 6(9): 6112-6123, 2021 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-33718702

RESUMO

Colombia is experiencing significant growth in its agricultural areas, its diverse production chains make the country an excellent candidate in the development of biorefineries, and as a result, there is an increasing need to take full advantage of biomass and obtain high value-added by-products from waste. In this sense, biorefineries are presented as a great alternative for the use of biomass; however, the methodologies of biorefinery synthesis lack a parameter that limits the growth of production lines under incremental exergetic and economic returns. This research develops a biorefinery synthesis methodology using an African palm biorefinery as a case study; a novel approach is developed to facilitate a stop criterion for biorefinery expansion through a combined consideration of economic incremental returns (IROI) and exegetical returns of investment (ExROI), avoiding unnecessary plant expansions or new processes that are not profitable or adequate in terms of useful energy. The development of this methodology required simulations in Aspen Plus software and technical-economic and exergetic evaluation with an incremental approach of four scenarios in Excel. The base case is palm oil production from African palm clusters. The second case includes the production of palm kernel oil and palm cake from residues. The third case implements the production of hydrogen based on other residues from the base case. The last case study incorporates the preceding case and the addition of biodiesel and glycerin production from palm oil. Case 3 exhibits a higher economic performance with an IROI of 42.98%; in terms of exergy, case 2 exhibits considerable improvements over the base case, with an ExROI of 158%. A parameter called the exergo-economic weighted incremental return on investment (IExWROI) was obtained, evidencing a 75% improvement in case 2 compared to the base case. The new indicator aims to provide a more comprehensive approach to biorefinery design by optimization of economic and exergetic returns, contributing a new alternative for decision-making in regard to plant design, plant expansion projects, and implementation of subprocesses.

7.
J Interpers Violence ; 36(23-24): NP12686-NP12707, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-31994433

RESUMO

The aim of this study was to determine whether the experiences of direct or subtle forms of discrimination and violence are associated with mental health in Mexican gay, homosexual, and bisexual (GHB) men. A cross-sectional survey was conducted online; the sample consisted of 4,827 GHB men. Ten forms of overt and subtle sexual orientation-based discrimination and violence (SO-DV) were assessed. Linear and logistic regression models were used to evaluate the association between SO-DV experiences and mental health outcomes. Physical violence was reported less frequently than the other forms of SO-DV. As the number of settings in which SO-DV were experienced increased, a stronger association with negative mental health outcomes was observed. Experiences of subtle SO-DV were associated with increased distress, lower vitality, and increased risk of suicidal ideation. Disapproval of gender nonconformity was associated with negative mental health outcomes independently of violence based on sexual orientation. Subtle forms of SO-DV are more common than direct and overt forms. Both types of SO-DV could negatively affect mental health. Studies investigating these negative experiences are required to gain an understanding of the health inequalities faced by non-heterosexual populations.


Assuntos
Saúde Mental , Minorias Sexuais e de Gênero , Estudos Transversais , Feminino , Humanos , Masculino , México/epidemiologia , Comportamento Sexual , Violência
8.
AIDS ; 34(11): 1625-1632, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32694415

RESUMO

OBJECTIVES: We evaluated the comparative performance of different assays used in a Diagnostic Laboratory Hub that linked 13 HIV healthcare facilities for the diagnosis of tuberculosis (TB), histoplasmosis, and cryptococcosis, and describing its functions in Guatemala compared with other National Reference Laboratories. METHODS: The following diagnostic techniques were analyzed in 24 months (2017-2018) in a cohort of patients with HIV: smear microscopy, mycobacterial and fungal cultures, isolator blood culture, PCR assays, and antigen detection tests. RESULTS: A total of 4245 patients were included, 716 (16.2%) had an opportunistic infection: 249 (34.7%) TB, 40 (5.6%) nontuberculous mycobacteria, 227 (31.7%) histoplasmosis, 138 (19.3%) cryptococcosis, and 62 (8.6%) had multiple opportunistic infections. Two hundred sixty-three [92.6%; 95% confidence interval (CI), 89-95.1] of TB cases were diagnosed by PCR. Urine antigen assay detected 94% (95% CI, 89-96) of the disseminated histoplasmosis cases. A lateral flow assay to detect cryptococcal antigen diagnosed 97% (95% CI, 93.3-98.7%) of the cryptococcal cases. In 85 patients (51.5%) with a cerobrospinal fluid sample, cryptococcal meningitis was diagnosed in 55 (64.7%), of which 18 (32.7%) were only detected by cryptococcal antigen. CONCLUSION: Validated commercial antigen tests, as used in this program, should be the new gold standard for histoplasmosis and cryptococcosis diagnosis. In their absence, 35% of disseminated histoplasmosis and 32.7% of cryptococcal meningitis cases would have been missed. Patients with multiple opportunistic infections were frequently diagnosed and strategies should be designed to screen patients irrespective of their clinical presentation. In low resource settings, Diagnostic Laboratory Hubs can deliver quality diagnostics services in record time at affordable prices.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Criptococose/diagnóstico , Infecções por HIV/complicações , Histoplasmose/diagnóstico , Testes Imunológicos/métodos , Laboratórios/normas , Tuberculose/diagnóstico , Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Adolescente , Adulto , Idoso , Antígenos de Fungos/sangue , Cryptococcus/imunologia , Humanos , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Adulto Jovem
9.
Front Oncol ; 10: 429, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32328457

RESUMO

NH 4 + increased growth rates and final densities of several human metastatic cancer cells. To assess whether glutamate dehydrogenase (GDH) in cancer cells may catalyze the reverse reaction of NH 4 + fixation, its covalent regulation and kinetic parameters were determined under near-physiological conditions. Increased total protein and phosphorylation were attained in NH 4 + -supplemented metastatic cells, but total cell GDH activity was unchanged. Higher V max values for the GDH reverse reaction vs. forward reaction in both isolated hepatoma (HepM) and liver mitochondria [rat liver mitochondria (RLM)] favored an NH 4 + -fixing role. GDH sigmoidal kinetics with NH 4 + , ADP, and leucine fitted to Hill equation showed n H values of 2 to 3. However, the K 0.5 values for NH 4 + were over 20 mM, questioning the physiological relevance of the GDH reverse reaction, because intracellular NH 4 + in tumors is 1 to 5 mM. In contrast, data fitting to the Monod-Wyman-Changeux (MWC) model revealed lower K m values for NH 4 + , of 6 to 12 mM. In silico analysis made with MWC equation, and using physiological concentrations of substrates and modulators, predicted GDH N-fixing activity in cancer cells. Therefore, together with its thermodynamic feasibility, GDH may reach rates for its reverse, NH 4 + -fixing reaction that are compatible with an anabolic role for supporting growth of cancer cells.

10.
Rev. colomb. cienc. pecu ; 31(4): 285-294, oct.-dic. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-985482

RESUMO

Abstract Background: Ehrlichia and Rickettsia are two major rickettsial genera transmitted by ticks that affect a number of wild and domestic animal species and human populations around the world. Objective: To design and validate a duplex PCR for Ehrlichia and Rickettsia in ticks. Methods: Assay validation included testing for sensitivity, specificity, reproducibility, and robustness of the PCR. The groEL and 23sr RNA genes were used for Ehrlichia and Rickettsia, respectively. Results: The limit of detection was one hundred gene copies per 50 μL of reaction for Ehrlichia spp, and one gene copy of Rickettsia per 50 μL of reaction. In general, the primers of the test only amplified in silico those bacterial agents for which they were originally designed, with the exception of the primers for Rickettsia that also amplified Methylocystis sp. The test was reproducible (intermediate precision) 96.7% of the times for both agents. The test was robust enough to tolerate concentration changes of all reagents with the exception of Taq DNA polymerase. Conclusions: The validation results indicated that this PCR is useful for detection in both bacterial genera and it is a good candidate for diagnostic validation.


Resumen Antecedentes: Ehrlichia spp. y Rickettsia spp. son dos de los principales géneros rickettsiales transmitidos por garrapatas que afectan a animales silvestres, domésticos y humanos alrededor del mundo. Objetivo: Diseñar y validar una prueba PCR dúplex para Ehrlichia y Rickettsia en garrapatas. Métodos: La validación de la prueba incluyó ensayos de sensibilidad, especificidad, reproducibilidad y robustez. En la PCR se usó groEL y ARNr 23S como genes blanco para Ehrlichia y Rickettsia, respectivamente. Resultados: El límite de detección fue de 100 copias del gen por 50 μL de reacción para Ehrlichia spp y una copia del gen de Rickettsia por 50 μL de reacción. En general, los cebadores de la prueba solo amplificaron in silico los agentes bacterianos para los cuales fueron originalmente diseñados, con la excepción de los cebadores de Rickettsia que también amplificaron Methylocystis sp. La prueba fue reproducible (precisión intermedia) en un 96.7% de las veces para ambos agentes. La prueba fue suficientemente robusta como para tolerar cambios de concentración de los diferentes reactivos, con excepción de la Taq DNA polimerasa. Conclusión: Los resultados de validación indican que la PCR es útil para detectar ambos géneros bacterianos y podria usarse para validación diagnostica.


Resumo Antecedentes: Ehrlichia e Rickettsia são dois dos principais gêneros de rickettsias transmitidos por carrapatos que infectam tanto animais selvagens quanto animais domésticos e até homens em todo o mundo. Objetivo: O objetivo principal foi elaborar e validar uma PCR duplex para Ehrlichia e Rickettsia em carrapatos. Métodos: A validação incluiu testes de sensibilidade, especificidade, reprodução e robustez. Para o PCR, utilizamos os genes groEl e 23Sr-RNA para Ehrlichia e Rickettsia, respectivamente. Resultados: O limite de detecção foi de 100 cópias de genes por 50 ml de reação para Erliquia spp e uma cópia de gene de Rickettsia por 50 ml de reação. Em geral, os iniciadores dos testes amplificaram em modelos computacionais os agentes bacterianos para os quais eles foram projetados, exceto os primers de Rickettsia que também amplificou Methylocystis sp. Os testes foram reproduzíveis (precisão intermediária) 96,7% para ambos os agentes e foram também robustos para tolerar mudanças de concentração em todos os reagentes, exceto o reagente Taq DNA polymerase. Conclusões: Os resultados da validação indicaram que o PCR é útil para detecção em ambos os gêneros bacterianos, portanto, um bom exame para validação diagnóstica.

11.
Front Plant Sci ; 7: 1649, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28018365

RESUMO

Breeding cassava relies on a phenotypic recurrent selection that takes advantage of the vegetative propagation of this crop. Successive stages of selection (single row trial-SRT; preliminary yield trial-PYT; advanced yield trial-AYT; and uniform yield trials UYT), gradually reduce the number of genotypes as the plot size, number of replications and locations increase. An important feature of this scheme is that, because of the clonal, reproduction of cassava, the same identical genotypes are evaluated throughout these four successive stages of selection. For this study data, from 14 years (more than 30,000 data points) of evaluation in a sub-humid tropical environment was consolidated for a meta-analysis. Correlation coefficients for fresh root yield (FRY), dry matter content (DMC), harvest index (HIN), and plant type score (PTS) along the different stages of selection were estimated. DMC and PTS measured in different trials showed the highest correlation coefficients, indicating a relatively good repeatability. HIN had an intermediate repeatability, whereas FRY had the lowest value. The association between HIN and FRY was lower than expected, suggesting that HIN in early stages was not reliable as indirect selection for FRY in later stages. There was a consistent decrease in the average performance of clones grown in PYTs compared with the earlier evaluation of the same genotypes at SRTs. A feasible explanation for this trend is the impact of the environment on the physiological and nutritional status of the planting material and/or epigenetic effects. The usefulness of HIN is questioned. Measuring this variable takes considerable efforts at harvest time. DMC and FRY showed a weak positive association in SRT (r = 0.21) but a clearly negative one at UYT (r = -0.42). The change in the relationship between these variables is the result of selection. In later stages of selection, the plant is forced to maximize productivity on a dry weight basis either by maximizing FRY or DMC, but not both. Alternatively, the plant may achieve high dry root yield by simultaneously attaining "acceptable" (but not maximum) levels of FRY and DMC.

12.
Front Plant Sci ; 7: 1227, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27621734

RESUMO

Breeding cassava relies on several selection stages (single row trial-SRT; preliminary; advanced; and uniform yield trials-UYT). This study uses data from 14 years of evaluations. From more than 20,000 genotypes initially evaluated only 114 reached the last stage. The objective was to assess how the data at SRT could be used to predict the probabilities of genotypes reaching the UYT. Phenotypic data from each genotype at SRT was integrated into the selection index (SIN) used by the cassava breeding program. Average SIN from all the progenies derived from each progenitor was then obtained. Average SIN is an approximation of the breeding value of each progenitor. Data clearly suggested that some genotypes were better progenitors than others (e.g., high number of their progenies reaching the UYT), suggesting important variation in breeding values of progenitors. However, regression of average SIN of each parental genotype on the number of their respective progenies reaching UYT resulted in a negligible coefficient of determination (r (2) = 0.05). Breeding value (e.g., average SIN) at SRT was not efficient predicting which genotypes were more likely to reach the UYT stage. Number of families and progenies derived from a given progenitor were more efficient predicting the probabilities of the progeny from a given parent reaching the UYT stage. Large within-family genetic variation tends to mask the true breeding value of each progenitor. The use of partially inbred progenitors (e.g., S1 or S2 genotypes) would reduce the within-family genetic variation thus making the assessment of breeding value more accurate. Moreover, partial inbreeding of progenitors can improve the breeding value of the original (S0) parental material and sharply accelerate genetic gains. For instance, homozygous S1 genotypes for the dominant resistance to cassava mosaic disease (CMD) could be generated and selected. All gametes from these selected S1 genotypes would carry the desirable allele and 100% of their progenies would be resistant. Only half the gametes produced by the heterozygous S0 progenitor would carry the allele of interest. For other characteristics, progenies from the S1 genotypes should be, at worst, similar to those generated by the S0 progenitors.

13.
Medwave ; 16(4): e6453, 2016 May 26.
Artigo em Espanhol, Inglês | MEDLINE | ID: mdl-27281468

RESUMO

Squamous cell carcinoma of the conjunctiva is the most frequent malignant tumor of the ocular surface. It is a rare disease with an incidence of 0.13 to 1.9 per 100,000 inhabitants, mainly affecting individuals between 50 and 75 years of age. It tends to have a slow, non-aggressive course. Treatment depends on the extent of the tumor. If there is intraocular involvement, enucleation is indicated, and in the presence of extraocular involvement the orbital exenteration is the standard treatment. We report and discuss the case of an 82 year old male patient having a conjunctival squamous cell carcinoma with intra and extraocular involvement, together with a review of the literature.


El carcinoma escamoso de la conjuntiva es el tumor maligno más frecuente de la superficie ocular. Constituye una enfermedad rara con una incidencia de 0,13 a 1,9 por 100 000 habitantes que afecta principalmente a individuos entre los 50 y los 75 años. Suele tener un curso lento y poco agresivo. El tratamiento depende de la extensión tumoral. En presencia de compromiso intraocular la enucleación está indicada y en presencia de compromiso extraocular la exanteración orbitaria es el tratamiento estándar. Reportamos el caso de un paciente de 82 años con carcinoma escamoso conjuntival con compromiso intra y extraocular, se discute el caso y se revisa la literatura.

14.
Spinal Cord Ser Cases ; 2: 16007, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28053751

RESUMO

Spontaneous spinal epidural hematoma (SSEH) is a rare cause of spinal cord compression. Symptoms may include sudden-onset axial pain followed by neurologic involvement including weakness, numbness and incontinence. Here we report the case of a patient followed prospectively after surgical intervention following SSEH and recovery following inpatient rehabilitation. This patient presented with right hemiplegia, neurogenic bladder and bowel with autonomic dysfunction. the patient with significant gains in Functional Independence Measure scale that improved from 15 on admission to 35 1 month following surgery. This case suggests that treating this type of patients requires hospitals specialized in spinal cord injury.

15.
Plant Physiol Biochem ; 86: 166-173, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25500453

RESUMO

A recent proposal to mitigate the effects of climatic change and reduce water consumption in agriculture is to develop cultivars with high water-use efficiency. The aims of this study were to characterize this trait as a differential response mechanism to water-limitation in two bean cultivars contrasting in their water stress tolerance, to isolate and identify gene fragments related to this response in a model cultivar, as well as to evaluate transcription levels of genes previously identified. Keeping CO2 assimilation through a high photosynthesis rate under limited conditions was the physiological response which allowed the cultivar model to maintain its growth and seed production with less water. Chloroplast genes stood out among identified genetic elements, which confirmed the importance of photosynthesis in such response. ndhK, rpoC2, rps19, rrn16, ycf1 and ycf2 genes were expressed only in response to limited water availability.


Assuntos
Fabaceae/genética , Genes de Cloroplastos/genética , Genes de Plantas/genética , Fotossíntese/genética , Água/metabolismo , Adaptação Fisiológica/genética , Biomassa , Secas , Fabaceae/classificação , Fabaceae/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Especificidade da Espécie
16.
Ann Hepatol ; 14(1): 64-74, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25536643

RESUMO

BACKGROUND AND AIM: Hepatocellular carcinoma (HCC) is the most common primary liver cancer diagnosed worldwide. Deregulation of Wnt/beta-catenin pathway has been associated with the development of HCC in a substantial number of cases in Europe and far less in Asia. Nothing is known about this pathway in HCC cases from South America. This study aimed to investigate the frequency of mutations in beta-catenin gene (CTNNB1) and the subcellular localization of beta-catenin in HCC cases from Colombia. MATERIAL AND METHODS: We determine by direct sequencing the frequency of mutations in exon 3 of CTNNB1 gene and by immunohistochemistry the subcellular localization of beta-catenin in 54 samples of HCC obtained from three pathology units in Bogota and Medellin cities. RESULTS: Only three HCC cases (5.6%) were found mutated at residues (G34E, S45P, P44S, T41I) important for phosphorylation and ubiquitination of beta-catenin protein. Strikingly, nuclear or cytoplasmic accumulation of beta-catenin, hallmark of Wnt pathway activation, was found in 42.6% HCC cases (23/54). Interestingly, beta-catenin accumulation was significantly more frequent in young patients and hepatitis B virus-related HCC. CONCLUSIONS: Although, CTNNB1 exon 3 mutations are not frequent in HCC from Colombian patients, our findings indicate that Wnt/beta-catenin signaling is activated in 42.6% of HCC samples. Furthermore, Wnt signaling was demonstrated in HCC cases associated of HBV infection, one of the most important HCC risk factors in Colombia.


Assuntos
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Mutação , Via de Sinalização Wnt/genética , beta Catenina/genética , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/patologia , Estudos de Coortes , Colômbia , Éxons , Feminino , Hepatite B Crônica/complicações , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estudos Retrospectivos , beta Catenina/metabolismo
17.
BMC Public Health ; 14: 674, 2014 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-24990155

RESUMO

BACKGROUND: Vector-borne diseases (VBDs) and mosquito control programs (MCPs) diverge in settings and countries, and lead control specialists need to be aware of the most effective control strategies. Integrated Vector Management (IVM) strategies, once implemented in MCPs, aim to reduce cost and optimize protection of the populations against VBDs. This study presents a strengths, weaknesses, opportunities, and threats (SWOT) analysis to compare IVM strategies used by MCPs in Saint Johns County, Florida and Guayas, Ecuador. This research evaluates MCPs strategies to improve vector control activities. METHODS: Methods included descriptive findings of the MCP operations. Information was obtained from vector control specialists, directors, and residents through field trips, surveys, and questionnaires. Evaluations of the strategies and assets of the control programs where obtained through SWOT analysis and within an IVM approach. RESULTS: Organizationally, the Floridian MCP is a tax-based District able to make decisions independently from county government officials, with the oversight of an elected board of commissioners. The Guayas program is directed by the country government and assessed by non-governmental organizations like the World health Organization. Operationally, the Floridian MCP conducts entomological surveillance and the Ecuadorian MCP focuses on epidemiological monitoring of human disease cases. Strengths of both MCPs were their community participation and educational programs. Weaknesses for both MCPs included limitations in budgets and technical capabilities. Opportunities, for both MCPs, are additional funding and partnerships with private, non-governmental, and governmental organizations. Threats experienced by both MCPs included political constraints and changes in the social and ecological environment that affect mosquito densities and control efforts. IVM pillars for policy making were used to compare the information among the programs. Differences included how the Ecuadorian MCP relies heavily on the community for vector control while the American MCP relies on technologies and research. CONCLUSION: IVM based recommendations direct health policy leaders toward improving surveillance systems both entomologically and epidemiologically, improving community risk perceptions by integrating components of community participation, maximizing resources though the use of applied research, and protecting the environment by selecting low-risk pesticides. Outcomes of the research revealed that inter-sectorial and multidisciplinary interventions are critical to improve public health.


Assuntos
Participação da Comunidade , Eficiência Organizacional , Controle de Mosquitos/métodos , Integração de Sistemas , Animais , Técnicas de Apoio para a Decisão , Vetores de Doenças , Equador , Florida , Política de Saúde , Humanos , Controle de Mosquitos/organização & administração , Formulação de Políticas , Saúde Pública , Organização Mundial da Saúde
18.
FEBS J ; 281(15): 3325-45, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24912776

RESUMO

UNLABELLED: The effect of hypoglycemia on the contents of glycolytic proteins, activities of enzymes/transporters and flux of HeLa and MCF-7 tumor cells was experimentally analyzed and modeled in silico. After 24 h hypoglycemia (2.5 mm initial glucose), significant increases in the protein levels of glucose transporters 1 and 3 (GLUT 1 and 3) (3.4 and 2.1-fold, respectively) and hexokinase I (HKI) (2.3-fold) were observed compared to the hyperglycemic standard cell culture condition (25 mm initial glucose). However, these changes did not bring about a significant increase in the total activities (Vmax ) of GLUT and HK; instead, the affinity of these proteins for glucose increased, which may explain the twofold increased glycolytic flux under hypoglycemia. Thus, an increase in more catalytically efficient isoforms for two of the main controlling steps was sufficient to induce increased flux. Further, a previous kinetic model of tumor glycolysis was updated by including the ratios of GLUT and HK isoforms, modified pyruvate kinase kinetics and an oxidative phosphorylation reaction. The updated model was robust in terms of simulating most of the metabolite levels and fluxes of the cells exposed to various glycemic conditions. Model simulations indicated that the main controlling steps were glycogen degradation > HK > hexosephosphate isomerase under hyper- and normoglycemia, and GLUT > HK > glycogen degradation under hypoglycemia. These predictions were experimentally evaluated: the glycolytic flux of hypoglycemic cells was more sensitive to cytochalasin B (a GLUT inhibitor) than that of hyperglycemic cells. The results indicated that cancer glycolysis should be inhibited at multiple controlling sites, regardless of external glucose levels, to effectively block the pathway. DATABASE: The mathematical models described here have been submitted to the JWS Online Cellular Systems Modelling Database and can be accessed at http://jjj.mib.ac.uk/database/achcar/index.html. [Database section added 21 July 2014 after original online publication].


Assuntos
Glicólise , Hipoglicemia/metabolismo , Neoplasias/metabolismo , Proliferação de Células , Glucose/fisiologia , Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Células HeLa , Hexoquinase/química , Hexoquinase/metabolismo , Humanos , Isoenzimas/química , Isoenzimas/metabolismo , Cinética , L-Lactato Desidrogenase/metabolismo , Células MCF-7 , Modelos Biológicos , Transportadores de Ácidos Monocarboxílicos/metabolismo , Fosfofrutoquinase-1/metabolismo , Piruvato Quinase/metabolismo , Simportadores/metabolismo
19.
Rev. salud pública ; Rev. salud pública;11(5): 700-712, oct. 2009. tab
Artigo em Espanhol | LILACS | ID: lil-541801

RESUMO

Objetivo Analizar los factores asociados con el uso inconsistente de condón en hombres que tienen sexo con hombres (HSH) de Ciudad Juárez, Chihuahua. Material y métodos Se realizó un estudio observacional, transversal y analítico con una muestra por conveniencia (n=186) de HSH de Ciudad Juárez. Las variables independientes fueron: nivel socioeconómico, actitudes hacia del uso del condón, uso de drogas, consumo de alcohol, identidad por orientación sexual y la discriminación por orientación sexual. Las prácticas sexuales que se relacionan con la infección por VIH (uso inconsistente de condón y recibir semen en boca o ano) fueron consideradas como variables dependientes. Resultados. El 30,0 por ciento de los HSH entrevistado usaba condón de manera inconsistente cuando practicaban sexo anal receptivo, mientras que la proporción fue de 39,1 por ciento cuando tenían sexo anal insertivo; y el 35,5 por ciento reportaron que recibían semen en la boca o ano. Mediante modelos de regresión logística multivariada se observó que los siguientes grupos tuvieron mayor probabilidad de mantener alguna práctica sexual de riesgo: los sujetos de menor edad, con ingreso medio, que presentan actitudes negativas hacia el uso del condón, que consumen drogas o alcohol y que asumían una identidad homosexual. Conclusiones. Una proporción importante de los HSH entrevistados de la Ciudad Juárez tiene uso inconsistente de condón. Se discuten las implicaciones que tienen los hallazgos en el diseño de programas encaminados a promover el uso de condón entre los HSH.


Objective Analysing the factors associated with inconsistent condom use amongst men having sex with other men (MSM) in Ciudad Juárez, Chihuahua. Materials and methods This was an observational, cross-sectional analytic study using a convenience sample (n=186) of MSM from Ciudad Juarez. Socioeconomic status, attitudes toward condom use, drug use, alcohol consumption, sexual orientation were considered as independent variables. Dependent variables were sexual behaviour related to HIV infection (inconsistent condom use in anal penetration and receiving semen in the mouth or anus). Results Whereas 30 percent of the MSM interviewed infrequently used a condom when they practiced receptive anal sex, when they had insertive anal sex, 39.1 percent reported receiving semen in the mouth and 35.5 percent in the anus. Multivariate logistic regression models were used, observing that the groups of men having the highest probability of risky sexual behavior (compared to their counterparts) were younger men (<20 years), those earning medium income, those having a negative attitude towards condom use, men using drugs or alcohol and those who reported homosexual identity. Conclusions An important percentage of MSM infrequently used a condom. The implications of our findings should be used when designing programmes for promoting condom use amongst MSM.


Assuntos
Adulto , Humanos , Masculino , Adulto Jovem , Preservativos , Homossexualidade Masculina , Estudos Transversais , México , Saúde da População Urbana , Adulto Jovem
20.
Mini Rev Med Chem ; 9(9): 1084-101, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19689405

RESUMO

To develop new and more efficient anti-cancer strategies it will be important to characterize the products of transcription factor activity essential for tumorigenesis. One such factor is hypoxia-inducible factor-1alpha (HIF-1alpha), a transcription factor induced by low oxygen conditions and found in high levels in malignant solid tumors, but not in normal tissues or slow-growing tumors. In fast-growing tumors, HIF-1alpha is involved in the activation of numerous cellular processes including resistance against apoptosis, over-expression of drug efflux membrane pumps, vascular remodeling and angiogenesis as well as metastasis. In cancer cells, HIF-1alpha induces over-expression and increased activity of several glycolytic protein isoforms that differ from those found in non-malignant cells, including transporters (GLUT1, GLUT3) and enzymes (HKI, HKII, PFK-L, ALD-A, ALD-C, PGK1, ENO-alpha, PYK-M2, LDH-A, PFKFB-3). The enhanced tumor glycolytic flux triggered by HIF-1alpha also involves changes in the kinetic patterns of expressed isoforms of key glycolytic enzymes. The HIF-1alpha induced isoforms provide cancer cells with reduced sensitivity to physiological inhibitors, lower affinity for products and higher catalytic capacity (Vmax(f)) in forward reactions because of marked over-expression compared to those isoforms expressed in normal tissues. Some of the HIF1alpha-induced glycolytic isoforms also participate in survival pathways, including transcriptional activation of H2B histone (by LDH-A), inhibition of apoptosis (by HKII) and promotion of cell migration (by ENO-alpha). HIF-1alpha action may also modulate mitochondrial function and oxygen consumption by inactivating the pyruvate dehydrogenase complex in some tumor types, or by modulating cytochrome c oxidase subunit 4 expression to increase oxidative phosphorylation in other cancer cell lines. In this review, the roles of HIF-1alpha and HIF1alpha-induced glycolytic enzymes are examined and it is concluded that targeting the HIF1alpha-induced glucose transporter and hexokinase, important to glycolytic flux control, might provide better therapeutic targets for inhibiting tumor growth and progression than targeting HIF1alpha itself.


Assuntos
Regulação Neoplásica da Expressão Gênica , Glicólise , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Animais , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo
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