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1.
Malar J ; 23(1): 130, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38693572

RESUMEN

BACKGROUND: The sequestration of Plasmodium falciparum infected erythrocytes in the placenta, and the resulting inflammatory response affects maternal and child health. Despite existing information, little is known about the direct impact of P. falciparum on the placental barrier formed by trophoblast and villous stroma. This study aimed to assess placental tissue damage caused by P. falciparum in human placental explants (HPEs). METHODS: HPEs from chorionic villi obtained of human term placentas (n = 9) from normal pregnancies were exposed to P. falciparum-infected erythrocytes (IE) for 24 h. HPEs were embedded in paraffin blocks and used to study tissue damage through histopathological and histochemical analysis and apoptosis using TUNEL staining. Culture supernatants were collected to measure cytokine and angiogenic factors and to determine LDH activity as a marker of cytotoxicity. A subset of archived human term placenta paraffin-embedded blocks from pregnant women with malaria were used to confirm ex vivo findings. RESULTS: Plasmodium falciparum-IE significantly damages the trophoblast layer and the villous stroma of the chorionic villi. The increased LDH activity and pathological findings such as syncytial knots, fibrin deposits, infarction, trophoblast detachment, and collagen disorganization supported these findings. The specific damage to the trophoblast and the thickening of the subjacent basal lamina were more pronounced in the ex vivo infection. In contrast, apoptosis was higher in the in vivo infection. This disparity could be attributed to the duration of exposure to the infection, which significantly varied between individuals naturally exposed over time and the 24-h exposure in the ex vivo HPE model. CONCLUSION: Exposure to P. falciparum-IE induces a detachment of the syncytiotrophoblast, disorganization of the stroma villi, and an increase in apoptosis, alterations that may be associated with adverse results such as intrauterine growth restriction and low birth weight.


Asunto(s)
Vellosidades Coriónicas , Plasmodium falciparum , Trofoblastos , Humanos , Femenino , Vellosidades Coriónicas/parasitología , Vellosidades Coriónicas/patología , Embarazo , Plasmodium falciparum/fisiología , Trofoblastos/parasitología , Apoptosis , Malaria Falciparum/parasitología , Malaria Falciparum/patología , Placenta/parasitología , Placenta/patología , Citocinas/metabolismo
2.
Medicina (Kaunas) ; 60(3)2024 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-38541155

RESUMEN

Background and Objectives: Non-alcoholic fatty liver disease (NAFLD) is highly prevalent worldwide. It progresses from simple steatosis to non-alcoholic steatohepatitis (NASH). Fibrosis is often present during NAFLD progression; however, factors determining which subjects develop NASH or fibrosis are unclear. Insulin-like growth factor binding proteins (IGFBPs) are a family of secreted proteins involved in senescence and scarring, mainly synthetized in the liver. Here, we aimed to study the association of IGFBPs and their induced senescence with the progression of NAFLD and liver fibrosis. Materials and Methods: A total of 16-week-old male C57BL/6 mice weighing 23 ± 3 g were fed either methionine/choline-deficient (MCD) or control diet for 2, 8, or 12 weeks. Blood and liver samples were collected, and a histological assessment of NAFLD and fibrosis was performed. Fat contents were measured. Cellular senescence was evaluated in the liver. IGFBP levels were assessed in the liver and serum. Data were expressed as mean ± SD and analyzed by a one-way ANOVA followed by Tukey's test. Lineal regression models were applied for NAFLD and fibrosis progression. p < 0.05 was considered significant. Results: IGFBP-1 and -2 were increased in serum during NAFLD. IGFBP-7 was significantly increased in the serum in NASH compared with the controls. Senescence increased in NAFLD. Serum and liver IGFBP-7 as well as SA-ß-gal activity increased as fibrosis progressed. Both IGFBP-7 and cellular senescence were significantly higher during NAFLD and fibrosis in MCD-fed mice. Conclusions: IGFBP-1, -2, and -7, through their consequent senescence, have a role in the progression of NAFLD and its associated fibrosis, being a plausible determinant in the progression from steatosis to NASH.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Masculino , Humanos , Ratones , Animales , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Proteína 1 de Unión a Factor de Crecimiento Similar a la Insulina , Péptidos Similares a la Insulina , Ratones Endogámicos C57BL , Hígado , Cirrosis Hepática/complicaciones , Colina/metabolismo , Colina/farmacología , Senescencia Celular , Modelos Animales de Enfermedad
3.
Arch Virol ; 168(8): 218, 2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37530901

RESUMEN

The human immunodeficiency virus type 1 (HIV-1) reservoir, composed of cells harboring the latent, integrated virus, is not eliminated by antiretroviral therapy. It therefore represents a significant barrier to curing the infection. The biology of HIV-1 reservoirs, the mechanisms of their persistence, and effective strategies for their eradication are not entirely understood. Here, we review the molecular mechanisms by which HIV-1 reservoirs develop, the cells and compartments where the latent virus resides, and advancements in curative therapeutic strategies. We first introduce statistics and relevant data on HIV-1 infection, aspects of pathogenesis, the role of antiretroviral therapy, and the general features of the latent HIV reservoir. Then, the article is built on three main pillars: The molecular mechanisms related to latency, the different strategies for targeting the reservoir to obtain a cure, and the current progress in immunotherapy to counteract said reservoirs.


Asunto(s)
Infecciones por VIH , VIH-1 , Humanos , VIH-1/genética , Infecciones por VIH/tratamiento farmacológico , Latencia del Virus , Linfocitos T CD4-Positivos , Replicación Viral
4.
Epilepsy Behav ; 131(Pt A): 108668, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35483205

RESUMEN

BACKGROUND: Neurocysticercosis (NCC) is a common cause of late-onset epilepsy worldwide, but there is still minimal information regarding its impact on a patient's quality of life. This study evaluated quality of life in a series of patients with epilepsy secondary to NCC using the QOLIE (Quality of Life in Epilepsy)-31 questionnaire. METHODOLOGY: This cross-sectional study included 155 Peruvian patients between 16 and 70 years of age with epilepsy due to viable intraparenchymal NCC, who enrolled in two trials of anti-parasitic treatment during the period 2006-2011. The QOLIE-31 questionnaire was applied before the onset of anti-parasitic treatment. The associations between QOLIE-31 scores, sociodemographic characteristics, clinical, and neuroimaging data were analyzed with Kruskal-Wallis test and generalized linear models (GLM). RESULTS: The average QOLIE-31 score was 55.8 (SD ±â€¯7.6), with 119 individuals (76.8%) scoring in the poor quality-of-life category. Generalized tonic-clonic seizures and secondarily generalized epileptic seizures were associated with a lower QOLIE-31, as well as a low level of education with a value of p = 0.05. There were no associations between QOLIE-31 scores and other variables such as sex, age, antiepileptic medication, number of parasitic cysts, and number of compromised brain regions. On multivariate analysis, a greater number of generalized epileptic seizures maintained a statistically significant association with detrimental QOLIE-31 scores. CONCLUSION: Quality of life is affected in NCC, mainly in relation to the number of prior generalized epileptic seizures.


Asunto(s)
Epilepsia , Neurocisticercosis , Estudios Transversales , Epilepsia/tratamiento farmacológico , Epilepsia/etiología , Humanos , Neurocisticercosis/complicaciones , Neurocisticercosis/diagnóstico por imagen , Calidad de Vida , Convulsiones/diagnóstico por imagen , Convulsiones/tratamiento farmacológico , Convulsiones/etiología , Encuestas y Cuestionarios
5.
Traffic ; 19(11): 879-892, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30095213

RESUMEN

Deficiency in diacylglycerol acyltransferase (DGAT1) is a rare cause of neonatal diarrhea, without a known mechanism or in vitro model. A patient presenting at our institution at 7 weeks of life with failure to thrive and diarrhea was found by whole-exome sequencing to have a homozygous DGAT1 truncation mutation. Duodenal biopsies showed loss of DGAT1 and deficits in apical membrane transporters and junctional proteins in enterocytes. When placed on a very low-fat diet, the patient's diarrhea resolved with normalization of brush border transporter localization in endoscopic biopsies. DGAT1 knockdown in Caco2-BBe cells modeled the deficits in apical trafficking, with loss of apical DPPIV and junctional occludin. Elevation in cellular lipid levels, including diacylglycerol (DAG) and phospholipid metabolites of DAG, was documented by lipid analysis in DGAT1 knockdown cells. Culture of the DGAT1 knockdown cells in lipid-depleted media led to re-establishment of occludin and return of apical DPPIV. DGAT1 loss appears to elicit global changes in enterocyte polarized trafficking that could account for deficits in absorption seen in the patient. The in vitro modeling of this disease should allow for investigation of possible therapeutic targets.


Asunto(s)
Diacilglicerol O-Acetiltransferasa/genética , Diarrea Infantil/genética , Enfermedades del Sistema Digestivo/genética , Células CACO-2 , Preescolar , Diacilglicerol O-Acetiltransferasa/deficiencia , Diacilglicerol O-Acetiltransferasa/metabolismo , Diarrea Infantil/patología , Enfermedades del Sistema Digestivo/patología , Humanos , Lactante , Absorción Intestinal , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Masculino , Transporte de Proteínas
6.
Ann Hepatol ; 18(4): 553-562, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31126882

RESUMEN

Liver disease during pregnancy is more common than expected and may require specialized intervention. It is important to determine if changes in liver physiology may develop into liver disease, to assure early diagnosis. For adequate surveillance of mother-fetus health outcome, liver disease during pregnancy might require intervention from a hepatologist. Liver diseases have a prevalence of at least 3% of all pregnancies in developed countries, and they are classified into two main categories: related to pregnancy; and those non- related that are present de novo or are preexisting chronic liver diseases. In this review we describe and discuss the main characteristics of those liver diseases associated with pregnancy and only some frequent pre-existing and co-incidental in pregnancy are considered. In addition to the literature review, we compiled the data of liver disease occurring during pregnancies attended at the National Institute of Perinatology in Mexico City in a three-year period. In our tertiary referral women hospital, liver disease was present in 11.24 % of all pregnancies. Associated liver disease was found in 10.8% of all pregnancies, mainly those related to pre-eclampsia (9.9% of pregnancies). Only 0.56% was due to liver disease that was co-incidental or preexisting; the acute or chronic hepatitis C virus was the most frequent in this group (0.12%). When managing pregnancy in referral hospitals in Latin America, it is important to discard liver alterations early for adequate follow up of the disease and to prevent adverse consequences for the mother and child.


Asunto(s)
Hepatopatías/terapia , Complicaciones del Embarazo/terapia , Síndrome de Budd-Chiari/epidemiología , Síndrome de Budd-Chiari/fisiopatología , Síndrome de Budd-Chiari/terapia , Colestasis Intrahepática/epidemiología , Colestasis Intrahepática/fisiopatología , Colestasis Intrahepática/terapia , Hígado Graso/epidemiología , Hígado Graso/fisiopatología , Hígado Graso/terapia , Femenino , Síndrome HELLP/epidemiología , Síndrome HELLP/fisiopatología , Síndrome HELLP/terapia , Hepatitis Viral Humana/epidemiología , Hepatitis Viral Humana/fisiopatología , Hepatitis Viral Humana/terapia , Degeneración Hepatolenticular/epidemiología , Degeneración Hepatolenticular/fisiopatología , Degeneración Hepatolenticular/terapia , Humanos , Hiperemesis Gravídica/epidemiología , Hiperemesis Gravídica/fisiopatología , Hiperemesis Gravídica/terapia , Hipertensión Portal/epidemiología , Hipertensión Portal/fisiopatología , Hipertensión Portal/terapia , Recién Nacido , Cirrosis Hepática/epidemiología , Cirrosis Hepática/fisiopatología , Cirrosis Hepática/terapia , Hepatopatías/epidemiología , Hepatopatías/fisiopatología , Trasplante de Hígado , México/epidemiología , Preeclampsia/epidemiología , Preeclampsia/fisiopatología , Preeclampsia/terapia , Embarazo , Complicaciones del Embarazo/epidemiología , Complicaciones del Embarazo/fisiopatología , Complicaciones Infecciosas del Embarazo/epidemiología , Complicaciones Infecciosas del Embarazo/fisiopatología , Complicaciones Infecciosas del Embarazo/terapia , Centros de Atención Terciaria
7.
Molecules ; 24(17)2019 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-31470620

RESUMEN

Non-alcoholic fatty liver disease is a highly prevalent condition worldwide that increases the risk to develop liver fibrosis, cirrhosis, and hepatocellular carcinoma. Thus, it is imperative to develop novel diagnostic tools that together with liver biopsy help to differentiate mild and advanced degrees of steatosis. Ex-vivo liver samples were collected from mice fed a methionine-choline deficient diet for two or eight weeks, and from a control group. The degree of hepatic steatosis was histologically evaluated, and fat content was assessed by Oil-Red O staining. On the other hand, fluorescence spectroscopy was used for the assessment of the steatosis progression. Fluorescence spectra were recorded at excitation wavelengths of 330, 365, 385, 405, and 415 nm by establishing surface contact of the fiber optic probe with the liver specimens. A multi-variate statistical approach based on principal component analysis followed by quadratic discriminant analysis was applied to spectral data to obtain classifiers able to distinguish mild and moderate stages of steatosis at the different excitation wavelengths. Receiver Operating Characteristic (ROC) curves were computed to compare classifier's performances for each one of the five excitation wavelengths and steatosis stages. Optimal sensitivity and specificity were calculated from the corresponding ROC curves using the Youden index. Intensity in the endogenous fluorescence spectra at the given wavelengths progressively increased according to the time of exposure to diet. The area under the curve of the spectra was able to discriminate control liver samples from those with steatosis and differentiate among the time of exposure to the diet for most of the used excitation wavelengths. High specificities and sensitivities were obtained for every case; however, fluorescence spectra obtained by exciting with 405 nm yielded the best results distinguishing between the mentioned classes with a total classification error of 1.5% and optimal sensitivities and specificities better than 98.6% and 99.3%, respectively.


Asunto(s)
Tejido Adiposo/diagnóstico por imagen , Deficiencia de Colina/diagnóstico por imagen , Hígado/diagnóstico por imagen , Metionina/deficiencia , Enfermedad del Hígado Graso no Alcohólico/diagnóstico por imagen , Espectrometría de Fluorescencia/métodos , Tejido Adiposo/química , Tejido Adiposo/patología , Animales , Área Bajo la Curva , Deficiencia de Colina/metabolismo , Deficiencia de Colina/patología , Análisis Discriminante , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Humanos , Hígado/química , Hígado/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Análisis de Componente Principal , Curva ROC , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad , Espectrometría de Fluorescencia/normas
8.
Reprod Biomed Online ; 37(6): 732-740, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30539738

RESUMEN

RESEARCH QUESTION: What is the association between prenatal exposure to persistent organic pollutants, separately and combined, and anogenital distance (in-utero endocrine disruption marker). DESIGN: A cohort study conducted in Sonora, Mexico. Blood concentrations of polychlorobiphenyls (PCB) 28, 74, 118, 138/158, 153, 170, 180 and the isomers of dichlorodiphenyltrichloroethane (DDT) and its metabolites were determined in women in the third trimester of pregnancy; three variants of anogenital distance were measured on five occasions during the first year of life of their infants: 82 girls (402 observations) and 74 boys (356 observations). RESULTS: Boys had negative and significant associations between anogenital distance/height and the concentrations of PCB 28 (beta = - 0.005;P = 0.006), PCB 74 (beta = - 0.003;P = 0.013), and PCB 170 (beta = - 0.005;P = 0.001) when analysed individually. Negative and significant associations were also found using statistical models applied to mixtures of compounds. The latter associations were sometimes larger in magnitude and significance, suggesting a possible potentiation of the compounds. No associations were observed between anogenital distance and DDT in either sex or with PCB in girls. CONCLUSIONS: The decreased anogenital distance associated with prenatal exposure to the persistent organic pollutants, observed consistently in different analyses, suggests an under-masculinizing effect of these environmental pollutants in boys.


Asunto(s)
DDT/toxicidad , Contaminantes Ambientales/toxicidad , Desarrollo Fetal/efectos de los fármacos , Bifenilos Policlorados/toxicidad , Efectos Tardíos de la Exposición Prenatal , Canal Anal/anatomía & histología , Canal Anal/efectos de los fármacos , Canal Anal/embriología , Antropometría , Estudios de Cohortes , DDT/sangre , Contaminantes Ambientales/sangre , Femenino , Genitales/anatomía & histología , Genitales/efectos de los fármacos , Genitales/embriología , Humanos , Masculino , México , Bifenilos Policlorados/sangre , Embarazo , Tercer Trimestre del Embarazo
9.
J Surg Oncol ; 115(3): 273-280, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27861915

RESUMEN

Arginine is an important player in numerous biologic processes and studies have demonstrated its importance for cellular growth that becomes limiting in states of rapid turnover (e.g., malignancy). Thus, arginine deprivation therapy is being examined as an adjuvant cancer therapy, however, arginine is also necessary for immune destruction of malignant cells. Herein we review the data supporting arginine deprivation or supplementation in cancer treatment and the currently registered trials aimed at understanding these divergent strategies. J. Surg. Oncol. 2017;115:273-280. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Arginina/administración & dosificación , Arginina/deficiencia , Neoplasias/terapia , Animales , Arginina/inmunología , Arginina/metabolismo , Suplementos Dietéticos , Humanos , Neoplasias/inmunología , Neoplasias/metabolismo
10.
Int J Mol Sci ; 16(3): 5334-46, 2015 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-25761239

RESUMEN

Novel therapeutic approaches are emerging to restore dystrophin function in Duchenne Muscular Dystrophy (DMD), a severe neuromuscular disease characterized by progressive muscle wasting and weakness. Some of the molecular therapies, such as exon skipping, stop codon read-through and internal ribosome entry site-mediated translation rely on the type and location of mutations. Hence, their potential applicability worldwide depends on mutation frequencies within populations. In view of this, we compared the mutation profiles of the populations represented in the DMD Leiden Open-source Variation Database with original data from Mexican patients (n = 162) with clinical diagnosis of the disease. Our data confirm that applicability of exon 51 is high in most populations, but also show that differences in theoretical applicability of exon skipping may exist among populations; Mexico has the highest frequency of potential candidates for the skipping of exons 44 and 46, which is different from other populations (p < 0.001). To our knowledge, this is the first comprehensive comparison of theoretical applicability of exon skipping targets among specific populations.


Asunto(s)
Distrofina/genética , Frecuencia de los Genes , Distrofia Muscular de Duchenne/genética , Mutación , Exones , Terapia Genética , Humanos , México , Distrofia Muscular de Duchenne/terapia
11.
Cells ; 13(3)2024 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-38334674

RESUMEN

Different cellular mechanisms influence steatotic liver disease (SLD) progression. The influence of different levels of steatogenic inputs has not been studied in hepatocytes and hepatic stellate cells (HSCs). METHODS: HepG2 hepatocytes and LX-2 HSCs were cultured in mild (MS) and severe (SS) steatogenic conditions. TGF-ß stimulation was also tested for HSCs in control (T) and steatogenic conditions (MS-T and SS-T). Steatosis was stained with Oil Red, and the proliferation was assayed via WST-8 reduction, apoptosis via flow cytometry, and senescence via SA-ß-galactosidase activity. RESULTS: Regarding hepatocytes, steatosis progressively increased; proliferation was lower in MS and SS; and the viability of both conditions significantly decreased at 72 h. Apoptosis increased in MS at 72 h, while it decreased in SS. Senescence increased in MS and diminished in SS. Regarding HSCs, the SS and SS-T groups showed no proliferation, and the viability was reduced in MS at 72 h and in SS and SS-T. The LX-2 cells showed increased apoptosis in SS and SS-T at 24 h, and in MS and MS-T at 72 h. Senescence decreased in MS, SS, and SS-T. CONCLUSIONS: Lipid overload induces differential effects depending on the cell type, the steatogenic input level, and the exposure time. Hepatocytes are resilient to mild steatosis but susceptible to high lipotoxicity. HSCs are sensitive to lipid overload, undergoing apoptosis and lowering senescence and proliferation. Collectively, these data may help explain the development of steatosis and fibrosis in SLD.


Asunto(s)
Hígado Graso , Células Estrelladas Hepáticas , Humanos , Células Estrelladas Hepáticas/metabolismo , Hepatocitos/metabolismo , Hígado Graso/metabolismo , Proliferación Celular , Hiperplasia/metabolismo , Apoptosis , Lípidos
12.
Methods Protoc ; 7(1)2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38392690

RESUMEN

Human placental explants (HPEs) culture has generated significant interest as a valuable in vitro model for studying tissue functions in response to adverse conditions, such as fluctuations in oxygen levels, nutrient availability, exposure to pathogenic microorganisms, and toxic compounds. HPEs offers the advantage of replicating the intricate microenvironment and cell-to-cell communication involved in this critical and transient organ. Although HPEs culture conditions have been extensively discussed, a protocol for assessing the viability and function of HPEs during short-term culture has not been previously outlined. In this study, we have developed a short-term HPEs culture protocol, specifically up to 72 h, and have employed quantitative, semi-quantitative, and qualitative analyses to evaluate tissue viability and function over time. Under our standardized conditions, placental villi explants began to regain their structural properties (the integrity of the trophoblast and villous stroma) and the functionality of the HPEs (production of angiogenic, endocrine, and immunological factors) starting from 48 h of culture. This restoration ensures a suitable environment for several applications. The data presented here can be highly valuable for laboratories aiming to implement an HPEs model, whether in the process of standardization or seeking to enhance and optimize working conditions and timing with placental tissue.

13.
Sci Total Environ ; 945: 173846, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38871316

RESUMEN

Soil bacterial communities play a critical role in shaping soil stability and formation, exhibiting a dynamic interaction with local climate and soil depth. We employed an innovative DNA separation method to characterize microbial assemblages in low-biomass environments such as deserts and distinguish between intracellular DNA (iDNA) and extracellular DNA (eDNA) in soils. This approach, combined with analyses of physicochemical properties and co-occurrence networks, investigated soil bacterial communities across four sites representing diverse climatic gradients (i.e., arid, semi-arid, Mediterranean, and humid) along the Chilean Coastal Cordillera. The separation method yielded a distinctive unimodal pattern in the iDNA pool alpha diversity, increasing from arid to semi-arid climates and decreasing in humid environments, highlighting the rapid feedback of the iDNA community to increasing soil moisture. In the arid region, harsh surface conditions restrict bacterial growth, leading to peak iDNA abundance and diversity occurring in slightly deeper layers than the other sites. Our findings confirmed the association between specialist bacteria and ecosystem-functional traits. We observed transitions from Halomonas and Delftia, resistant to extreme arid environments, to Class AD3 and the genus Bradyrhizobium, associated with plants and organic matter in humid environments. The distance-based redundancy analysis (dbRDA) analysis revealed that soil pH and moisture were the key parameters that influenced bacterial community variation. The eDNA community correlated slightly better with the environment than the iDNA community. Soil depth was found to influence the iDNA community significantly but not the eDNA community, which might be related to depth-related metabolic activity. Our investigation into iDNA communities uncovered deterministic community assembly and distinct co-occurrence modules correlated with unique bacterial taxa, thereby showing connections with sites and key environmental factors. The study additionally revealed the effects of climatic gradients and soil depth on living and dead bacterial communities, emphasizing the need to distinguish between iDNA and eDNA pools.


Asunto(s)
Bacterias , Clima , Microbiota , Microbiología del Suelo , Suelo , Chile , Bacterias/clasificación , Suelo/química , Ecosistema , Monitoreo del Ambiente , Biodiversidad
14.
Hepatol Res ; 43(7): 785-94, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23252661

RESUMEN

AIM: Liver fibrosis results in a disproportion of the hepatic composition and architecture, characterized by a progressive accumulation of fibrillar proteins at the liver parenchyma. Modulated-differential scanning calorimetry (mDSC) is an experimental methodology able to determine the specific thermal signature from any biological substance, based on the variation in heat flow and heat capacity. As these physicochemical properties are directly influenced by compositional and structural changes, we decided to study the thermal behavior of the liver during fibrosis using mDSC. METHODS: Liver fibrosis was induced in rats by bile duct ligation or carbon tetrachloride administration. Degree of liver fibrosis was determined by histological examination using the Masson-trichrome stain, accompanied by hepatic expression of α-smooth muscle actin. The thermal analysis was performed in a modulated-differential scanning calorimeter using 20 mg of fresh liver mass. RESULTS: The liver showed a characteristic thermal signature in control animals, which progressively differed among mild (F1), moderate (F2) and advanced (F3-F4) liver fibrosis. For heat flow, the hepatic thermal signature from F3-F4 rats exhibited significant differences when compared with F1, F2 and controls. In terms of heat capacity, liver specimens provided a specific thermal signature for each stage of disease, characterized by a transition temperature onset at 95°C for controls, whereas in F1, F2 and F3-F4 animals this temperature significantly decreased to 93°C, 84°C and 75°C, respectively. CONCLUSION: Because the liver shows a differential thermal signature according to the degree of fibrosis, mDSC could be a novel tool in the study of liver fibrosis progression.

15.
Sci Total Environ ; 854: 158508, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36063938

RESUMEN

Soil microbial communities regulate a myriad of critical biogeochemical functions in forest ecosystems. Anthropogenic disturbances in natural forests could drive major shifts in plant and microbial communities resulting in substantial biogeochemical alterations. We evaluated the effect of anthropogenic disturbances in the soils of Andean temperate forests with different levels of degradation: i) mature forest (MF), ii) secondary forest (SF), iii) degraded forest (DF), and iv) deforested site converted into a prairie (DP). We quantified total soil carbon, nitrogen and phosphorous (TC, TN, and TP), and available nutrient stocks. The soil microbial community structure (i.e., composition, diversity, and abundance) was assessed under each condition from amplicon sequence variants (ASVs) obtained via NGS-Illumina sequencing and subsequent microbiome analysis. There were no significant differences in TC, TN, and TP across the forested states (MF, SF, DF). The deforested site condition presented significantly higher soil TC, TN, and TP and the lowest C:N, C:P, and N:P ratios. The DP soil microbiome was significantly more diverse in bacteria (D' = 0.47 ± 0.04); and fungi (H' = 5.11 ± 0.33). The bacterial microbiome was dominated by Proteobacteria (45.35 ± 0.89 %), Acidobacteria (20.73 ± 1.48 %), Actinobacteria (12.59 ± 0.34 %), and Bacteroidetes (7.32 ± 0.36 %) phyla in all sites. The soil fungal community was dominated by the phyla Ascomycota (42.11 ± 0.95 %), Mortierellomycota (28.74 ± 2.25 %), Basidiomycota (24.61 ± 0.52), and Mucoromycota (2.06 ± 0.43 %). Yet, there were significant differences at the genus level across conditions. Forest to prairie conversion facilitated the introduction of exotic bacterial and fungal taxa associated with agricultural activities and livestock grazing (∼50 % of DP core microbiome composed of unique ASVs). For example, the ammonia-oxidizing bacteria community emerged as a dominant group in the DP soils, along with a reduction in the ectomycorrhizal fungi community. The surface soil microbial community was surprisingly resistant to forest degradation and did not show a clear succession along the degradation gradient, but it was strongly altered after deforestation.


Asunto(s)
Ascomicetos , Microbiota , Suelo/química , Bosques , Bacterias , Microbiología del Suelo
16.
Front Microbiol ; 14: 1148750, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37362943

RESUMEN

Soil organic matter (SOM) decomposition mechanisms in rainforest ecosystems are governed by biotic and abiotic procedures which depend on available oxygen in the soil. White-rot fungi (WRF) play an important role in the primary decomposition of SOM via enzymatic mechanisms (biotic mechanism), which are linked to abiotic oxidative reactions (e.g., Fenton reaction), where both processes are dependent on reactive oxygen species (ROS) and soil pH variation, which has yet been studied. In humid temperate forest soils, we hypothesize that soil pH is a determining factor that regulates the production and consumption of ROS during biotic and abiotic SOM decomposition. Three soils from different parent materials and WRF inoculum were considered for this study: granitic (Nahuelbuta, Schizophyllum commune), metamorphic (Alerce Costero, Stereum hirsutum), and volcanic-allophanic (Puyehue, Galerina patagonica). CO2 fluxes, lignin peroxidase, manganese peroxidase, and dye-decolorizing peroxidase levels were all determined. Likewise, the production of superoxide anion (O2•-), hydrogen peroxide (H2O2), and hydroxyl radicals (•OH) were assessed in soils microcosms after 36 days of anaerobic incubation with WRF inoculum and induced Fenton reaction under pH variations ranging from 2.5 to 5.1. ROS significantly increased biotic and abiotic CO2 emissions in all tested soils, according to the findings. The highest values (217.45 mg C kg-1) were found during the anaerobic incubation of sterilized and inoculated soils with WRF at a natural pH of 4.5. At pH 4.0, the lowest levels of C mineralization (82 mg C kg-1) were found in Nahuelbuta soil. Enzyme activities showed different trends as pH changed. The Fenton reaction consumed more H2O2 between pH 3 and 4, but less between pH 4.5 and 2.5. The mechanisms that oxidized SOM are extremely sensitive to variations in soil pH and the stability of oxidant radical and non-radical compounds, according to our findings.

17.
Children (Basel) ; 10(3)2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36980039

RESUMEN

OBJECTIVE: The objective of this study was to compare the levels of sedentary behaviour and physical activity in relation to sociodemographic variables of Chilean schoolchildren before and during the COVID-19 pandemic. METHODS: This retrospective study considered a non-random sample of 83 boys and 232 girls, and their respective parents, who attended public schools (n = 119) and private schools (n = 196) in Chile. A self-report instrument was applied that included sociodemographic variables, sedentary behaviour (SB), and physical activity (PA) in the second period of the pandemic in 2021. RESULTS: The main results show that pre-pandemic SB had significant differences when compared between sexes, except for television time. During the pandemic, there was no significant difference in television time or telephone time. There were no significant differences by sex before and during the pandemic. When comparing the SB scores, video game time in boys decreased (p < 0.001), as did video game time in girls (p < 0.001), and computer time in boys (p < 0.001) and girls (p < 0.001). Telephone time increased in boys (p < 0.001) and girls (p < 0.001), as did television time (p < 0.001). Likewise, PA increased in boys (Δ + 9.51min) and girls (Δ + 3.54 min) during the pandemic (p < 0.001). CONCLUSIONS: Both PA and SB underwent changes according to sex before and during the second period of the COVID-19 pandemic in Chilean schoolchildren.

18.
Pathogens ; 12(11)2023 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-38003778

RESUMEN

(1) Background: This study presents the baseline characteristics of a community-level population of people with epilepsy (n = 1975) living in an area endemic for Taenia solium, the pathogen responsible for neurocysticercosis (NCC). (2) Methods: Participants were sequentially enrolled in a clinical cohort from 2007 to 2020 in Tumbes, Peru. All participants provided demographic and clinical history and received clinical evaluations. Diagnostics, including neuroimaging, cysticercosis serologies, and EEG, were obtained where possible. The data presented are from the cross-sectional baseline assessment of cohort participants. (3) Results: Approximately 38% of participants met the criteria for NCC. Those with NCC were more likely to have adult-onset epilepsy, as well as a longer duration of epilepsy, as compared to their counterparts without NCC. Overall, the data indicate a large treatment gap, with only approximately a quarter of the baseline population with prescriptions for anti-seizure medications. (4) Conclusions: These data reveal a high proportion of NCC among people living with epilepsy in these communities, with limited health care resources. At baseline, 74% of the population were not receiving anti-seizure treatments. Further analyses of these data will clarify the natural history of the disease for this population.

19.
Pathogens ; 12(4)2023 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-37111451

RESUMEN

Monoclonal antibody (mAb)-based enzyme-linked immunosorbent assay (ELISA) is a complementary diagnosis technique for neurocysticercosis (NCC), which detects circulating parasite antigen (Ag) indicative of viable infection and Ag levels that correlate well with the parasite burden. In this study, we compared the performance of two Ag-ELISA techniques for the detection of NCC. We assessed the agreement between our in-house TsW8/TsW5 Ag-ELISA and the widely used B158/B60 Ag-ELISA for measuring T. solium antigen levels in the sera from 113 patients with calcified, parenchymal, and subarachnoid NCC. Concordance was demonstrated evaluating the limits of agreement (LoAs) stratified by the type of NCC. Both ELISA's detected 47/48 (97.8%) subarachnoid NCC cases. In parenchymal and calcified NCC, the B158/B60 Ag-ELISA detected 19/24 (79.2%) and 18/41 (43.9%) cases, while the TsW8/TsW5 Ag-ELISA detected 21/24 (87.5%) and 13/41 (31.7%), respectively. Parenchymal and calcified NCC obtained a perfect agreement (100%), indicating that all sample results were within the predicted LoA, while for subarachnoid NCC, the agreement was 89.6%. The high concordance between the assays was confirmed by Lin's concordance coefficient (LCC = 0.97). Patients with viable parenchymal NCC (LCC = 0.95) obtained the highest concordance between assays, followed by subarachnoid NCC (LCC = 0.93) and calcified NCC (LCC = 0.92). The TsW8/TsW5 Ag-ELISA and B158/B60 Ag-ELISA showed high Ag measurement correlations across diverse types of NCC.

20.
Pathogens ; 13(1)2023 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-38251334

RESUMEN

Neurocysticercosis (NCC), the infection of the central nervous system caused by Taenia solium larvae (cysticerci), is a major cause of acquired epilepsy worldwide. Calcification in NCC is the most common neuroimaging finding among individuals with epilepsy in T. solium-endemic areas. We describe the demographic, clinical, and radiological profiles of a large hospital cohort of patients with calcified NCC in Peru (during the period 2012-2022) and compared profiles between patients with and without a previous known diagnosis of viable infection. A total of 524 patients were enrolled (mean age at enrollment: 40.2 ± 15.2 years, mean age at symptom onset: 29.1 ± 16.1 years, 56.3% women). Of those, 415 patients (79.2%) had previous seizures (median time with seizures: 5 years, interquartile range (IQR): 2-13 years; median number of seizures: 7 (IQR: 3-32)), of which 333 (80.2%) had predominantly focal to bilateral tonic-clonic seizures; and 358 (68.3%) used antiseizure medication). Patients had a median number of three calcifications (IQR: 1-7), mostly located in the frontal lobes (79%). In 282 patients (53.8%) there was a previous diagnosis of viable infection, while 242 only had evidence of calcified NCC since their initial neuroimaging. Most patients previously diagnosed with viable infection were male, had previous seizures, had seizures for a longer time, had more calcifications, and had a history of taeniasis more frequently than patients without previously diagnosed viable infection (all p < 0.05). Patients with calcified NCC were heterogeneous regarding burden of infection and clinical manifestations, and individuals who were diagnosed after parasites calcified presented with milder disease manifestations.

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