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1.
Microorganisms ; 11(6)2023 May 31.
Article in English | MEDLINE | ID: mdl-37374972

ABSTRACT

Streptomyces coelicolor M145 is a model strain extensively studied to elucidate the regulation of antibiotic biosynthesis in Streptomyces species. This strain abundantly produces the blue polyketide antibiotic, actinorhodin (ACT), and has a low lipid content. In a process designed to delete the gene encoding the isocitrate lyase (sco0982) of the glyoxylate cycle, an unexpected variant of S. coelicolor was obtained besides bona fide sco0982 deletion mutants. This variant produces 7- to 15-fold less ACT and has a 3-fold higher triacylglycerol and phosphatidylethanolamine content than the original strain. The genome of this variant was sequenced and revealed that 704 genes were deleted (9% of total number of genes) through deletions of various sizes accompanied by the massive loss of mobile genetic elements. Some deletions include genes whose absence could be related to the high total lipid content of this variant such as those encoding enzymes of the TCA and glyoxylate cycles, enzymes involved in nitrogen assimilation as well as enzymes belonging to some polyketide and possibly trehalose biosynthetic pathways. The characteristics of this deleted variant of S. coelicolor are consistent with the existence of the previously reported negative correlation existing between lipid content and antibiotic production in Streptomyces species.

2.
J Control Release ; 360: 293-303, 2023 08.
Article in English | MEDLINE | ID: mdl-37391032

ABSTRACT

In an attempt to tune drug release and subsequent pharmacokinetics once administered intravenously, we have synthesized three lipid-drug conjugates (LDCs) of dexamethasone (DXM) each possessing a different lipid-drug chemical linkage: namely ester, carbamate and carbonate. These LDCs were thoroughly characterized before being turned into nanoscale particles by an emulsion-evaporation process using DSPE-PEG2000 (Distearoyl-sn-Glycero-3-Phosphoethanolamine-N-(methoxy(polyethylene glycol)-2000) as the only excipient. Spherical nanoparticles (NPs) of about 140-170 nm, with a negative zeta potential, were obtained for each LDC and exhibited good stability upon storage at 4 °C for 45 days with no recrystallization of LDCs observed. LDC encapsulation efficacy was above 95% for the three LDCs, leading to a LDC loading of about 90% and an equivalent DXM loading above 50%. Although the ester and carbonate NPs did not exhibit any toxicity up to an equivalent DXM concentration of 100 µg/mL, the carbamate LDC NPs appeared very toxic towards RAW 264.7 macrophages and were discarded. Both ester and carbonate LDC NPs were shown to exert anti-inflammatory activity on LPS-activated macrophages. DXM release from LDC NPs in murine plasma was faster from ester than from carbonate NPs. Finally, pharmacokinetics and biodistribution were conducted, showing a lower exposure to DXM from carbonate LDC NPs than from ester LDC NPs, correlated with the slower DXM release from carbonate LDC NPs. These results outline the need for extended studies to find the best prodrug system for extended drug release.


Subject(s)
Nanoparticles , Prodrugs , Mice , Animals , Tissue Distribution , Anti-Inflammatory Agents , Nanoparticles/chemistry , Dexamethasone
3.
Biomolecules ; 12(8)2022 07 25.
Article in English | MEDLINE | ID: mdl-35892336

ABSTRACT

Yarrowia lipolytica is a promising oleaginous yeast for producing unusual lipids, such as odd-chain fatty acids (OCFA). Their diverse applications and low natural production make OCFA particularly interesting. In recent studies, inhibiting the catabolic pathway of precursor, boosting precursor pools, and optimizing substrate combination greatly improved the production of OCFA in Y. lipolytica. We explored the lipid readjustment of OCFA in engineered Y. lipolytica strains. NPLC-Corona-CAD® evidenced a time-dependent overproduction of free fatty acids, diglycerides, and phosphatidylcholine (PC) in obese LP compared to obese L. Phosphatidylethanolamine (PE) and phosphatidylinositol, largely overproduced in obese LP at 72 h compared to obese L, vanished at 216 h. The fatty acyls (FAs) composition of glycero- and glycerophospholipids was determined by NPLC-APPI+-HRMS from in-source generated monoacylglycerol-like fragment ions. C18:1 and C17:1 were predominant acylglycerols in obese L and obese LP, respectively. Phosphatidic acid, PE, and PC exhibited similar FAs composition but differed in their molecular species distributions. Cardiolipin (CL) is known to contain mostly C18:2 FAs corresponding to the composition in obese L, 50% of C18:2, and 35% of C18:1. In obese LP, both FAs dropped to drop to 20%, and C17:1 were predominant, reaching 55%. We hypothesize that CL-modified composition in obese LPs may alter mitochondrial function and limit lipid production.


Subject(s)
Yarrowia , Fatty Acids/metabolism , Obesity , Yarrowia/metabolism
4.
J Chromatogr A ; 1673: 463093, 2022 Jun 21.
Article in English | MEDLINE | ID: mdl-35569175

ABSTRACT

We recently published a new concept using monoacylglycerol-like fragments [MG+H-H2O]+ (ions B) produced in-source by atmospheric pressure photoionization in positive mode and high-resolution mass spectrometry for the determination of the fatty acyl (FA) composition of triacylglycerols (TGs) from plant oils. This study extends the concept to the phospholipids (PLs) category and shows that the APCI+ source can also be used. Moreover, the coupling with NP-LC allows to simultaneously analyze different PLs classes in the same sample. We compared the relative intensities of the ions B produced in-source to the % composition of FAs determined by GC-FID. In the case of PLs from natural extracts composed exclusively of diacyl-PLs, the relative intensities of ions B are close to the % of the FAs obtained by GC-FID. This approach is not directly useable for extracts containing plasmalogens (P-PLs). For these PLs, acidic hydrolysis by HCl fumes allows hydrolyzing selectively vinyl ether functions to form lyso-PLs. The analysis of hydrolyzed extracts makes it possible to obtain the composition of P-PLs FAs thanks to the lyso-PLs thus formed, while the diacyl-PLs composition remains unchanged. Unlike GC-FID FAs determination, this approach allows a distinction between the diacyl-PLs and P-PLs FAs composition. We also found that the ion B intensities were consistent among the PL classes (PG, PE, PA, PI, CL, PS and PC) and lyso- forms (LPE and LPC). In the case of the diacyl-PLs extracts analyzed, no statistically significant differences were found between the PLs FAs compositions calculated from ion B intensities and the corresponding GC-FID data. A weighting coefficient was applied to correct ion B intensities issued from polyunsaturated FAs with three or more double bonds. The fatty alkenyls composition of P-PLs could also be calculated from the % intensities of specific ions.


Subject(s)
Atmospheric Pressure , Phospholipids , Plasmalogens , Gas Chromatography-Mass Spectrometry , Mass Spectrometry/methods , Monoglycerides
5.
Eur J Pharm Biopharm ; 170: 112-120, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34890789

ABSTRACT

In a strategy to improve macrophage targeting of glucocorticoids (GCs) for anti-inflammatory therapy, a so-called nanoprodrug of budesonide palmitate decorated by mannose moieties was designed. The synthesis of budesonide palmitate (BP) was obtained by esterification and mannosylated lipid (DSPE-PEG-Man) by reacting 1,2-Distearoyl-sn-Glycero-3-Phosphoethanolamine (DSPE)-polyethylene glycol-amine and α-D-mannopyranosylphenyl isothiocyanate (MPITC). Nanoparticles were formulated by emulsion-evaporation and different ratios of mannosylated lipid were introduced in the formulation of BP nanoprodrugs. Using up to 75% of DSPE-PEG-man (75/25) led to 200 nm particles with a polydispersity index below 0.2, a negative zeta potential ranging from -10 to -30 mV, and one-month stability at 4 °C. The encapsulation efficiency of BP approached 100% proving that the prodrug was associated with the particles, leading to a final BP loading of 50-to 60% (w/w). The lectin agglutination test confirmed the availability of mannose on the nanoprodrug surface. Nanoprodrug uptake by RAW 264.7 macrophages was observed by confocal microscopy and flow cytometry. After 24 and 48 h of incubation, a significantly greater internalization of mannosylated nanoparticles as compared to PEGylated nanoparticles was achieved. The mannose receptor-mediated uptake was confirmed by a mannan inhibition study. After LPS-induced inflammation, the anti-inflammatory effect of mannosylated nanoparticles was assessed. After 48 h of incubation, cytokines (MCP-1 and TNFα) were reduced demonstrating that the functionalization of nanoprodrugs is possible and efficient.


Subject(s)
Budesonide/pharmacology , Mannose/pharmacology , Prodrugs/chemical synthesis , Animals , Biological Availability , Budesonide/administration & dosage , Cell Survival , Cells, Cultured , Cytokines/metabolism , Drug Compounding , Drug Delivery Systems , Drug Liberation , Drug Stability , Macrophages/drug effects , Mannose/administration & dosage , Mice , Nanoparticles , Tissue Distribution
6.
Anal Chim Acta ; 1178: 338809, 2021 Sep 15.
Article in English | MEDLINE | ID: mdl-34482865

ABSTRACT

We present a new analytical approach for the analysis of triacylglycerol fatty acyls distribution by normal phase liquid chromatography (NPLC) coupled with APPI+-HRMS. The NPLC method used allows the separation of more than 30 classes of lipids. The energy of the APPI+ source enables the formation of low-intensity ions B fragments ([RC = O+74]+ <3%), characteristic of lipids with a glycerol esterified by one or more fatty acyls. We found the relative intensities of ions B were close to the fatty acyl distribution. To establish the proof of concept, we decided to focus on the triacylglycerols (TGs) class, the major component of plant oils. By either NPLC or FIA, the TGs class appeared as a single peak. In our experimental conditions, ions B are always present in the mass spectra of TGs and each ion B is specific to a fatty acyl group. The Orbitrap mass spectrometer featured high enough resolution and accuracy to identify ions B and distinguish them from other TG fragment ions. A further adjustment of the fatty acyls relative quantities calculation from ions B intensities was computed using weighting coefficients of ions B response. The methodology was developed and validated using plant oils characterized by a GC-FID reference method. NPLC-APPI+-HRMS method offers the advantage of analyzing the fatty acyl composition of complex lipid extracts without the need for sample preparation.


Subject(s)
Atmospheric Pressure , Monoglycerides , Chromatography, High Pressure Liquid , Lipids , Mass Spectrometry , Triglycerides
7.
Front Microbiol ; 12: 623919, 2021.
Article in English | MEDLINE | ID: mdl-33692768

ABSTRACT

In this issue we demonstrated that the phospholipid content of Streptomyces lividans varies greatly with Pi availability being was much lower in Pi limitation than in Pi proficiency whereas that of Streptomyces coelicolor varied little with Pi availability. In contrast the content in phosphate free ornithine lipids was enhanced in both strains in condition of phosphate limitation. Ornithine lipids biosynthesis starts with the N-acylation of ornithine to form lyso-ornithine that is then O-acylated to yield ornithine lipid. The operon sco1222-23 was proposed to be involved in the conversion of specific amino acids into ornithine in condition of phosphate limitation whereas the sco0921-20 operon encoding N- and O-acyltransferase, respectively, was shown to be involved in the biosynthesis of these lipids. The expression of these two operons was shown to be under the positive control of the two components system PhoR/PhoP and thus induced in phosphate limitation. The expression of phoR/phoP being weak in S. coelicolor, the poor expression of these operons resulted into a fivefold lower ornithine lipids content in this strain compared to S. lividans. In the deletion mutant of the sco0921-20 operon of S. lividans, lyso-ornithine and ornithine lipids were barely detectable and TAG content was enhanced. The complementation of this mutant by the sco0921-20 operon or by sco0920 alone restored ornithine lipids and TAG content to wild type level and was correlated with a twofold increase in the cardiolipin content. This suggested that SCO0920 bears, besides its broad O-acyltransferase activity, an N-acyltransferase activity and this was confirmed by the detection of lyso-ornithine in this strain. In contrast, the complementation of the mutant by sco0921 alone had no impact on ornithine lipids, TAG nor cardiolipin content but was correlated with a high lyso-ornithine content. This confirmed that SCO0921 is a strict N-acyltransferase. However, interestingly, the over-expression of the sco0921-20 operon or of sco0921 alone in S. coelicolor, led to an almost total disappearance of phosphatidylinositol that was correlated with an enhanced DAG and TAG content. This suggested that SCO0921 also acts as a phospholipase C, degrading phosphatidylinositol to indirectly supply of phosphate in condition of phosphate limitation.

8.
Pharmaceutics ; 13(1)2021 Jan 12.
Article in English | MEDLINE | ID: mdl-33445646

ABSTRACT

Cyclosporin A (CsA) is a molecule with well-known immunosuppressive properties. As it also acts on the opening of mitochondrial permeability transition pore (mPTP), CsA has been evaluated for ischemic heart diseases (IHD). However, its distribution throughout the body and its physicochemical characteristics strongly limit the use of CsA for intravenous administration. In this context, nanoparticles (NPs) have emerged as an opportunity to circumvent the above-mentioned limitations. We have developed in our laboratory an innovative nanoformulation based on the covalent bond between squalene (Sq) and cyclosporin A to avoid burst release phenomena and increase drug loading. After a thorough characterization of the bioconjugate, we proceeded with a nanoprecipitation in aqueous medium in order to obtain SqCsA NPs of well-defined size. The SqCsA NPs were further characterized using dynamic light scattering (DLS), cryogenic transmission electron microscopy (cryoTEM), and high-performance liquid chromatography (HPLC), and their cytotoxicity was evaluated. As the goal is to employ them for IHD, we evaluated the cardioprotective capacity on two cardiac cell lines. A strong cardioprotective effect was observed on cardiomyoblasts subjected to experimental hypoxia/reoxygenation. Further research is needed in order to understand the mechanisms of action of SqCsA NPs in cells. This new formulation of CsA could pave the way for possible medical application.

9.
Front Microbiol ; 11: 1399, 2020.
Article in English | MEDLINE | ID: mdl-32655536

ABSTRACT

In condition of over-expression, SCO3201, a regulator of the TetR family was previously shown to strongly inhibit antibiotic production and morphological differentiation in Streptomyces coelicolor M145. In order to elucidate the molecular processes underlying this interesting, but poorly understood phenomenon, a comparative analysis of the lipidomes and transcriptomes of the strain over-expressing sco3201 and of the control strain containing the empty plasmid, was carried out. This study revealed that the strain over-expressing sco3201 had a higher triacylglycerol content and a lower phospholipids content than the control strain. This was correlated with up- and down- regulation of some genes involved in fatty acids biosynthesis (fab) and degradation (fad) respectively, indicating a direct or indirect control of the expression of these genes by SCO3201. In some instances, indirect control might involve TetR regulators, whose encoding genes present in close vicinity of genes involved in lipid metabolism, were shown to be differentially expressed in the two strains. Direct interaction of purified His6-SCO3201 with the promoter regions of four of such TetR regulators encoding genes (sco0116, sco0430, sco4167, and sco6792) was demonstrated. Furthermore, fasR (sco2386), encoding the activator of the main fatty acid biosynthetic operon, sco2386-sco2390, has been shown to be an illegitimate positive regulatory target of SCO3201. Altogether our data demonstrated that the sco3201 over-expressing strain accumulates TAG and suggested that degradation of fatty acids was reduced in this strain. This is expected to result into a reduced acetyl-CoA availability that would impair antibiotic biosynthesis either directly or indirectly.

10.
Antibiotics (Basel) ; 9(6)2020 May 26.
Article in English | MEDLINE | ID: mdl-32466356

ABSTRACT

Streptomycetes are well known antibiotic producers and are among the rare prokaryotes able to store carbon as lipids. Previous comparative studies of the weak antibiotic producer Streptomyces lividans with its ppk mutant and with Streptomyces coelicolor, which both produce antibiotics, suggested the existence of a negative correlation between total lipid content and the ability to produce antibiotics. To determine whether such a negative correlation can be generalized to other Streptomyces species, fifty-four strains were picked randomly and grown on modified R2YE medium, limited in phosphate, with glucose or glycerol as the main carbon source. The total lipid content and antibiotic activity against Micrococcus luteus were assessed for each strain. This study revealed that the ability to accumulate lipids was not evenly distributed among strains and that glycerol was more lipogenic than glucose and had a negative impact on antibiotic biosynthesis. Furthermore, a statistically significant negative Pearson correlation between lipid content and antibiotic activity could be established for most strains, but a few strains escape this general law. These exceptions are likely due to limits and biases linked to the type of test used to determine antibiotic activity, which relies exclusively on Micrococcus luteus sensitivity. They are characterized either by high lipid content and high antibiotic activity or by low lipid content and undetectable antibiotic activity against Micrococcus luteus. Lastly, the comparative genomic analysis of two strains with contrasting lipid content, and both named Streptomyces antibioticus (DSM 41,481 and DSM 40,868, which we found to be phylogenetically related to Streptomyces lavenduligriseus), indicated that some genetic differences in various pathways related to the generation/consumption of acetylCoA could be responsible for such a difference.

11.
Mol Pharm ; 16(9): 4045-4058, 2019 09 03.
Article in English | MEDLINE | ID: mdl-31361499

ABSTRACT

Retinoblastoma is a malignant tumor of the retina in infants. Conventional therapies are associated to severe side effects and some of them induce secondary tumors. Photodynamic therapy (PDT) thus appears as a promising alternative as it is nonmutagenic and generates minimal side effects. The effectiveness of PDT requires the accumulation of a photosensitizer (PS) in the tumor. However, most porphyrins are hydrophobic and aggregate in aqueous medium. Their incorporation into a nanocarrier may improve their delivery to the cell cytoplasm. In this work, we designed biodegradable liponanoparticles (LNPs) consisting of a poly(d,l)-lactide (PDLLA) nanoparticle coated with a phospholipid (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine/1,2-dioleoyl-3-trimethylammonium-propane) bilayer. An anticancer drug, beta-lapachone (ß-Lap) and a PS, m-THPC, were co-encapsulated for combined chemo- and PDT because it has been suggested that they may have a synergistic effect based on the activation of ß-Lap by PDT-induced over-expression of the enzyme NQO1. Using dynamic light scattering measurements, cryogenic transmission electron microscopy, and fluorescence confocal microscopy, we selected the appropriate conditions for the encapsulation of the compounds. LNPs were internalized in retinoblastoma cells within few hours. No obvious synergistic effect related to the activation of ß-Lap by PDT was observed. Conversely, the LNPs were cytotoxic at lower doses of the two encapsulated compounds as compared to the single therapies. Analysis of the combinatorial treatment showed that PDT and chemotherapy had an additive effect on the viability of retinoblastoma cells.


Subject(s)
Fatty Acids, Monounsaturated/chemistry , Mesoporphyrins/chemistry , Nanoparticles/chemistry , Naphthoquinones/chemistry , Phosphatidylcholines/chemistry , Photochemotherapy/methods , Polyesters/chemistry , Quaternary Ammonium Compounds/chemistry , Retinoblastoma/drug therapy , Cell Line, Tumor , Cell Survival/drug effects , Cryoelectron Microscopy , Drug Compounding/methods , Drug Delivery Systems/methods , Drug Stability , Dynamic Light Scattering , Humans , Microscopy, Confocal , Photosensitizing Agents/chemistry , Retinoblastoma/pathology
12.
Mol Pharm ; 16(7): 2999-3010, 2019 07 01.
Article in English | MEDLINE | ID: mdl-31117740

ABSTRACT

The encapsulation of glucocorticoids, such as dexamethasone, in nanoparticles (NPs) faces two main issues: a low drug loading and the destabilization of the nanoparticle suspension due to drug crystallization. Here, we successfully formulated a prodrug of dexamethasone, dexamethasone palmitate (DXP), into nanoparticles stabilized by the sole presence of distearoyl- sn-glycero-3-phosphoethanolamine- N-[methoxy(poly(ethylene glycol))-2000] (DSPE-PEG2000). Two formulation processes, nanoprecipitation and emulsion-evaporation, allowed the formation of stable nanoparticles. By adjusting the drug/lipid ratio and the DXP concentration, nanoparticles of DXP (DXP-NPs) with a size between 130 and 300 nm can be obtained. Owing to the presence of DSPE-PEG2000, a high drug entrapment efficiency of 98% w/w was reached for both processes, corresponding to a very high equivalent dexamethasone drug loading of around 50% w/w in the absence of crystallization upon storage at 4 °C. The anti-inflammatory activity of DXP-NPs was preserved when incubated with macrophages activated with lipopolysaccharide. Pharmacokinetics parameters were evaluated after intravenous (IV) injection of DXP-NPs to healthy mice. The release of DXM from DXP-NPs in plasma was clearly controlled up to 18 h compared with the free drug, which was rapidly eliminated from plasma after administration. In conclusion, a novel type of nanoparticle combining the advantages of prodrugs and nanoparticles was designed, easy to produce with a high loading efficiency and leading to modified pharmacokinetics and tissue distribution after IV administration.


Subject(s)
Anti-Inflammatory Agents/pharmacokinetics , Dexamethasone/pharmacokinetics , Drug Compounding/methods , Drug Delivery Systems/methods , Nanoparticles/chemistry , Prodrugs/pharmacokinetics , Animals , Anti-Inflammatory Agents/chemistry , Cell Survival/drug effects , Crystallization , Dexamethasone/administration & dosage , Dexamethasone/chemistry , Drug Liberation , Drug Stability , Injections, Intravenous , Male , Mice , Mice, Inbred DBA , Nanoparticles/administration & dosage , Particle Size , Phosphatidylethanolamines/administration & dosage , Phosphatidylethanolamines/chemistry , Polyethylene Glycols/administration & dosage , Polyethylene Glycols/chemistry , Prodrugs/administration & dosage , Prodrugs/chemistry , RAW 264.7 Cells , Tissue Distribution
13.
J Control Release ; 296: 179-189, 2019 02 28.
Article in English | MEDLINE | ID: mdl-30659904

ABSTRACT

Rheumatoid arthritis (RA) is a prevalent autoimmune disease characterized by joint inflammation, bone and cartilage erosion. The use of glucocorticoids in the treatment of RA is hampered by significant side effects induced by their unfavorable pharmacokinetics. Delivering glucocorticoids by means of nanotechnologies is promising but the encapsulation of highly crystalline and poorly water-soluble drugs results in poor loading and low stability. We report here the design of 130 nm nanoparticles made of solely dexamethasone palmitate, stabilized by polyethylene glycol-linked phospholipids displaying a negative zeta potential (-55 mV), high entrapment efficiency and stability over 21 days under storage at 4 °C. X ray diffraction showed no crystallization of the drug. When incubated in serum, nanoparticles released free dexamethasone which explains the in vitro anti-inflammatory effect on LPS-activated RAW 264.7 macrophages. Moreover, we demonstrate in a murine collagen-induced arthritis model the improved therapeutic efficacy of these nanoparticles. Their passive accumulation in arthritic joints leads to disease remission and recovery of the joint structure at a dose of 1 mg/kg dexamethasone, without any adverse effects. Dexamethasone palmitate nanoparticles are promising in the treatment of inflammation in rheumatoid arthritis with a very significant difference occurring at the late stage of inflammation allowing to prevent the progression of the disease.


Subject(s)
Anti-Inflammatory Agents/administration & dosage , Arthritis, Experimental/drug therapy , Arthritis, Rheumatoid/drug therapy , Dexamethasone/administration & dosage , Drug Carriers/administration & dosage , Nanoparticles/administration & dosage , Palmitates/administration & dosage , Animals , Arthritis, Experimental/pathology , Arthritis, Rheumatoid/pathology , Joints/drug effects , Joints/pathology , Male , Mice , Mice, Inbred DBA , RAW 264.7 Cells
14.
Med. interna (Caracas) ; 34(2): 128-132, 2018. ilus, tab
Article in Spanish | LILACS, LIVECS | ID: biblio-1007866

ABSTRACT

Existe una asociación epidemiológica entre sífilis e infección por VIH; las úlceras genitales favorecen la transmisión de Treponema pallidum y éste a su vez, la transmisión del VIH. La dermatitis seborreica (DS) se presenta en 2 a 4% de la población general; sin embargo, en los pacientes con infección por VIH/SIDA y SIFILIS es significativamente mayor, llegando a 85% en algunas series. Se presenta el caso de un paciente masculino de 22 años de edad, natural y procedente del Distrito Capital, Venezuela, sin otras patologías conocidas, quien acude a la emergencia por presentar periodos de hetero agresividad y desorientación témporo ­ espacial., El familiar refiere aparición de lesiones descamativas de fondo eritematoso en región facial desde hace 6 meses, no pruriginosas y a la exploración física se evidencia parafasia y pupila de Argyll- Robertson. Se reportan serologías Positivas para HIV por ELISA de 4ta Generación, VDRL Reactivo a 4 diluciones y FTA-ABS Reactivo, La punción Lumbar evidenció pleocitosis, hiperproteinorraquia, hipoglucorraquia y VDRL REACTIVO. La biopsia cutánea con coloración argéntica de Fontana fué positiva para Treponema pallidum, con mejoría clínica significativa posterior al cumplimiento del esquema de Penicilina Cristalina. La dermatitis seborreica puede ser uno de los primeros indicadores de infección por VIH, por lo cual en toda dermatitis seborreica atípica, extensa o que no responda a tratamiento debe solicitarse serología para VIH y VDRL(AU)


There is an epidemiological association between syphilis and HIV infection; genital ulcers facilitatethe transmission of Treponema pallidum and this in turn, the transmission of HIV. Seborrheic dermatitis (SD) occurs in 2 to 4% of the general population; however, in patients with HIV / AIDS and SIFILIS infection it is significantly higher, reaching 85% in some series. We present the case of a male patient, of a 22 years-old , natural from the Caracas, Venezuela, without other known pathologies, who came to the emergency ward due to periods of aggressiveness and temporo - spatial disorientation. Desquamative lesions with an erythematous background in in his face appeared 6 months earlier.The neurological examination showeds paraphasia and Argyll-Robertson´ pupil. Positive serologies for HIV by 4th Generation ELISA and VDRL reactive at 4 dilutions as well as positive FTA-ABS were reported, Lumbar tab evidenced pleocytosis, hyperproteinorrachia, hypoglucorraquia and reagent VDRL . The skin biopsy with Fontana silver coloration was positive for Treponema pallidum and he improved clinically after treatment with a Crystalline Penicillin scheme. Seborrheic dermatitis may be one of the first indicators of HIV infection, so in all atypical seborrheic dermatitis, extensive or unresponsive to treatment, serology for HIV and VDRL should be determined(AU)


Subject(s)
Humans , Male , Adult , Treponema pallidum , Syphilis/physiopathology , HIV/drug effects , Dermatitis, Seborrheic/physiopathology , Epidemiology , Internal Medicine
15.
J Chromatogr A ; 1514: 54-71, 2017 Sep 08.
Article in English | MEDLINE | ID: mdl-28774713

ABSTRACT

One important challenge in lipid class analysis is to develop a method suitable or, at least adaptable, for a vast diversity of samples. In the current study, an improved normal-phase liquid chromatography (NPLC) method allowed analyzing the lipid classes present in mammalian, vegetable as well as microorganism (yeast and bacteria) lipid samples. The method effectively separated 30 lipid classes or subclasses with a special focus on medium polarity lipids. The separation was carried out with bare silica stationary phase and was coupled to evaporative light scattering detection (ELSD), charged aerosol detection (Corona-CAD®) and mass spectrometry. Solutions are provided to circumvent technical issues (such as pumping solvents of low viscosity, solvent purity, rinsing step). The influence of mobile phase composition and addition of ionic modifiers on the chromatographic behavior of particular lipid classes is documented. A comparison between ELSD and Corona-CAD® confirmed the interest of this later detector for samples with a wide range of concentration of different lipids. Three common atmospheric pressure ionization interfaces were used for coupling the NPLC separation to a LTQ Velos Pro® mass spectrometer. The comparison of the chromatographic profiles showed that atmospheric pressure chemical ionization (APCI) and atmospheric pressure photoionization (APPI) are both suitable to detect the different lipid classes whereas APPI allows a better sensitivity for lipids at low-concentration.


Subject(s)
Chromatography, High Pressure Liquid/methods , Lipids/analysis , Spectrometry, Mass, Electrospray Ionization , Aerosols/chemistry , Animals , Atmospheric Pressure , Brain/metabolism , Cattle , Chickens , Egg Yolk/chemistry , Egg Yolk/metabolism , Escherichia coli/chemistry , Escherichia coli/metabolism , Ions/chemistry , Lipids/chemistry , Liver/chemistry , Liver/metabolism , Myocardium/chemistry , Myocardium/metabolism , Saccharomyces cerevisiae/chemistry , Saccharomyces cerevisiae/metabolism , Solvents/chemistry , Glycine max/chemistry , Glycine max/metabolism
16.
J Cell Biochem ; 118(10): 3480-3487, 2017 10.
Article in English | MEDLINE | ID: mdl-28345768

ABSTRACT

Transplant vasculopathy may be considered as an accelerated form of atherosclerosis resulting in chronic rejection of vascularized allografts. After organ transplantation, a diffuse intimal thickening is observed, leading to the development of an atherosclerosis plaque due to a significant monocyte infiltration. This results from a chronic inflammatory process induced by the immune response. In this study, we investigated the impact of two immunosuppressive drugs used in therapy initiated after organ transplantation, mycophenolate mofetil, and rapamycin, on the apoptotic response of monocytes induced or not by oxidized LDL. Here we show the pro-apoptotic effect of these two drugs through two distinct signaling pathways and we highlight a synergistic effect of rapamycin on apoptosis induced by oxidized LDL. In conclusion, since immunosuppressive therapy using mycophenolate mofetil or rapamycin can increase the cell death in a monocyte cell line, this treatment could exert similar effects on human monocytes in transplant patients, and thus, prevent transplant vasculopathy, atherosclerosis development, and chronic allograft rejection. J. Cell. Biochem. 118: 3480-3487, 2017. © 2017 Wiley Periodicals, Inc.


Subject(s)
Apoptosis/drug effects , Monocytes/metabolism , Mycophenolic Acid/pharmacology , Signal Transduction/drug effects , Sirolimus/pharmacology , Humans , Lipoproteins, LDL/pharmacology , U937 Cells
17.
J Chromatogr A ; 1464: 55-63, 2016 Sep 16.
Article in English | MEDLINE | ID: mdl-27554026

ABSTRACT

An evaluation of solvents alternative to n-heptane (d-limonene and hexamethyldisiloxane) and chloroform (cyclopentyl methyl ether, 2-methyltetrahydrofuran and isopentyl acetate) was developed for lipid classes separation of non-polar cholesteryl ester to highly polar phospholipids by high-performance liquid chromatography on bare silica stationary phase and evaporative light-scattering detection. Screening of alternative solvents was used to estimate their compatibility with liquid chromatography and evaporative light-scattering detection and to evaluate their chromatographic selectivity. This work shows that n-heptane can be advantageously replaced by hexamethyldisiloxane. An increase of non-polar lipids retention is observed with hexamethyldisiloxane as weak solvent. Chloroform, which is largely used for lipid analysis, might be replaced efficaciously by cyclopentyl methyl ether, 2-methyltetrahydrofuran or isopentyl acetate. Aside from offering a different selectivity, the gradients composed by one or both alternative solvents gave efficient and comparable or even better separations than those obtained with conventional solvents.


Subject(s)
Lipids/chemistry , Chromatography, High Pressure Liquid/instrumentation , Chromatography, High Pressure Liquid/methods , Molecular Structure
18.
Rev. Esc. Enferm. USP ; 48(6): 1111-1118, 12/2014. tab, graf
Article in English | LILACS, BDENF - Nursing | ID: lil-736327

ABSTRACT

Objective To analyze the production of scientific knowledge about the use of patients’ classification instruments in care and management practice in Brazil. Method Integrative literature review with databases search in: Latin American and Caribbean Literature on Health Sciences (LILACS), Medical Literature Analysis and Retrieval System on-line (MEDLINE), Cumulative Index to Nursing and Allied Health Literature (CINAHL) and SCOPUS, between January 2002 through December 2013. Results 1,194 studies were found, 31 met the inclusion criteria. We observed a higher number of studies in the category care plans and workload (n=15), followed by the category evaluation of psychometric properties (n=14). Conclusion Brazilian knowledge production has not yet investigated some purposes of using instruments for classifying patients in professional nursing practice. The identification of unexplored areas can guide future research on the topic.
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Objective To analyze the production of scientific knowledge about the use of patients’ classification instruments in care and management practice in Brazil. Method Integrative literature review with databases search in: Latin American and Caribbean Literature on Health Sciences (LILACS), Medical Literature Analysis and Retrieval System on-line (MEDLINE), Cumulative Index to Nursing and Allied Health Literature (CINAHL) and SCOPUS, between January 2002 through December 2013. Results 1,194 studies were found, 31 met the inclusion criteria. We observed a higher number of studies in the category care plans and workload (n=15), followed by the category evaluation of psychometric properties (n=14). Conclusion Brazilian knowledge production has not yet investigated some purposes of using instruments for classifying patients in professional nursing practice. The identification of unexplored areas can guide future research on the topic.

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Objetivo Analizar la producción del conocimiento científico acerca de la utilización de instrumentos de clasificación de pacientes en la práctica asistencial y de gestión en Brasil. Método Revisión integradora de la literatura con consulta a las bases de datos: Literatura Latinoamericana y del Caribe en Ciencias de la Salud (LILACS), Medical Literature Analysis and Retrieval System on-line (MEDLINE), Cumulative Index to Nursing and Allied Health Literature (CINAHL) y SCOPUS, relativas al período de enero de 2002 a diciembre de 2013. Resultados De las 1.194 publicaciones encontradas, 31 atendieron a los criterios de selección. Se observó una mayor cantidad de artículos en la categoría perfil asistencial y carga laboral (n=15), seguidos de la categoría evaluación de las propiedades psicométricas (n=14). Conclusión La producción nacional todavía no ha investigado algunas finalidades de utilización de instrumentos de clasificación de pacientes en la práctica profesional del enfermero. La identificación de áreas aún no exploradas podrá orientar futuras investigaciones acerca de la temática. .


Subject(s)
Humans , Bibliometrics , Nursing Process/statistics & numerical data , Brazil , Nursing Assessment/statistics & numerical data , Psychometrics , Reproducibility of Results
19.
Psicol. reflex. crit ; 27(1): 171-178, Jan.-Mar. 2014. tab
Article in English | Index Psychology - journals | ID: psi-67996

ABSTRACT

The purpose of this study is to analyze how family systems influence adolescents' suicidal ideation. The participants were 534 adolescents (51.1% female and 48.9% male), with ages ranging from 14 to 18 years (M=16.18; SD=1.14). The instruments used were the following: Family Adaptability and Cohesion Evaluation Scale, Psychological Separation Inventory and Questionnaire of Suicidal Ideation. Results have shown that adolescents with higher suicidal ideation belong to the so-called unbalanced families (with low cohesion and flexibility) and have a conflictual dependence to their parents. On the other hand, adolescents that belong to balanced families revealed lower suicidal ideation. In conclusion, the family's cohesion and flexibility are protective factors against adolescents' suicidal ideation.(AU)


O objetivo deste estudo é analisar de que forma o funcionamento familiar influencia a ideação suicida na adolescência. Para tal, analisámos a coesão e adaptabilidade familiar, assim como a independência conflitual. Participaram neste estudo 534 adolescentes (51,1% raparigas e 48,9% rapazes), com idades compreendidas entre 14 e 18 anos (M=16,18; DP=1,14). Os instrumentos utilizados foram: Escala de Adaptabilidade e Coesão Familiar; Inventário Separação Psicológica e Questionário Ideação Suicida. Os resultados mostraram que os adolescentes com maior ideação suicida pertencem a famílias desequilibradas (coesão e adaptabilidade baixa) e têm uma forte dependência conflitual a ambos os pais. Os adolescentes pertencentes a famílias equilibradas revelaram menor ideação suicida. A coesão e a capacidade adaptativa da família são fatores protetores da ideação suicida.(AU)


Subject(s)
Humans , Male , Female , Adolescent , Suicidal Ideation , Family/psychology , Family Relations
20.
Psicol. reflex. crit ; 27(1): 171-178, jan.-mar. 2014. tab
Article in English | LILACS | ID: lil-709999

ABSTRACT

The purpose of this study is to analyze how family systems influence adolescents' suicidal ideation. The participants were 534 adolescents (51.1% female and 48.9% male), with ages ranging from 14 to 18 years (M=16.18; SD=1.14). The instruments used were the following: Family Adaptability and Cohesion Evaluation Scale, Psychological Separation Inventory and Questionnaire of Suicidal Ideation. Results have shown that adolescents with higher suicidal ideation belong to the so-called unbalanced families (with low cohesion and flexibility) and have a conflictual dependence to their parents. On the other hand, adolescents that belong to balanced families revealed lower suicidal ideation. In conclusion, the family's cohesion and flexibility are protective factors against adolescents' suicidal ideation.


O objetivo deste estudo é analisar de que forma o funcionamento familiar influencia a ideação suicida na adolescência. Para tal, analisámos a coesão e adaptabilidade familiar, assim como a independência conflitual. Participaram neste estudo 534 adolescentes (51,1% raparigas e 48,9% rapazes), com idades compreendidas entre 14 e 18 anos (M=16,18; DP=1,14). Os instrumentos utilizados foram: Escala de Adaptabilidade e Coesão Familiar; Inventário Separação Psicológica e Questionário Ideação Suicida. Os resultados mostraram que os adolescentes com maior ideação suicida pertencem a famílias desequilibradas (coesão e adaptabilidade baixa) e têm uma forte dependência conflitual a ambos os pais. Os adolescentes pertencentes a famílias equilibradas revelaram menor ideação suicida. A coesão e a capacidade adaptativa da família são fatores protetores da ideação suicida.


Subject(s)
Humans , Male , Female , Adolescent , Family/psychology , Suicidal Ideation , Family Relations
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