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1.
Toxicol Appl Pharmacol ; 459: 116344, 2023 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-36526072

RESUMEN

P-glycoprotein (P-gp, encoded by the ABCB1 gene) and breast cancer resistance protein (BCRP/ABCG2) are efflux multidrug resistance (MDR) transporters localized at the syncytiotrophoblast barrier of the placenta and protect the conceptus from drug and toxin exposure throughout pregnancy. Infection is an important modulator of MDR expression and function. This review comprehensively examines the effect of infection on the MDR transporters, P-gp and BCRP in the placenta. Infection PAMPs such as bacterial lipopolysaccharide (LPS) and viral polyinosinic-polycytidylic acid (poly I:C) and single-stranded (ss)RNA, as well as infection with Zika virus (ZIKV), Plasmodium berghei ANKA (modeling malaria in pregnancy - MiP) and polymicrobial infection of intrauterine tissues (chorioamnionitis) all modulate placental P-gp and BCRP at the levels of mRNA, protein and or function; with specific responses varying according to gestational age, trophoblast type and species (human vs. mice). Furthermore, we describe the expression and localization profile of Toll-like receptor (TLR) proteins of the innate immune system at the maternal-fetal interface, aiming to better understand how infective agents modulate placental MDR. We also highlight important gaps in the field and propose future research directions. We conclude that alterations in placental MDR expression and function induced by infective agents may not only alter the intrauterine biodistribution of important MDR substrates such as drugs, toxins, hormones, cytokines, chemokines and waste metabolites, but also impact normal placentation and adversely affect pregnancy outcome and maternal/neonatal health.


Asunto(s)
Infección por el Virus Zika , Virus Zika , Embarazo , Femenino , Humanos , Ratones , Animales , Placenta/metabolismo , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/genética , Distribución Tisular , Proteínas de Neoplasias/genética , Resistencia a Múltiples Medicamentos , Proteínas de Transporte de Membrana/metabolismo
2.
Appetite ; 174: 106012, 2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-35367482

RESUMEN

Estrogens reduce 0.3 M NaCl intake and palatability in a widely used model of essential hypertension, the spontaneously hypertensive rats (SHRs). Here we investigated whether the inhibitory effects of ß-estradiol (E2, 10 µg/kg b.w. subcutaneously for 8 days) on water deprived partially-rehydrated (WD-PR) ovariectomized (OVX) adult female SHRs (fSHRs, n = 4-10/group) are related to interferences on brain angiotensin II AT1 receptors (AT1r). After WD-PR, E2 reduced 0.3 M NaCl intake (1.3 ± 0.6, vs. vehicle: 3.5 ± 1.2 ml/30 min), the number of hedonic responses to intraoral NaCl infusion (57 ± 11, vs. vehicle: 176 ± 32/min), and the relative angiotensin AT1r (Agtr1a) mRNA expression in the hypothalamus. Losartan (AT1r antagonist, 100 µg) intracerebroventricularly in OVX fSHRs treated with vehicle subcutaneously abolished 0.3 M NaCl intake (0.1 ± 0.1 ml/30 min) and only transiently reduced hedonic responses to intraoral NaCl. Losartan combined with E2 decreased the number of hedonic and increased the number of aversive responses to intraoral NaCl and abolished 0.3 M NaCl intake. E2 also reduced the pressor and dipsogenic responses to intracerebroventricular angiotensin II. The results suggest that AT1r activation increases palatability and induces NaCl intake in WD-PR fSHRs. E2 reduced hypothalamic Agtr1a mRNA expression, which may account for the effects of E2 on NaCl intake and palatability and intracerebroventricular angiotensin II-induced pressor and dipsogenic responses in OVX fSHRs. Future studies considering natural fluctuations in estrogen secretion might help to determine the degree of such interference in brain neuronal activity.


Asunto(s)
Angiotensina II , Losartán , Angiotensina II/farmacología , Animales , Estradiol/farmacología , Femenino , Humanos , Losartán/farmacología , ARN Mensajero , Ratas , Ratas Endogámicas SHR , Receptor de Angiotensina Tipo 1/genética , Cloruro de Sodio
3.
Horm Behav ; 130: 104952, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33647281

RESUMEN

Spontaneously hypertensive rats (SHRs) ingest more NaCl than normotensive strains. Here we investigated NaCl intake and taste reactivity in adult male SHRs and normotensive Holtzman rats treated or not with AT1 receptor antagonist centrally in euhydrated condition and after fluid depletion. Taste reactivity was measured by the number of orofacial expressions to intra-oral infusions of 0.3 M NaCl. In euhydrated condition, intra-oral infusions of 0.3 M NaCl produced greater number of hedonic responses in SHRs than in normotensive rats, without differences in the number of aversive responses. Compared to euhydrated condition, the treatment with the diuretic furosemide + low dose of captopril (angiotensin converting enzyme blocker) increased the number of hedonic and reduced the number of aversive responses to intra-oral NaCl in normotensive rats, without changing the number of hedonic or aversive responses in SHRs. Losartan (AT1 receptor antagonist, 100 ng/1 µl) injected intracerebroventricularly in SHRs abolished 0.3 M NaCl intake induced by water deprivation + partial rehydration, whereas only transiently (first 30 min of the 60 min test) reduced hedonic responses, without changes in aversive responses to intra-oral NaCl. Losartan intracerebroventricularly also only transiently (first 30 min) reduced the number of hedonic responses to intra-oral NaCl in euhydrated SHRs. The results suggest that NaCl palatability is increased and independent from body fluid balance in SHRs. The results also suggest that central AT1 receptors are part of the mechanisms activated to increase NaCl intake and palatability in SHRs. A partial dissociation between NaCl intake and palatability in SHRs is also suggested.


Asunto(s)
Captopril , Sodio , Animales , Captopril/farmacología , Furosemida/farmacología , Losartán/farmacología , Masculino , Ratas , Ratas Endogámicas SHR
4.
Mol Divers ; 25(1): 55-66, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31900682

RESUMEN

Cancer is one of the leading causes of death worldwide and requires intense and growing research investments from the public and private sectors. This is expected to lead to the development of new medicines. A determining factor in this process is the structural understanding of molecules with potential anticancer properties. Since the major compounds used in cancer therapies fail to encompass every spectrum of this disease, there is a clear need to research new molecules for this purpose. As it follows, we have studied the class of quinolinones that seem effective for such therapy. This paper describes the structural elucidation of a novel dihydroquinoline by single-crystal X-ray diffraction and spectroscopy characterization. Topology studies were carried through Hirshfeld surfaces analysis and molecular electrostatic potential map; electronic stability was evaluated from the calculated energy of frontier molecular orbitals. Additionally, in silico studies by molecular docking indicated that this dihydroquinoline could act as an anticancer agent due to their higher binding affinity with human aldehyde dehydrogenase 1A1 (ALDH 1A1). Tests in vitro were performed for VERO (normal human skin keratinocytes), B16F10 (mouse melanoma), and MDA-MB-231 (metastatic breast adenocarcinoma), and the results certified that compound as a potential anticancer agent. A Dihydroquinoline derivative was tested against three cancer cell lines and the results attest that compound as potential anticancer agent.


Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Neoplasias/tratamiento farmacológico , Quinolinas/química , Quinolinas/farmacología , Animales , Línea Celular , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Chlorocebus aethiops , Cristalografía por Rayos X/métodos , Ensayos de Selección de Medicamentos Antitumorales/métodos , Compuestos Heterocíclicos/química , Compuestos Heterocíclicos/farmacología , Humanos , Ratones , Modelos Moleculares , Simulación del Acoplamiento Molecular/métodos , Quinolonas/química , Quinolonas/farmacología , Relación Estructura-Actividad , Células Vero
5.
Appetite ; 158: 105037, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33186624

RESUMEN

The renin-angiotensin system (RAS) controls hypertonic NaCl intake driven by sodium appetite. Here we investigated whether the antagonism of RAS interferes with hedonic and aversive orofacial motor responses, or palatability, to intraoral infusion of 0.3 M NaCl (hNaCl). Adult rats were depleted of sodium by combined sc injection of furosemide and 24 h removal of ambient sodium. In experiment 1, losartan (AT1 angiotensin II receptor antagonist, intracerebroventricular, 200 µg/µl), produced a three-fold increase in aversive orofacial motor responses to hNaCl. Losartan also suppressed hNaCl intake recorded immediately thereafter. In experiment 2, each animal had repeated recordings of hNaCl intake and orofacial responses to hNaCl distributed for 180 min. Paired recordings of intake and orofacial responses occurred within five successive blocks after the recordings of only orofacial responses when the animals were still sodium deplete (block zero). Captopril (angiotensin converting enzyme blocker, intraperitoneal, 30 mg/kg) inhibited by 75% the hedonic orofacial responses to hNaCl in blocks zero and 1. The hedonic responses to captopril remained the same throughout blocks, but became similar to vehicle from blocks 2 to 5. There was no difference in aversive responses to 0.3 M NaCl between captopril and vehicle. Captopril produced a 70-100% inhibition of hNaCl intake in blocks 1 to 5. The results suggest that angiotensin II acts in the brain increasing the palatability of hypertonic sodium during the consummatory phase of sodium appetite.


Asunto(s)
Sistema Renina-Angiotensina , Sodio , Animales , Apetito , Captopril/farmacología , Losartán/farmacología , Ratas , Cloruro de Sodio
6.
Appetite ; 155: 104822, 2020 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-32795566

RESUMEN

Behavioral sensitization occurs during sodium appetite (expressed as sodium intake to compensate for depleted sodium) and need-free sodium intake (expressed as daily overnight sodium intake in excess of dietary sodium need). Previously, we found that a slow-onset sodium appetite protocol cross-sensitized need-free sucrose intake in sucrose-naïve adult rats. That is, a history of sodium depletion elevated later sucrose intake. The objective of the present work was, first, to investigate whether a protocol that evokes a rapid-onset (within 2 h) sodium appetite using furosemide along with a low dose captopril (Furo/Cap), also cross-sensitizes sucrose intake. Then, we investigated whether 1) sensitization of need-free 0.3 M NaCl intake interacts with need-free sucrose intake, and 2) MK-801, a glutamate NMDA receptor antagonist, inhibits cross-sensitization of sucrose intake. Groups received 3-4 Furo/Cap or vehicle treatments with 48/72-h intervals. We investigated sucrose intake in hydrated and fed conditions for 2 h/day for 5 days, starting 6-10 days after the last Furo/Cap treatment. Episodes of Furo/Cap sensitized need-free sodium intake, as expected. Similar to our prior work, the rapid-onset Furo/Cap protocol cross-sensitized sucrose intake in sucrose-naïve rats and had no persistent effect on blood biochemistry. MK-801 treatment along with Furo/Cap injections appeared to prevent cross-sensitization of sucrose consumption. Sucrose intake tests unexpectedly reduced sensitized need-free sodium intake. However, MK-801 treatment allowed a rebound in need-free sodium intake subsequent to the last sucrose intake test. The results suggest that plasticity in glutamatergic mechanisms mediate inverse and reciprocal interactions between the production of sodium appetite and sucrose intake.


Asunto(s)
Apetito , Sodio en la Dieta , Animales , Diuréticos/farmacología , Ratas , Ratas Sprague-Dawley , Sodio , Azúcares
7.
Lupus ; 28(11): 1368-1377, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31558100

RESUMEN

OBJECTIVE: Studies have been conducted to determine the causal factors and clinical consequences of non-adherence to treatment in systemic lupus erythematosus (SLE). However, no interventions have been performed to increase drug adherence. Our objective was to assess the effectiveness of pharmaceutical care (PC) for drug treatment adherence in lupus nephritis (LN). METHODS: This was a randomized clinical trial (pragmatic trial) in patients with LN in Rio de Janeiro, Brazil, allocated in two groups: an intervention group (Dader Method for PC) and a control group (institution's usual care). Drug treatment adherence was measured by the combination of five questions normally used in clinical practice. RESULTS: A total of 131 patients were randomized, and 122 completed the study, with a mean follow-up of 12.7 months and use of six drugs per day and 10-12 doses per day. Low adherence was observed at baseline (intervention group: 30%; control group: 29%). PC showed 27% effectiveness (95% confidence interval (CI) -6% to 50%) in the intention to treat analysis and 31% (95% CI 0-52%) in per protocol analysis, considering all drugs. As for adherence to specific drugs for SLE, effectiveness of PC was 64% (95% CI 34-80%) with intention-to-treat analysis and 62% (95% CI 32-79%) in per protocol analysis. CONCLUSIONS: PC was effective for increasing drug treatment adherence in SLE. The detailed account provided by the Dader Method of the difficulties with patients' drug therapy proved invaluable to approach non-adherence.


Asunto(s)
Nefritis Lúpica/tratamiento farmacológico , Cumplimiento de la Medicación/estadística & datos numéricos , Servicios Farmacéuticos/organización & administración , Adulto , Brasil , Femenino , Estudios de Seguimiento , Humanos , Análisis de Intención de Tratar , Persona de Mediana Edad , Encuestas y Cuestionarios
8.
Int J Gynecol Cancer ; 29(1): 5-9, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30640676

RESUMEN

OBJECTIVES: The aim of this retrospective multicenter study was to investigate the extent, feasibility, and outcomes of minimally invasive surgery at the time of interval debulking surgery in different gynecological cancer centers. METHODS/MATERIALS: In December 2016, 20 gynecological cancer centers were contacted by e-mail, to participate in the INTERNATIONAL MISSION study. Seven centers confirmed and five were included, with a total of 127 patients diagnosed with advanced epithelial ovarian cancer after neoadjuvant chemotherapy and minimally invasive interval surgery. Only women with a minimum follow-up time of 6 months from interval surgery or any cancer-related event before 6 months were included in the survival analysis. Baseline characteristics, chemotherapy, and operative data were evaluated. Survival analysis was evaluated using the Kaplan-Meier method. RESULTS : All patients had optimal cytoreduction at the time of interval surgery: among them, 122 (96.1%) patients had no residual tumor. Median operative time was 225 min (range 60 - 600) and median estimated blood loss was 100 mL (range 70 - 1320). Median time to discharge was 2 days (1-33) and estimated median time to start chemotherapy was 20 days (range 15 - 60). Six (4.7%) patients experienced intraoperative complications, with one patient experiencing two serious complications (bowel and bladder injury at the same time). There were six (4.7%) patients with postoperative short-term complications: among them, three patients had severe complications. The conversion rate to laparotomy was 3.9 %. Median follow-up time was 37 months (range 7 - 86): 74 of 127 patients recurred (58.3%) and 31 (24.4%) patients died from disease. Median progression-free survival was 23 months and survival at 5 years was 52 % (95% CI: 35 to 67). CONCLUSIONS: Minimally invasive surgery may be considered for the management of patients with advanced ovarian cancer who have undergone neoadjuvant chemotherapy, when surgery is limited to low-complexity standard cytoreductive procedures.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Procedimientos Quirúrgicos de Citorreducción/mortalidad , Procedimientos Quirúrgicos Mínimamente Invasivos/mortalidad , Terapia Neoadyuvante/mortalidad , Neoplasia Residual/cirugía , Neoplasias Ováricas/cirugía , Adenocarcinoma de Células Claras/tratamiento farmacológico , Adenocarcinoma de Células Claras/patología , Adenocarcinoma de Células Claras/cirugía , Adenocarcinoma Mucinoso/tratamiento farmacológico , Adenocarcinoma Mucinoso/patología , Adenocarcinoma Mucinoso/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Terapia Combinada , Cistadenocarcinoma Seroso/tratamiento farmacológico , Cistadenocarcinoma Seroso/patología , Cistadenocarcinoma Seroso/cirugía , Neoplasias Endometriales/tratamiento farmacológico , Neoplasias Endometriales/patología , Neoplasias Endometriales/cirugía , Estudios de Factibilidad , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Neoplasia Residual/tratamiento farmacológico , Neoplasia Residual/patología , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/patología , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia
9.
Appetite ; 133: 252-261, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30458200

RESUMEN

Excessive salt intake has been associated with the development or worsening of chronic diseases such as hypertension and spontaneously hypertensive rats (SHR) have a typical increased sodium preference. Estrogens reduce sodium appetite, but we do not know whether such effect relates to alterations in sodium palatability. Here we evaluated the influence of ovarian hormones on orofacial motor responses, an index of palatability, to intra-oral infusion of 0.3 M NaCl (IONaCl). Adult female SHR and normotensive Holtzman rats (HTZ) were used. Sodium appetite was produced by water deprivation followed immediately by partial rehydration by drinking water to satiation (WD-PR protocol). Immediately at the end of WD-PR, animals received an IO-NaCl for videotape recording of orofacial motor responses. At the end of IO-NaCl, they had access to two bottles containing 0.3 M NaCl and water to ingest (sodium appetite test). Bilateral ovariectomy (OVX) enhanced 0.3 M NaCl intake during the sodium appetite test and increased the frequency of orofacial hedonic responses to IO-NaCl in both strains. It had no effect on aversive responses. Estradiol treatment in SHR-OVX decreased hedonic responses and increased aversive responses to IO-NaCl. It also reduced 0.3 M NaCl intake during the sodium appetite test, but had no effect on baseline mean arterial pressure and heart rate. The results suggest that ovarian hormones restrain WD-PR-induced sodium appetite by reducing the hedonic properties of sodium taste. The results also suggest that estrogens mediate such reduction, particularly in SHR.


Asunto(s)
Estradiol/farmacología , Cloruro de Sodio/administración & dosificación , Privación de Agua , Animales , Femenino , Ovariectomía , Distribución Aleatoria , Ratas Endogámicas SHR , Ratas Sprague-Dawley , Gusto/fisiología
10.
Photochem Photobiol Sci ; 17(4): 482-490, 2018 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-29582862

RESUMEN

Leishmaniasis is a neglected disease present in more than 88 countries. The currently adopted chemotherapy faces challenges related to side effects and the development of resistance. Photodynamic therapy (PDT) is emerging as a therapeutic modality for cutaneous leishmaniasis. Zn(ii) meso-tetrakis(N-ethylpyridinium-2-yl)porphyrin (ZnTE-2-PyP4+, ZnP) is a cationic, water-soluble, zinc porphyrin-based photosensitizer whose photodynamic effect on Leishmania braziliensis was analyzed by evaluating the number of visibly undamaged and motile cells, cell membrane integrity, mitochondrial membrane potential, and ultrastructural damage. Treatment of parasites with ZnP and light induced damage in up to 90% of L. braziliensis promastigote cells. Propidium iodide labeling suggested the loss of plasma membrane integrity. In samples treated with ZnP and light, a hyperpolarization of the mitochondrial membrane potential was also observed. Ultrastructural evaluation of promastigotes after photodynamic treatment indicated a loss of cytoplasmic material and the presence of vacuoles. Scanning electron microscopy showed wrinkling of the plasma membrane and a reduced cell volume. Additionally, the number of amastigotes per macrophage was reduced by about 40% after photodynamic application. The treatment showed no considerable toxicity against mammalian cells. Therefore, the results indicated that PDT associated with ZnTE-2-PyP4+ represents a promising alternative to cutaneous leishmaniasis treatment.


Asunto(s)
Antiparasitarios/farmacología , Leishmania braziliensis/efectos de los fármacos , Leishmania braziliensis/crecimiento & desarrollo , Leishmaniasis Cutánea/parasitología , Metaloporfirinas/farmacología , Fotoquimioterapia , Fármacos Fotosensibilizantes/farmacología , Antiparasitarios/química , Humanos , Leishmaniasis Cutánea/tratamiento farmacológico , Metaloporfirinas/química , Microscopía Electrónica de Rastreo , Pruebas de Sensibilidad Parasitaria , Fármacos Fotosensibilizantes/química
12.
Genet Mol Res ; 16(3)2017 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-28973774

RESUMEN

One hundred and eighty-two samples of unrelated people who requested the paternity test at the Molecular Biology and Genetics Laboratory of the Catholic University of Cuenca-Ecuador in the province of Azuay were studied, except for the D1S1656 (180 samples) and SE33 (89 samples) markers. The STRs D22S1045, D3S1358, VWA, D16S539, D2S1338, D8S1179, D21S11, D18S51, D19S433, TH01, FGA, D1S1656, D12S391, D10S1248, D2S441, and SE33 were typed from blood samples, amplifying the DNA by polymerase chain reactions and electrophoresis. The allele frequencies were estimated by simple counting and the impartial heterozygosity was also calculated. The Hardy-Weinberg equilibrium theory was studied. In the results obtained with the analyzed markers, the largest number of alleles can be observed in the markers with the highest polymorphic information content (PIC): D21S11, D16S539, D2S1338, D19S433, D18S51, FGA, D1S1656, and D12S391. In addition, SE33 was analyzed in certain samples, showing as result a high PIC, in fact, the highest one because of its great polymorphisc characteristic. Likewise, these markers are the ones providing the highest probability of discrimination and the lowest probability of coincidence.


Asunto(s)
Frecuencia de los Genes , Población/genética , Ecuador , Humanos , Repeticiones de Microsatélite , Polimorfismo Genético
13.
Med Oral Patol Oral Cir Bucal ; 22(1): e15-e23, 2017 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-27918734

RESUMEN

BACKGROUND AND OBJECTIVE: Considering the high possibility of dentist consult a patient with oral complications of chemotherapy and/or radiotherapy for oral cancer because of the advances in this area, this study aims to systematically review the literature to identify and suggest effective and safe protocols for the managements of oral complications in oncology patients. MATERIAL AND METHODS: The systematic review was designed by PICO and PRISMA including eligibility and exclusion criteria; the source of information and search strategy in PubMed according MeSH: "Mouth Neoplasms and Radiotherapy" and "Mouth Neoplasms and Drug Therapy" the period from 2010 to 2015; selection and data collection of study was carried form blind and independently by two researchers; risk of bias and methodological quality: ensured by the PEDro scale; synthesis of data: of oral complications were evaluated by adapted version of associative direction classification proposed by Costigan and collaborators; and data analysis was performed by the meta-analysis of BioEstat program (5.0) in the included studies. RESULTS: 2,700 articles found, 2,371 were selected after removal of duplicate and elected 40 full-text articles. Of these, only 06 articles were included in the systematic review with exclusion of others, per obtain punctuation ≥ 7 with high methodological quality for synthesis of the managements of oral complications. Since 05 articles were associated with low risk of bias composing the protocols suggestive for managements and the meta-analysis in odds ratio (0.916) to cure and relative risk (1.049) for the development of oral mucositis and pain. CONCLUSIONS: The protocols suggestive for managements of oral mucositis and pain with MuGard - mucoadhesive hydrogel; PerioAid Tratamiento® antiseptic mouthrinse with chlorhexidine and cetylpyridinium chloride; Episil® plus benzydamine - bioadhesive oromucosal gel; 0,03% of Triclosan mouthwash Colgate Plax; and Diode Laser Therapy of low-level are safe for oncology patients applied according to adopted clinical parameters.


Asunto(s)
Antineoplásicos/efectos adversos , Enfermedades de la Boca/etiología , Neoplasias de la Boca/tratamiento farmacológico , Neoplasias de la Boca/radioterapia , Traumatismos por Radiación/etiología , Protocolos Clínicos , Humanos , Radioterapia/efectos adversos
14.
J Evol Biol ; 29(11): 2205-2218, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27500505

RESUMEN

Each of the four serotypes of mosquito-borne dengue virus (DENV-1-4) comprises multiple, genetically distinct strains. Competitive displacement between strains within a serotype is a common feature of DENV epidemiology and can trigger outbreaks of dengue disease. We investigated the mechanisms underlying two sequential displacements by DENV-3 strains in Sri Lanka that each coincided with abrupt increases in dengue haemorrhagic fever (DHF) incidence. First, the post-DHF strain displaced the pre-DHF strain in the 1980s. We have previously shown that post-DHF is more infectious than pre-DHF for the major DENV vector, Aedes aegypti. Then, the ultra-DHF strain evolved in situ from post-DHF and displaced its ancestor in the 2000s. We predicted that ultra-DHF would be more infectious for Ae. aegypti than post-DHF but found that ultra-DHF infected a significantly lower percentage of mosquitoes than post-DHF. We therefore hypothesized that ultra-DHF had effected displacement by disseminating in Ae. aegypti more rapidly than post-DHF, but this was not borne out by a time course of mosquito infection. To elucidate the mechanisms that shape these virus-vector interactions, we tested the impact of RNA interference (RNAi), the principal mosquito defence against DENV, on replication of each of the three DENV strains. Replication of all strains was similar in mosquito cells with dysfunctional RNAi, but in cells with functional RNAi, replication of pre-DHF was significantly suppressed relative to the other two strains. Thus, differences in susceptibility to RNAi may account for the differences in mosquito infectivity between pre-DHF and post-DHF, but other mechanisms underlie the difference between post-DHF and ultra-DHF.


Asunto(s)
Virus del Dengue/patogenicidad , Dengue/epidemiología , Aedes , Animales , Virus del Dengue/genética , Interferencia de ARN , Sri Lanka , Virulencia
15.
Lupus ; 25(1): 75-80, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26385219

RESUMEN

Diffuse alveolar hemorrhage (DAH) is a rare but potentially catastrophic manifestation with a high mortality. Among rheumatologic diseases, it occurs most frequently in patients with systemic lupus erythematosus (SLE) and systemic vasculitis. Despite new diagnostic tools and therapies, it remains a diagnostic and therapeutic challenge. The aim of this work was to characterize the SLE patients with an episode of alveolar hemorrhage followed in our Clinical Immunology Unit (CIU). A retrospective chart review was carried out for all patients with SLE followed in CIU between 1984 and the end of 2013. We reviewed the following data: demographic characteristics, clinical and laboratory data, radiologic investigations, histologic studies, treatment, and outcome. We identified 10 episodes of DAH, corresponding to seven patients, all female. These represent 1.6% of SLE patients followed in our Unit. The age at DAH attack was 42.75 ± 18.9 years. The average time between diagnosis of SLE and the onset of DAH was 7.1 years. Three patients had the diagnosis of SLE and the DAH attack at the same time. Disease activity according to SLEDAI was high, ranging from 15 to 41. All patients were treated with methylprednisolone, 37.5% cyclophosphamide and 28.6% plasmapheresis. The overall mortality rate was 28.6%.


Asunto(s)
Hemorragia/etiología , Enfermedades Pulmonares/etiología , Lupus Eritematoso Sistémico/complicaciones , Alveolos Pulmonares , Adolescente , Adulto , Anciano , Femenino , Hemorragia/diagnóstico , Hemorragia/mortalidad , Humanos , Inmunosupresores/uso terapéutico , Enfermedades Pulmonares/diagnóstico , Enfermedades Pulmonares/mortalidad , Lupus Eritematoso Sistémico/diagnóstico , Lupus Eritematoso Sistémico/mortalidad , Lupus Eritematoso Sistémico/terapia , Registros Médicos , Persona de Mediana Edad , Plasmaféresis , Portugal , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
16.
J Chem Phys ; 144(12): 124306, 2016 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-27036447

RESUMEN

Conformational changes induced thermally or upon infrared excitation of matrix-isolated 6-methoxyindole were investigated. Narrowband near-infrared excitation of the first overtone of the N-H stretching vibration of each one of the two identified conformers is found to induce a selective large-scale conversion of the pumped conformer into the other one. This easily controllable bidirectional process consists in the intramolecular reorientation of the methoxy group and allowed a full assignment of the infrared spectra of the two conformers. Matrices with different conformational compositions prepared by narrow-band irradiations were subsequently used to investigate the effects of both thermal and broadband infrared excitations on the conformational mixtures. Particular attention is given to the influence of the matrix medium (Ar vs. Xe) and conformational effects of exposition of the sample to the spectrometer light source during the measurements.

17.
Asian-Australas J Anim Sci ; 29(1): 16-22, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26732323

RESUMEN

The intestinal environment plays a critical role in maintaining swine health. Many factors such as diet, microbiota, and host intestinal immune response influence the intestinal environment. Intestinal alkaline phosphatase (IAP) is an important apical brush border enzyme that is influenced by these factors. IAP dephosphorylates bacterial lipopolysaccharides (LPS), unmethylated cytosine-guanosine dinucleotides, and flagellin, reducing bacterial toxicity and consequently regulating toll-like receptors (TLRs) activation and inflammation. It also desphosphorylates extracellular nucleotides such as uridine diphosphate and adenosine triphosphate, consequently reducing inflammation, modulating, and preserving the homeostasis of the intestinal microbiota. The apical localization of IAP on the epithelial surface reveals its role on LPS (from luminal bacteria) detoxification. As the expression of IAP is reported to be downregulated in piglets at weaning, LPS from commensal and pathogenic gram-negative bacteria could increase inflammatory processes by TLR-4 activation, increasing diarrhea events during this phase. Although some studies had reported potential IAP roles to promote gut health, investigations about exogenous IAP effects or feed additives modulating IAP expression and activity yet are necessary. However, we discussed in this paper that the critical assessment reported can suggest that exogenous IAP or feed additives that could increase its expression could show beneficial effects to reduce diarrhea events during the post weaning phase. Therefore, the main goals of this review are to discuss IAP's role in intestinal inflammatory processes and present feed additives used as growth promoters that may modulate IAP expression and activity to promote gut health in piglets.

19.
Climacteric ; 18(4): 651-5, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25530207

RESUMEN

Estrogen replacement therapy is not thought to be a safe treatment for prevention of cardiovascular disease in menopausal women; isoflavones are a possible alternative. Estrogen produces beneficial effects on the cardiovascular system by enhancing production of nitric oxide, a vasoprotective and antiatherosclerotic agent. Estrogen-like compounds such as isoflavones are also suggested for increasing nitric oxide production. Isoflavones are present mainly in soy foods as glucosides, but soy isoflavone aglycones, the biologically active estrogen-like compounds, are absorbed faster and in higher amounts than their glucoside derivatives and show higher biological activity, implying that they may be more effective in preventing chronic diseases such as coronary heart disease. We evaluated an extract of soybeans fermented by Aspergillus awamori on which polyphenol glucosides were biotransformed to aglycone forms on production of nitric oxide, prostaglandin E2 and endothelin-1 in vitro in human endothelial cells, comparing it with a non-fermented extract. Bioconverted soybean extracts enhanced endothelin-1, nitric oxide and prostaglandin E2 production, while the unfermented extract only enhanced endothelin-1 production. Thus, only the aglycone-rich forms of soybean extracts were able to increase nitric oxide and prostaglandin E2 production, demonstrating that, in endothelial cells in vitro, they may be usable as therapeutic agents against the development of atherosclerosis.


Asunto(s)
Glycine max , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Isoflavonas/farmacología , Fitoestrógenos/farmacología , Extractos Vegetales/farmacología , beta-Glucanos/farmacología , Aspergillus/metabolismo , Biomarcadores/metabolismo , Biotransformación , Supervivencia Celular/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos
20.
J Chem Phys ; 140(6): 064306, 2014 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-24527914

RESUMEN

Monomers of (tetrazol-5-yl)-acetic acid (TAA) were obtained by sublimation of the crystalline compound and the resulting vapors were isolated in cryogenic nitrogen matrices at 13 K. The conformational and tautomeric composition of TAA in the matrix was characterized by infrared spectroscopy and vibrational calculations carried out at the B3LYP/6-311++G(d,p) level. TAA may adopt two tautomeric modifications, 1H- and 2H-, depending on the position of the annular hydrogen atom. Two-dimensional potential energy surfaces (PESs) of TAA were theoretically calculated at the MP2/6-311++G(d,p) level, for each tautomer. Four and six symmetry-unique minima were located on these PESs, for 1H- and 2H-TAA, respectively. The energetics of the detected minima was subsequently refined by calculations at the QCISD level. Two 1H- and three 2H-conformers fall within the 0-8 kJ mol(-1) energy range and should be appreciably populated at the sublimation temperature (∼330 K). Observation of only one conformer for each tautomer (1ccc and 2pcc) is explained in terms of calculated barriers to conformational rearrangements. All conformers with the cis O=COH moiety are separated by low barriers (less than 10 kJ mol(-1)) and collapse to the most stable 1ccc (1H-) and 2pcc (2H-) forms during deposition of the matrix. On the trans O=COH surfaces, the relative energies are very high (between 12 and 27 kJ mol(-1)). The trans forms are not thermally populated at the sublimation conditions and were not detected in matrices. One high-energy form in each tautomer, 1cct (1H-) and 2pct (2H-), was found to differ from the most stable form only by rotation of the OH group and separated from other forms by high barriers. This opened a perspective for their stabilization in a matrix. 1cct and 2pct were generated in the matrices selectively by means of narrow-band near-infrared (NIR) irradiations of the samples at 6920 and 6937 cm(-1), where the first OH stretching overtone vibrations of 1ccc and 2pcc occur. The reverse transformations could be induced by irradiations at 7010 and 7030 cm(-1), transforming 1cct and 2pct back to 1ccc and 2pcc, also selectively. Besides the NIR-induced transformations, the photogenerated 1cct and 2pct forms also decay in N2 matrices back to 1ccc and 2pcc spontaneously, with characteristic decay times of hours (1H) and tens of minutes (2H). The decay mechanism is rationalized in terms of the proton tunneling. In crystals, TAA exists exclusively as 1H-tautomer. By contrast, the tautomeric composition of the matrix-isolated monomers was found to consist of both 1H- and 2H-tautomers, in comparable amounts. A mechanistic discussion of the tautomerization process occurring during sublimation, accounting also for the observed minor decomposition of TAA leading to CO2 and 5-methyl-tetrazole, is proposed.


Asunto(s)
Ácido Acético/química , Tetrazoles/química , Isomerismo , Modelos Moleculares , Conformación Molecular
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