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1.
Antimicrob Agents Chemother ; : e0014324, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38899927

RESUMEN

In response to the spread of artemisinin (ART) resistance, ART-based hybrid drugs were developed, and their activity profile was characterized against drug-sensitive and drug-resistant Plasmodium falciparum parasites. Two hybrids were found to display parasite growth reduction, stage-specificity, speed of activity, additivity of activity in drug combinations, and stability in hepatic microsomes of similar levels to those displayed by dihydroartemisinin (DHA). Conversely, the rate of chemical homolysis of the peroxide bonds is slower in hybrids than in DHA. From a mechanistic perspective, heme plays a central role in the chemical homolysis of peroxide, inhibiting heme detoxification and disrupting parasite heme redox homeostasis. The hybrid exhibiting slow homolysis of peroxide bonds was more potent in reducing the viability of ART-resistant parasites in a ring-stage survival assay than the hybrid exhibiting fast homolysis. However, both hybrids showed limited activity against ART-induced quiescent parasites in the quiescent-stage survival assay. Our findings are consistent with previous results showing that slow homolysis of peroxide-containing drugs may retain activity against proliferating ART-resistant parasites. However, our data suggest that this property does not overcome the limited activity of peroxides in killing non-proliferating parasites in a quiescent state.

2.
JAMA ; 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38873723

RESUMEN

Importance: Sodium-glucose cotransporter 2 (SGLT-2) inhibitors improve outcomes in patients with type 2 diabetes, heart failure, and chronic kidney disease, but their effect on outcomes of critically ill patients with organ failure is unknown. Objective: To determine whether the addition of dapagliflozin, an SGLT-2 inhibitor, to standard intensive care unit (ICU) care improves outcomes in a critically ill population with acute organ dysfunction. Design, Setting, and Participants: Multicenter, randomized, open-label, clinical trial conducted at 22 ICUs in Brazil. Participants with unplanned ICU admission and presenting with at least 1 organ dysfunction (respiratory, cardiovascular, or kidney) were enrolled between November 22, 2022, and August 30, 2023, with follow-up through September 27, 2023. Intervention: Participants were randomized to 10 mg of dapagliflozin (intervention, n = 248) plus standard care or to standard care alone (control, n = 259) for up to 14 days or until ICU discharge, whichever occurred first. Main Outcomes and Measures: The primary outcome was a hierarchical composite of hospital mortality, initiation of kidney replacement therapy, and ICU length of stay through 28 days, analyzed using the win ratio method. Secondary outcomes included the individual components of the hierarchical outcome, duration of organ support-free days, ICU, and hospital stay, assessed using bayesian regression models. Results: Among 507 randomized participants (mean age, 63.9 [SD, 15] years; 46.9%, women), 39.6% had an ICU admission due to suspected infection. The median time from ICU admission to randomization was 1 day (IQR, 0-1). The win ratio for dapagliflozin for the primary outcome was 1.01 (95% CI, 0.90 to 1.13; P = .89). Among all secondary outcomes, the highest probability of benefit found was 0.90 for dapagliflozin regarding use of kidney replacement therapy among 27 patients (10.9%) in the dapagliflozin group vs 39 (15.1%) in the control group. Conclusion and Relevance: The addition of dapagliflozin to standard care for critically ill patients and acute organ dysfunction did not improve clinical outcomes; however, confidence intervals were wide and could not exclude relevant benefits or harms for dapagliflozin. Trial Registration: ClinicalTrials.gov Identifier: NCT05558098.

3.
Immunology ; 168(2): 217-232, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-35574724

RESUMEN

Essentially all cells are covered with a dense coat of different glycan structures/sugar chains, giving rise to the so-called glycocalyx. Changes in cellular glycosylation are a hallmark of cancer, affecting most of the pathophysiological processes associated with malignant transformation, including tumour immune responses. Glycans are chief macromolecules that define T-cell development, differentiation, fate, activation and signalling. Thus, the diversity of glycans expressed at the surface of T cells constitutes a fundamental molecular interface with the microenvironment by regulating the bilateral interactions between T-cells and cancer cells, fine-tuning the anti-tumour immune response. In this review, we will introduce the power of glycans as orchestrators of T-cell-mediated immune response in physiological conditions and in cancer. We discuss how glycans modulate the glyco-metabolic landscape in the tumour microenvironment, and whether glycans can synergize with immunotherapy as a way of rewiring T-cell effector functions against cancer cells.


Asunto(s)
Neoplasias , Humanos , Polisacáridos , Linfocitos T , Glicosilación , Inmunidad , Microambiente Tumoral
4.
Angew Chem Int Ed Engl ; 58(37): 13066-13079, 2019 09 09.
Artículo en Inglés | MEDLINE | ID: mdl-31290221

RESUMEN

A substantial challenge worldwide is emergent drug resistance in malaria parasites against approved drugs, such as chloroquine (CQ). To address these unsolved CQ resistance issues, only rare examples of artemisinin (ART)-based hybrids have been reported. Moreover, protein targets of such hybrids have not been identified yet, and the reason for the superior efficacy of these hybrids is still not known. Herein, we report the synthesis of novel ART-isoquinoline and ART-quinoline hybrids showing highly improved potencies against CQ-resistant and multidrug-resistant P. falciparum strains (EC50 (Dd2) down to 1.0 nm; EC50 (K1) down to 0.78 nm) compared to CQ (EC50 (Dd2)=165.3 nm; EC50 (K1)=302.8 nm) and strongly suppressing parasitemia in experimental malaria. These new compounds are easily accessible by step-economic C-H activation and copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) click reactions. Through chemical proteomics, putatively hybrid-binding protein targets of the ART-quinolines were successfully identified in addition to known targets of quinoline and artemisinin alone, suggesting that the hybrids act through multiple modes of action to overcome resistance.


Asunto(s)
Antimaláricos/farmacología , Artemisininas/farmacología , Isoquinolinas/farmacología , Malaria/tratamiento farmacológico , Plasmodium/efectos de los fármacos , Animales , Antimaláricos/síntesis química , Antimaláricos/química , Antimaláricos/uso terapéutico , Artemisininas/síntesis química , Artemisininas/química , Artemisininas/uso terapéutico , Química Clic , Resistencia a Múltiples Medicamentos , Humanos , Isoquinolinas/síntesis química , Isoquinolinas/química , Isoquinolinas/uso terapéutico , Ratones
5.
J Zoo Wildl Med ; 48(1): 13-17, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28363079

RESUMEN

Between September 2001 and March 2013, 62 bacterial cultures (37 aerobic and 25 anaerobic) were performed on 37 blood samples from 23 Antillean manatees ( Trichechus manatus manatus) that were kept in captivity at the Brazilian National Center for Research and Conservation of Aquatic Mammals (CMA) in Pernambuco (CMA-PE) and Alagoas (CMA-AL), Brazil. All of the animals sampled exhibited clinical signs at the time of sampling including abscesses (n = 8), debilitation and anorexia (n = 22), and profound lethargy-moribundity (n = 7). The 4 animals with profound lethargy-moribundity died shortly after sampling of unknown causes. Bacteria were isolated from 15/37 (40.5%) and aerobic blood cultures from 13/23 animals (56.5%). None of the anaerobic cultures were positive. Aeromonas caviae , Aeromonas hydrophila , Aeromonas sp., Escherichia coli , Leclercia adecarboxylata , Pantoea agglomerans , Pseudomonas aeruginosa , Pseudomonas stutzeri , Pseudomonas sp., Sphingomonas paucimobilis , coagulase-negative Staphylococcus, and Staphylococcus epidermidis were each found in only one animal; Staphylococcus spp. was found in two; and Vibrio fluvialis in four. Thirteen samples had only one bacteria isolated, one sample had two bacteria, and one sample had three bacteria isolated. Regarding sex, age group, and origin among the manatees examined, 54.5% (6/11) of the females, 58.3% (7/12) of the males, 40% (2/5) of the calves, 66.7% (8/12) of the juveniles, 50% (3/6) of the adults, 55.5% (10/18) at CMA-PE, and 60% (3/5) at CMA-AL were found to be positive for bacterial growth during at least one sampling time. All Antillean manatees were clinically ill. Regarding clinical signs, bacteria were found in 50% (11/22) of blood samples of the animals showing debilitation and anorexia, 1 of 8 (12.5%) of blood samples of the animals showing abscesses, and 3 of 7 (42.9%) of blood samples of the animals showing profound lethargy-moribundity.


Asunto(s)
Bacteriemia/veterinaria , Técnicas Bacteriológicas/veterinaria , Trichechus manatus/sangre , Animales , Bacteriemia/sangre , Femenino , Masculino , Trichechus manatus/microbiología
6.
Biochim Biophys Acta ; 1840(7): 2262-71, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24641823

RESUMEN

BACKGROUND: Plant lectins have attracted great interest in cancer studies due to their antitumor activities. These proteins or glycoproteins specifically and reversibly bind to different types of carbohydrates or glycoproteins. Breast cancer, which presents altered glycosylation of cell surface glycoproteins, is one of the most frequent malignant diseases in women. In this work, we describe the effect of the lectin Bauhinia forficata lectin (BfL), which was purified from B. forficata Link subsp. forficata seeds, on the MCF7 human breast cancer cellular line, investigating the mechanisms involved in its antiproliferative activity. METHODS: MCF7 cells were treated with BfL. Viability and adhesion alterations were evaluated using flow cytometry and western blotting. RESULTS: BfL inhibited the viability of the MCF7 cell line but was ineffective on MDA-MB-231 and MCF 10A cells. It inhibits MCF7 adhesion on laminin, collagen I and fibronectin, decreases α1, α6 and ß1 integrin subunit expression, and increases α5 subunit expression. BfL triggers necrosis and secondary necrosis, with caspase-9 inhibition. It also causes deoxyribonucleic acid (DNA) fragmentation, which leads to cell cycle arrest in the G2/M phase and a decrease in the expression of the regulatory proteins pRb and p21. CONCLUSION: BfL shows selective cytotoxic effect and adhesion inhibition on MCF7 breast cancer cells. GENERAL SIGNIFICANCE: Cell death induction and inhibition of cell adhesion may contribute to understanding the action of lectins in breast cancer.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Adhesión Celular/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Lectinas/farmacología , Bauhinia/química , Neoplasias de la Mama/patología , Supervivencia Celular/efectos de los fármacos , Femenino , Humanos , Integrinas/metabolismo , Lectinas/química , Células MCF-7
7.
Cell Physiol Biochem ; 36(4): 1467-79, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26160428

RESUMEN

BACKGROUND/AIMS: Several studies have been performed to unravel the association between diabetes and increased susceptibility to infection. This study aimed to investigate the effect of insulin on the local environment after cecal ligation and puncture (CLP) in rats. METHODS: Diabetic (alloxan, 42 mg/kg i.v., 10 days) and non-diabetic (control) male Wistar rats were subjected to a two-puncture CLP procedure and 6 h later, the following analyses were performed: (a) total and differential cell counts in peritoneal lavage (PeL) and bronchoalveolar lavage (BAL) fluids; (b) quantification of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL- 6, IL-10 and cytokine-induced neutrophil chemoattractant (CINC)-1 and CINC-2 in the PeL and BAL fluids by enzyme-linked immunosorbent assay (ELISA); (c) total leukocyte count using a veterinary hematology analyzer and differential leukocyte counts on stained slides; (d) biochemical parameters (urea, creatinine, alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) by colorimetric analyses); and (e) lung, kidney, and liver morphological analyses (hematoxylin and eosin staining). RESULTS: Relative to controls, non-diabetic and diabetic CLP rats exhibited an increased in the concentration of IL-1ß, IL-6, IL-10, CINC-1, and CINC-2 and total and neutrophil in the PeL fluid. Treatment of these animals with neutral protamine Hagedorn insulin (NPH, 1IU and 4IU, respectively, s.c.), 2 hours before CLP procedure, induced an increase on these cells in the PeL fluid but it did not change cytokine levels. The levels of ALT, AST, ALP, and urea were higher in diabetic CLP rats than in non-diabetic CLP rats. ALP levels were higher in diabetic sham rats than in non-diabetic sham rats. Treatment of diabetic rats with insulin completely restored ALT, AST, and ALP levels. CONCLUSION: These results together suggest that insulin attenuates liver dysfunction during early two-puncture CLP-induced peritoneal inflammation in diabetic rats.


Asunto(s)
Diabetes Mellitus Tipo 1/tratamiento farmacológico , Diabetes Mellitus Tipo 1/fisiopatología , Hipoglucemiantes/uso terapéutico , Insulina Isófana/uso terapéutico , Hígado/efectos de los fármacos , Hígado/fisiopatología , Aloxano , Animales , Glucemia/análisis , Citocinas/análisis , Diabetes Mellitus Tipo 1/inducido químicamente , Masculino , Ratas , Ratas Wistar , Aumento de Peso/efectos de los fármacos
8.
Chromosome Res ; 20(5): 481-92, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22740047

RESUMEN

All living organisms require accurate mechanisms to faithfully inherit their genetic material during cell division. The centromere is a unique locus on each chromosome that supports a multiprotein structure called the kinetochore. During mitosis, the kinetochore is responsible for connecting chromosomes to spindle microtubules, allowing faithful segregation of the duplicated genome. In most organisms, centromere position and function is not defined by the local DNA sequence context but rather by an epigenetic chromatin-based mechanism. Centromere protein A (CENP-A) is central to this process, as chromatin assembled from this histone H3 variant is essential for assembly of the centromere complex, as well as for its epigenetic maintenance. As a major determinant of centromere function, CENP-A assembly requires tight control, both in its specificity for the centromere and in timing of assembly. In the last few years, there have been several new insights into the molecular mechanism that allow this process to occur. We will review these here and discuss the general implications of the mechanism of cell cycle coupling of centromere inheritance.


Asunto(s)
Autoantígenos/metabolismo , Centrómero/metabolismo , Proteínas Cromosómicas no Histona/metabolismo , Epigénesis Genética , Animales , Secuencia de Bases , Puntos de Control del Ciclo Celular , Proteína A Centromérica , Ensamble y Desensamble de Cromatina , Segregación Cromosómica , Hongos/metabolismo , Histonas/metabolismo , Humanos , Patrón de Herencia , Modelos Genéticos , Mapeo de Interacción de Proteínas , Especificidad por Sustrato
9.
J Agric Food Chem ; 71(42): 15766-15773, 2023 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-37843073

RESUMEN

A reliable method using a QuEChERS approach and liquid chromatography coupled to Q-Orbitrap mass spectrometry was optimized and validated for the quantification of 20 growth promoters in bovine serum. The recoveries ranged from 91.4-114.1%, relative standard deviations varied between 0.3-4.0%, and CCα values were between 0.023-0.350 µg L-1. The developed method was applied in an in vivo study using steers, which were intramuscularly treated with commercial injections containing stanozolol. A rapid metabolization was observed, with a detection window ranging from 3 to 10 days. The stability of incurred stanozolol was confirmed after 240 days at -20 °C and also after 5 freeze-thaw cycles. To the best of our knowledge, this is the first work in which an in vivo study was performed to support the monitoring of stanozolol in bovine serum. In addition, the use of Q-Orbitrap high-resolution mass spectrometry allows for retrospective analysis from a surveillance perspective.


Asunto(s)
Estanozolol , Cromatografía Líquida de Alta Presión/métodos , Estudios Retrospectivos , Espectrometría de Masas/métodos , Cromatografía Liquida
10.
Pharmaceuticals (Basel) ; 15(1)2022 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-35056117

RESUMEN

Plasmodium has evolved to regulate the levels and oxidative states of iron protoporphyrin IX (Fe-PPIX). Antimalarial endoperoxides such as 1,2,4-trioxane artemisinin and 1,2,4-trioxolane arterolane undergo a bioreductive activation step mediated by heme (FeII-PPIX) but not by hematin (FeIII-PPIX), leading to the generation of a radical species. This can alkylate proteins vital for parasite survival and alkylate heme into hematin-drug adducts. Heme alkylation is abundant and accompanied by interconversion from the ferrous to the ferric state, which may induce an imbalance in the iron redox homeostasis. In addition to this, hematin-artemisinin adducts antagonize the spontaneous biomineralization of hematin into hemozoin crystals, differing strikingly from artemisinins, which do not directly suppress hematin biomineralization. These hematin-drug adducts, despite being devoid of the peroxide bond required for radical-induced alkylation, are powerful antiplasmodial agents. This review addresses our current understanding of Fe-PPIX as a bioreductive activator and molecular target. A compelling pharmacological model is that by alkylating heme, endoperoxide drugs can cause an imbalance in the iron homeostasis and that the hematin-drug adducts formed have strong cytocidal effects by possibly reproducing some of the toxifying effects of free Fe-PPIX. The antiplasmodial phenotype and the mode of action of hematin-drug adducts open new possibilities for reconciliating the mechanism of endoperoxide drugs and for malaria intervention.

11.
Front Microbiol ; 13: 859732, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35432251

RESUMEN

Genital mycoplasmas (GM), such as Mycoplasma hominis, Mycoplasma genitalium, Ureaplasma parvum, and Ureaplasma urealyticum are commonly associated with spontaneous preterm labor (SPTL), spontaneous preterm birth (PTB), and preterm prelabor rupture of membranes (PPROM). This study determined the association between GM and such adverse pregnancy outcomes. We searched for studies published 1980-2019 in MEDLINE, EMBASE, and Web of Science. Studies were eligible when GM was detected during pregnancy. We included 93 and 51 studies in determining the prevalence and the inflammatory biomarkers associated with GM, respectively, using the "metafor" package within R. The protocol was registered with PROSPERO (registration no. CRD42016047297). Women with the studied adverse pregnancy outcomes had significantly higher odds of presence with GM compared to women who delivered at term. For PTB, the odds ratios were: M. hominis (OR: 2.25; CI: 1.35-3.75; I 2: 44%), M. genitalium (OR: 2.04; CIL 1.18-3.53; I 2: 20%), U. parvum (OR: 1.75; CI: 1.47-2.07; I 2: 0%), U. urealyticum (OR: 1.50; CI: 1.08-2.07; I 2: 58%). SPTL had significantly higher odds with M. hominis (OR: 1.96; CI: 1.19-3.23; I 2: 1%) or U. urealyticum (OR: 2.37; CI: 1.20-4.70; I 2: 76%) compared to women without SPTL. Women with PPROM had significantly higher odds with M. hominis (OR: 2.09; CI: 1.42-3.08; I 2: 0%) than women without PPROM. However, our subgroup analysis based on the diagnostic test and the sample used for detecting GM showed a higher prevalence of GM in maternal samples than in fetal samples. GM presence of the cervix and vagina was associated with lower odds of PTB and preterm labor (PTL). In contrast, GM presence in the AF, fetal membrane, and placenta was associated with increased odds of PTB and PTL. However, genital mycoplasmas may not elicit the massive inflammation required to trigger PTB. In conclusion, GM presence in the fetal tissues was associated with significantly increased odds of PTB and PTL.

12.
J Agric Food Chem ; 70(15): 4749-4754, 2022 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-35380851

RESUMEN

An in vivo study was performed in order to evaluate the depletion time of stanozolol and its main metabolites using naturally incurred urine sample collected after the administration of intramuscular injections in 12 steers. A stability study was also carried out to investigate the influence of the storage period and the freeze-thaw cycles. A fast parent drug metabolization was observed, because within 6 h after drug administration, the signal of the metabolite 16ß-hydroxystanozolol was predominant. After the second drug administration, a detection window of 17 days was obtained. The stability was studied using ANOVA, in which a storage condition of -20 °C proved stable during 240 days, which was also confirmed after 5 freeze-thaw cycles.


Asunto(s)
Estanozolol , Animales , Bovinos , Cromatografía Líquida de Alta Presión , Inyecciones Intramusculares , Estanozolol/orina
13.
J Agric Food Chem ; 69(28): 7990-7996, 2021 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-34227807

RESUMEN

In this work, 37 growth promoters were quantitatively determined in bovine urine using a QuEChERS approach with acetonitrile, NaCl, and MgSO4:PSA for sample extraction. The analytes were separated and detected by liquid chromatography coupled to hybrid high-resolution mass spectrometry. The method was validated in accordance with the Decision 657/2002/EC guidelines, in which recoveries fell within the range 84-113%, relative standard varied between 2 and 32%, and detection limit between 0.1 and 2.5 µg L-1. An adequate performance was evidenced during a proficiency test evaluation, and the developed method has been applied to routine analysis of growth promoters in Brazil. A highlight is the easiness of sample extraction combined with a quantitative determination of forbidden drugs using high-resolution mass spectrometry, which enables retrospective analysis in a surveillance perspective.


Asunto(s)
Cromatografía Líquida de Alta Presión , Animales , Brasil , Bovinos , Cromatografía Liquida , Espectrometría de Masas , Estudios Retrospectivos
14.
Curr Biol ; 31(18): 4038-4051.e7, 2021 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-34314679

RESUMEN

The frequency of egg aneuploidy and trisomic pregnancies increases with maternal age. To what extent individual approaches can delay the "maternal age effect" is unclear because multiple causes contribute to chromosomal abnormalities in mammalian eggs. We propose that ovulation frequency determines the physiological aging of oocytes, a key aspect of which is the ability to accurately segregate chromosomes and produce euploid eggs. To test this hypothesis, ovulations were reduced using successive pregnancies, hormonal contraception, and a pre-pubertal knockout mouse model, and the effects on chromosome segregation and egg ploidy were examined. We show that each intervention reduces chromosomal abnormalities in eggs of aged mice, suggesting that ovulation reduction delays oocyte aging. The protective effect can be partly explained by retention of chromosomal Rec8-cohesin that maintains sister chromatid cohesion in meiosis. In addition, single-nucleus Hi-C (snHi-C) revealed deterioration in the 3D chromatin structure including an increase in extruded loop sizes in long-lived oocytes. Artificial cleavage of Rec8 is sufficient to increase extruded loop sizes, suggesting that cohesin complexes maintaining cohesion restrict loop extrusion. These findings suggest that ovulation suppression protects against Rec8 loss, thereby maintaining both sister chromatid cohesion and 3D chromatin structure and promoting production of euploid eggs. We conclude that the maternal age effect can be delayed in mice. An implication of this work is that long-term ovulation-suppressing conditions can potentially reduce the risk of aneuploid pregnancies at advanced maternal age.


Asunto(s)
Meiosis , Inhibición de la Ovulación , Animales , Proteínas de Ciclo Celular/genética , Aberraciones Cromosómicas , Segregación Cromosómica , Femenino , Mamíferos , Edad Materna , Ratones , Oocitos/fisiología
15.
J Agric Food Chem ; 69(19): 5528-5535, 2021 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-33970002

RESUMEN

This work involved a systematic comparison between serum and urine for the monitoring of anabolic androgenic steroids in livestock. Incurred samples were collected over 120 days from crossbred steers treated with intramuscular injections containing boldenone undecylenate. Independent high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) methods were used for the assessment of the respective detection windows, which were larger for serum samples. Both matrices presented adequate performance in terms of long-term stability, assessed using an isochronous approach during 196 days at -20 °C and for five freeze-thaw cycles. The effectiveness of the enzymatic hydrolysis reaction using Helix pomatia juice was also compared. The calculated concentrations in serum samples were not statistically influenced by the deconjugation reaction. On the other hand, urine hydrolysis conditions were studied using a 33 Box-Behnken Design, in which a central point condition led to a satisfactory deconjugation performance. It could be observed that serum exhibited equivalent or better performance than urine for most of the evaluated criteria; thus, its inclusion in the regulatory analysis of boldenone in cattle is supported.


Asunto(s)
Anabolizantes , Espectrometría de Masas en Tándem , Animales , Bovinos , Cromatografía Líquida de Alta Presión , Hidrólisis , Testosterona/análogos & derivados
16.
PLoS One ; 16(2): e0246891, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33577592

RESUMEN

BACKGROUND: During pneumonia, normal alveolar areas coexist adjacently with consolidated areas, and high inspiratory efforts may predispose to lung damage. To date, no study has evaluated different degrees of effort during Biphasic positive airway pressure (BIVENT) on lung and diaphragm damage in experimental pneumonia, though largely used in clinical setting. We aimed to evaluate lung damage, genes associated with ventilator-induced lung injury (VILI) and diaphragmatic injury, and blood bacteria in pressure-support ventilation (PSV), BIVENT with low and high inspiratory efforts in experimental pneumonia. MATERIAL AND METHODS: Twenty-eight male Wistar rats (mean ± SD weight, 333±78g) were submitted Pseudomonas aeruginosa-induced pneumonia. After 24-h, animals were ventilated for 1h in: 1) PSV; 2) BIVENT with low (BIVENTLow-Effort); and 3) BIVENT with high inspiratory effort (BIVENTHigh-Effort). BIVENT was set at Phigh to achieve VT = 6 ml/kg and Plow at 5 cmH2O (n = 7/group). High- and low-effort conditions were obtained through anaesthetic infusion modulation based on neuromuscular drive (P0.1). Lung mechanics, histological damage score, blood bacteria, and expression of genes related to VILI in lung tissue, and inflammation in diaphragm tissue. RESULTS: Transpulmonary peak pressure and histological damage score were higher in BIVENTHigh-Effort compared to BIVENTLow-Effort and PSV [16.1 ± 1.9cmH2O vs 12.8 ± 1.5cmH2O and 12.5 ± 1.6cmH2O, p = 0.015, and p = 0.010; median (interquartile range) 11 (9-13) vs 7 (6-9) and 7 (6-9), p = 0.021, and p = 0.029, respectively]. BIVENTHigh-Effort increased interleukin-6 expression compared to BIVENTLow-Effort (p = 0.035) as well as expressions of cytokine-induced neutrophil chemoattractant-1, amphiregulin, and type III procollagen compared to PSV (p = 0.001, p = 0.001, p = 0.004, respectively). Tumour necrosis factor-α expression in diaphragm tissue and blood bacteria were higher in BIVENTHigh-Effort than BIVENTLow-Effort (p = 0.002, p = 0.009, respectively). CONCLUSION: BIVENT requires careful control of inspiratory effort to avoid lung and diaphragm damage, as well as blood bacteria. P0.1 might be considered a helpful parameter to optimize inspiratory effort.


Asunto(s)
Presión de las Vías Aéreas Positiva Contínua/efectos adversos , Pulmón/patología , Neumonía Bacteriana/terapia , Infecciones por Pseudomonas/terapia , Pseudomonas aeruginosa/aislamiento & purificación , Lesión Pulmonar Inducida por Ventilación Mecánica/etiología , Animales , Diafragma/patología , Modelos Animales de Enfermedad , Masculino , Neumonía Bacteriana/patología , Infecciones por Pseudomonas/patología , Ratas Wistar , Volumen de Ventilación Pulmonar , Lesión Pulmonar Inducida por Ventilación Mecánica/patología
17.
Chromosoma ; 118(5): 567-74, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19590885

RESUMEN

Centromeres, the chromosomal loci that form the sites of attachment for spindle microtubules during mitosis, are identified by a unique chromatin structure generated by nucleosomes containing the histone H3 variant CENP-A. The apparent epigenetic mode of centromere inheritance across mitotic and meiotic divisions has generated much interest in how CENP-A assembly occurs and how structurally divergent centromeric nucleosomes can specify the centromere complex. Although a substantial number of proteins have been implicated in centromere assembly, factors that can bind CENP-A specifically and deliver nascent protein to the centromere were, thus far, lacking. Several recent reports on experiments in fission yeast and human cells have now shown significant progress on this problem. Here, we discuss these new developments and their implications for epigenetic centromere inheritance.


Asunto(s)
Autoantígenos/metabolismo , Centrómero/fisiología , Proteínas Cromosómicas no Histona/metabolismo , Proteínas Adaptadoras Transductoras de Señales/fisiología , Animales , Proteínas Portadoras/fisiología , Ciclo Celular/fisiología , Proteína A Centromérica , Cromatina/fisiología , Humanos , Proteínas de Schizosaccharomyces pombe/fisiología
18.
J Biomed Biotechnol ; 2010: 179817, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20617135

RESUMEN

Lectins, proteins which selectively recognize carbohydrates, have been used in histochemistry for the evaluation of changes in glycosylation in processes of cellular differentiation and/or dedifferentiation. Cratylia mollis seed lectins (Cramoll 1,4 and Cramoll 3), conjugated to horseradish peroxidase, were used as histochemical probes in human prostate tissues: normal (NP), hyperplasia (BPH), and prostate carcinoma (PCa). The staining pattern of Con-A and Cramoll 1,4 in BPH was more intense than in NP. These lectins also showed staining differences between BPH and PCa; the latter showing decreased staining intensity with an increased degree of malignancy. PNA and Cramoll 3 stained epithelial cells similarly in all diagnoses although they did present intense staining of PCa glands lumen. Corpora amylacea were not differentially recognized by any of the lectins. Cramoll 1,4 and Cramoll 3 seed lectins present themselves as candidates for histochemical probes for prostate pathologies when compared to commercial lectins such as Con-A and PNA.


Asunto(s)
Histocitoquímica/métodos , Lectinas de Plantas/química , Próstata/metabolismo , Hiperplasia Prostática/metabolismo , Neoplasias de la Próstata/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Concanavalina A/química , Concanavalina A/metabolismo , Fabaceae , Glicosilación , Humanos , Masculino , Persona de Mediana Edad , Aglutinina de Mani/química , Aglutinina de Mani/metabolismo , Lectinas de Plantas/metabolismo , Semillas/química , Estadísticas no Paramétricas
19.
J Cell Biol ; 219(4)2020 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-32328639

RESUMEN

Cohesin is essential for genome folding and inheritance. In somatic cells, these functions are both mediated by Scc1-cohesin, which in mitosis is released from chromosomes by Wapl and separase. In mammalian oocytes, cohesion is mediated by Rec8-cohesin. Scc1 is expressed but neither required nor sufficient for cohesion, and its function remains unknown. Likewise, it is unknown whether Wapl regulates one or both cohesin complexes and chromosome segregation in mature oocytes. Here, we show that Wapl is required for accurate meiosis I chromosome segregation, predominantly releases Scc1-cohesin from chromosomes, and promotes production of euploid eggs. Using single-nucleus Hi-C, we found that Scc1 is essential for chromosome organization in oocytes. Increasing Scc1 residence time on chromosomes by Wapl depletion leads to vermicelli formation and intra-loop structures but, unlike in somatic cells, does not increase loop size. We conclude that distinct cohesin complexes generate loops and cohesion in oocytes and propose that the same principle applies to all cell types and species.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Proteínas Cromosómicas no Histona/metabolismo , Cromosomas de los Mamíferos/metabolismo , Proteínas de Unión al ADN/metabolismo , Oocitos/metabolismo , Proteínas/metabolismo , Animales , Células Cultivadas , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Cohesinas
20.
Stem Cells Transl Med ; 9(10): 1244-1256, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32538526

RESUMEN

Silicosis is a pneumoconiosis caused by inhaled crystalline silica microparticles, which trigger inflammatory responses and granuloma formation in pulmonary parenchyma, thus affecting lung function. Although systemic administration of mesenchymal stromal cells (MSCs) ameliorates lung inflammation and attenuates fibrosis in experimental silicosis, it does not reverse collagen deposition and granuloma formation. In an attempt to improve the beneficial effects of MSCs, magnetic targeting (MT) has arisen as a potential means of prolonging MSC retention in the lungs. In this study, MSCs were incubated with magnetic nanoparticles and magnets were used for in vitro guidance of these magnetized MSCs and to enhance their retention in the lungs in vivo. In vitro assays indicated that MT improved MSC transmigration and expression of chemokine receptors. In vivo, animals implanted with magnets for 48 hours had significantly more magnetized MSCs in the lungs, suggesting improved MSC retention. Seven days after magnet removal, silicotic animals treated with magnetized MSCs and magnets showed significant reductions in static lung elastance, resistive pressure, and granuloma area. In conclusion, MT is a viable technique to prolong MSC retention in the lungs, enhancing their beneficial effects on experimentally induced silicosis. MT may be a promising strategy for enhancing MSC therapies for chronic lung diseases.


Asunto(s)
Pulmón/patología , Magnetismo/métodos , Células Madre Mesenquimatosas/patología , Nanopartículas/metabolismo , Silicosis/terapia , Animales , Modelos Animales de Enfermedad , Femenino , Humanos , Ratones , Silicosis/fisiopatología
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