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1.
Mutagenesis ; 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38520343

RESUMO

An ethanol extract of Piper auritum leaves (PAEE) inhibits the mutagenic effect of three food-borne aromatic amines (2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP); 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx); 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline (4,8-DiMeIQx) in the TA98 Salmonella typhimurium strain. Preincubation with MeIQx demonstrated in mutagenesis experiments that inhibition of Cytochrome P450 (CYP), as well as direct interaction between component(s) of the plant extract with mutagens, might account for the antimutagenic observed effect. Gas chromatography/mass spectrometry analysis revealed that safrole (50.7%), α-copaene (7.7%), caryophyllene (7.2%), ß-pinene (4.2%), γ-terpinene (4.1%) and pentadecane (4.1%) as the main components of PAEE. Piper extract and safrole were able to inhibit the rat liver microsomal CYP1A1 activity that participates in the amines metabolism, leading to the formation of the ultimate mutagenic/ molecules. According to this, safrole and PAEE inhibited MeIQx mutagenicity but not that of the direct mutagen 2-nitrofluorene. No mutagenicity of plant extract or safrole was detected. This study show that PAEE and its main component safrole are associate with the inhibition of heterocyclic amines activation due in part to the inhibition of CYP1A subfamily activity.

2.
Rev Med Chil ; 150(5): 672-681, 2022 May.
Artigo em Espanhol | MEDLINE | ID: mdl-37906769

RESUMO

BACKGROUND: Atmospheric pollution is a problem that causes great concern and health risks for the population and the earth, as it affects developed countries and third world countries. Locally, there are no studies that prove the fulfillment level of the restriction about the usage of residential firewood, considering that since 2014 there is a procedure called "The Environmental Decontamination Plan" in Valdivia (PDAV). AIM: To determine the fulfillment level of the restriction about residential firewood and its related factors. MATERIAL AND METHODS: The population study were 594 homes that were assigned randomly and proportionally according to 2 territorial areas (A and B) established in the PDAV. The sample's characteristics were described, comparison techniques were applied by subgroups (sociodemographic, home's structures and humidity's perception and percentage of the firewood) to identify factors related mainly with the fulfillment of measurements about firewood usage. RESULTS: 52% of households do not comply with the residential firewood use restriction measure, having sociodemographic factors related with this failure, such as schooling, health insurance and home structure. Besides, it is noted that the knowledge level of PDAV is associated with the accomplish level of restriction measures. When people know more about PDAV, there is a higher proportion of accomplishment. CONCLUSION: In more than half of the households, the restriction on the use of woodstove is not complied. The lack of knowledge of the population about the PDAV directly influences its compliance, which requires strategies to promote adherence to this program.


Assuntos
Características da Família , Humanos , Chile/epidemiologia
3.
Reprod Domest Anim ; 52 Suppl 2: 354-358, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27859771

RESUMO

The intent of this contribution is to provide an update of the progress we have made towards developing a method/treatment to permanently sterilize cats. Our approach employs two complementary methodologies: RNA interference (RNAi) to silence genes involved in the central control of reproduction and a virus-based gene therapy system intended to deliver RNAi selectively to the hypothalamus (where these genes are expressed) via the systemic administration of modified viruses. We selected the hypothalamus because it contains neurons expressing Kiss1 and Tac3, two genes essential for reproduction and fertility. We chose the non-pathogenic adeno-associated virus (AAV) as a vector whose tropism could be modified to target the hypothalamus. The issues that must be overcome to utilize this vector as a delivery vehicle to induce sterility include modification of the wild-type AAV to target the hypothalamic region of the brain with a simultaneous reduction in targeting of peripheral tissues and non-hypothalamic brain regions, identification of RNAi targets that will effectively reduce the expression of Kiss1 and Tac3 without off-target effects, and determination if neutralizing antibodies to the AAV serotype of choice are present in cats. Successful resolution of these issues will pave the way for the development of a powerful tool to induce the permanent sterility in cats.


Assuntos
Gatos , Anticoncepção/veterinária , Dependovirus , Inativação Gênica , Vetores Genéticos , Hipotálamo , Animais , Anticoncepção/métodos , Expressão Gênica/efeitos dos fármacos , Engenharia Genética/métodos , Engenharia Genética/veterinária , Infertilidade/etiologia , Infertilidade/veterinária , Kisspeptinas/antagonistas & inibidores , Kisspeptinas/genética , Neurocinina B/antagonistas & inibidores , Neurocinina B/genética , Interferência de RNA
4.
Mutat Res ; 829: 111881, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39191149

RESUMO

Apiole (1-allyl-2,5-dimethoxy-3,4-methylenedioxybenzene) and parsley leaves ethanolic extract containing it inhibit the rat liver microsomal ethoxy- and methoxyresorufin-O-deacetylase activities associated with cytochrome P450 (CYP) 1A1 and 1A2, respectively. Cytochrome P4501A subfamily metabolizes environmental mutagens and several drugs, leading to the formation of mutagenic metabolites. Docking analysis showed that residue Phe123 within the active site of the CYP1A1 enzyme is bound to apiole through a π/π stacking of its benzene ring. In the case of 1A2, its Phe226 interacts with the dioxolane ring of apiole. Furthermore, apiole behaves as a mixed-type inhibitor of bacterial human recombinant CYP1A1. To explore one of the possible biological implications of this inhibitory effect, we tested the capacity of apiole and the parsley ethanolic extract to interfere with the mutagenicity of the promutagen 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) metabolized by CYP1A subfamily. As expected, both apiole and the plant extract reduced the number of revertant colonies of Salmonella typhimurium TA98 Ames strain after exposure to MeIQx, reaching a 78 % and 100 % reduction, respectively. Neither apiol nor parsley extract were mutagenic to the TA98 strain. We speculate that consuming apiole, a constituent of edible herbs, in conjunction with the utilization of pharmaceuticals metabolized by the CYP1A subfamily, may result in herb-drug interactions. Furthermore, the consumption of apiole by individuals who regularly ingest fresh vegetables may contribute to the low incidence of cancer observed in those who adhere to such a dietary regimen.

5.
Plant Biol (Stuttg) ; 25(7): 1186-1195, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37703542

RESUMO

Plant spatial distribution is an important topic in ecology as it determines species coexistence and biodiversity dynamics. Usually, plants show clustered distributions in nature. Mistletoes are a good example of aggregated distributions, as they form dense aggregations due to several factors (availability of competent hosts, seed dispersal vectors, microclimate conditions). We analysed four native mistletoe species with divergent life histories and host ranges: Desmaria mutabilis and Tristerix corymbosus from the temperate rainforests of southern Chile; and Tristerix aphyllus and Tristerix verticillatus from the northern semi-desert zone. While T. corymbosus and T. verticillatus have a wide host range, T. aphyllus and D. mutabilis are specialists that can parasitize only a few plant species. We hypothesized that specialized species would be more aggregated due to ecological and environmental restrictions. We used heterogeneous Poisson models to quantify spatial aggregation. Three of the four mistletoe species were spatially clustered at both environments, with aggregation being stronger in the temperate rainforest of southern Chile and particularly in the host-specialist species. Our results suggest that environmental constraints are more important than ecological constraints (host range) in shaping mistletoe spatial structure. Mistletoe aggregated spatial distribution depends primarily on the environment that they inhabit, which conditions host spatial availability, and arrangement.


Assuntos
Erva-de-Passarinho , Viscum album , Biodiversidade , Floresta Úmida , Chile
6.
Sci Rep ; 13(1): 3271, 2023 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-36841864

RESUMO

By first-principles total-energy calculations, we investigated the thermodynamic stability of the MAX solid solution MoxV4-xAlC3 in the 0 ≤ x ≤ 4 range. Results evidence that lattice parameter a increases as a function of Mo content, while the c parameter reaches its maximum expansion at x = 2.5. After that, a contraction is noticed. Mo occupies VI sites randomly until the out-of-plane ordered Mo2V2AlC3 alloy is formed. We employed the Defect Formation Energy (DFE) formalism to evaluate the thermodynamic stability of the alloys. Calculations show five stable compounds. At V-rich conditions and from Mo-rich to Mo-moderated conditions, the pristine V4AlC3 MAX is stable. In the region of V-poor conditions, from Mo-rich to Mo-moderated growth conditions, the solid solutions with x = 0.5, 1, and 1.5 and the o-MAX Mo2V2AlC3 are thermodynamically stable. The line profiles of the Electron Localization Function and Bader charge analysis show that the V-C interaction is mainly ionic, while the Mo-C is covalent. Also, the exfoliation energy to obtain a MXene layer is ~ 0.4 eV/Å2. DFE also shows that MXenes exfoliated from the MAX phase with the same Mo content and atomic arrangement are thermodynamically stable. Our results get a deeper atomic scale understanding of the previously reported experimental evidence.

7.
Hum Reprod ; 27(11): 3249-58, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22888166

RESUMO

STUDY QUESTION: Is decorin (DCN), a putative modulator of growth factor (GF) signaling, expressed in the primate ovary and does it play a role in ovarian biology? SUMMARY ANSWER: DCN expression in the theca, the corpus luteum (CL), its presence in the follicular fluid (FF) and its actions revealed in human IVF-derived granulosa cells (GCs), suggest that it plays multiple roles in the ovary including folliculogenesis, ovulation and survival of the CL. WHAT IS KNOWN ALREADY: DCN is a secreted proteoglycan, which has a structural role in the extracellular matrix (ECM) and also interferes with the signaling of multiple GF/GF receptors (GFRs). However, DCN expression and action in the primate ovary has yet to be determined. STUDY DESIGN, SIZE, DURATION: Archival human and monkey ovarian samples were analyzed. Studies were conducted using FF and GC samples collected from IVF patients. PARTICIPANTS/MATERIALS, SETTING, METHODS: Immunohistochemistry, western blotting, RT-PCR, quantitative RT-PCR (qPCR) and enzyme-linked immunosorbent assay (ELISA) studies were complemented by cellular studies, including the measurements of intracellular Ca²âº, reactive oxygen species (ROS), epidermal GF receptor (EGFR) phosphorylation by DCN and caspase activity. MAIN RESULTS AND THE ROLE OF CHANCE: Immunohistochemistry revealed strong DCN staining in the connective tissue and follicular thecal compartments, but not in GCs of pre-antral and antral follicles. Pre-ovulatory follicles could not be studied, but DCN was associated with connective tissue of CL samples and the cytoplasm of luteal cells. DCN expression in monkey CL doubled (P < 0.05) towards the end of the luteal lifespan. DCN was found in human FF obtained from IVF patients (mean: 12.9 ng/ml; n = 20) as determined by ELISA. DCN mRNA and/or protein were detected in freshly isolated and cultured, luteinized human GCs. In the latter, exogenous human recombinant DCN increased intracellular Ca²âº levels and induced the production of ROS in a concentration-dependent manner. DCN, like epidermal GF, phosphorylated EGFR significantly (P < 0.05) and reduced the activity of caspase 3/7 in cultured GCs. The data indicate the expression of DCN in the theca of growing follicles, in FF of ovulatory follicles and in the CL. Therefore, DCN may exert paracrine actions via GF/GFR systems in multiple ovarian compartments. LIMITATIONS, REASONS FOR CAUTION: Functional studies were performed in cultures of human luteinized GCs, which are an apt model but may not fully mirror the pre-ovulatory GC compartment or the CL. Other human ovarian cells, including the thecal cells, were not available. WIDER IMPLICATIONS OF THE FINDINGS: In accordance with its evolving roles in other organs, ovarian DCN is an ECM-associated component, which acts as a multifunctional regulator of GF signaling in the primate ovary. DCN may thus be involved in folliculogenesis, ovulation and the regulation of the CL survival in primates. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by Deutsche Forschungsgemeinschaft (DFG) MA1080/17-3 and in part DFG MA1080/21-1 (to AM), NIH grants HD24870 (S.R.O. and R.L.S.), the Eunice Kennedy Shriver NICHD/NIH through cooperative agreement HD18185 as part of the Specialized Cooperative Centers Program in Reproduction and Infertility Research (S.R.O.) and 8P51OD011092-53 for the operation of the Oregon National Primate Research Center (G.A.D., J.D.H., S.R.O. and R.L.S).


Assuntos
Decorina/metabolismo , Matriz Extracelular/metabolismo , Fase Luteal/metabolismo , Oogênese , Ovário/metabolismo , Ovulação/metabolismo , Adulto , Animais , Células Cultivadas , Corpo Lúteo/citologia , Corpo Lúteo/metabolismo , Decorina/genética , Receptores ErbB/metabolismo , Feminino , Líquido Folicular/metabolismo , Regulação da Expressão Gênica , Células da Granulosa/citologia , Células da Granulosa/metabolismo , Humanos , Macaca mulatta , Ovário/citologia , Fosforilação , Processamento de Proteína Pós-Traducional , RNA Mensageiro/metabolismo , Células Tecais/citologia , Células Tecais/metabolismo
8.
Reprod Domest Anim ; 47 Suppl 4: 228-32, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22827375

RESUMO

A non-surgical method to induce sterility would be a useful tool to control feral populations of animals. Our laboratories have experience with approaches aimed at targeting brain cells in vivo with vehicles that deliver a payload of either inhibitory RNAs or genes intended to correct cellular dysfunction. A combination/modification of these methods may provide a useful framework for the design of approaches that can be used to sterilize cats and dogs. For this approach to succeed, it has to meet several conditions: it needs to target a gene essential for fertility. It must involve a method that can selectively silence the gene of interest. It also needs to deliver the silencing agent via a minimally invasive method. Finally, the silencing effect needs to be sustained for many years, so that expansion of the targeted population can be effectively prevented. In this article, we discuss this subject and provide a succinct account of our previous experience with: (i) molecular reagents able to disrupt reproductive cyclicity when delivered to regions of the brain involved in the control of reproduction and (ii) molecular reagents able to ameliorate neuronal disease when delivered systemically using a novel approach of gene therapy.


Assuntos
Interferência de RNA/fisiologia , Esterilização Reprodutiva/veterinária , Adenoviridae , Animais , Gatos , Cães , Feminino , Fertilidade/fisiologia , Vetores Genéticos , Hipotálamo/fisiologia , Infertilidade Feminina , Masculino , MicroRNAs , Controle da População , Primatas , Ratos , Esterilização Reprodutiva/métodos
9.
Reprod Domest Anim ; 47 Suppl 6: 381-6, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23279544

RESUMO

Population control of feral animals is often difficult, as it can be dangerous for the animals, labour intensive and expensive. Therefore, a useful tool for control of animal populations would be a non-surgical method to induce sterility. Our laboratories utilize methods aimed at targeting brain cells in vivo with vehicles that deliver a payload of either inhibitory RNAs or genes intended to correct cellular dysfunction. A useful framework for design of a new approach will be the combination of these methods with the intended goal to produce a technique that can be used to non-invasively sterilize cats and dogs. For this approach to succeed, it has to meet several conditions: the target gene must be essential for fertility; the method must include a mechanism to effectively and specifically silence the gene of interest; the method of delivering the silencing agent must be minimally invasive, and finally, the silencing effect must be sustained for the lifespan of the target species, so that expansion of the population can be effectively prevented. In this article, we discuss our work to develop gene silencing technology to induce sterility; we will use examples of our previous studies demonstrating that this approach is viable. These studies include (i) the use of viral vectors able to disrupt reproductive cyclicity when delivered to the regions of the brain involved in the control of reproduction and (ii) experiments with viral vectors that are able to ameliorate neuronal disease when delivered systemically using a novel approach of gene therapy.


Assuntos
Gatos , Anticoncepção/veterinária , Cães , Inativação Gênica/fisiologia , Esterilização Reprodutiva/veterinária , Animais , Anticoncepção/métodos , Feminino , Fertilidade/fisiologia , Hipotálamo/fisiologia , Masculino , MicroRNAs , Controle da População , Esterilização Reprodutiva/métodos
10.
Sci Rep ; 11(1): 12393, 2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34117283

RESUMO

In this work, we demonstrate, through first-principles calculations, the existence of a new family of copper-based MXenes. These add up new structures to the previously reported universe and span the interest of such 2D materials for applications in heterogeneous catalysis, ion-based batteries, sensors, biomedical applications, and so on. First, we propose the MXene-like structures: Cu2N, Cu2C, and Cu2O. Phonon spectra calculations confirmed their dynamical stability by showing just positive frequencies all through the 2D Brillouin zone. The new MXenes family displays metallic characteristics, mainly induced by the Cu-3d orbitals. Bader charge analysis and charge density differences depict bonds with ionic character in which Cu is positively charged, and the non-metal atom gets an anionic character. Also, we investigate the functionalization of the proposed structures with Cl, F, O, and OH groups. Results show that the H3 site is the most favorable for functionalization. In all cases, the non-magnetic nature and metallic properties of the pristine MXenes remain. Our results lay the foundations for the experimental realization of a new MXenes family.

11.
Ann Rheum Dis ; 69(6): 1136-9, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19687018

RESUMO

OBJECTIVES: To assess the changes in carotid intima-media thickness (IMT) and the associated risks factors in patients with low severity systemic lupus erythematosus (SLE). METHODS: Common carotid IMT measurements were obtained by ultrasound from 101 patients with SLE at an interval of 2 years. Cardiovascular risk factors, disease activity, accumulated damage, severity (Katz index) and biochemical parameters (including high sensitivity C-reactive protein, interleukin 6, C3a, C4a, C5a and homocysteine) were also assessed. Multiple linear regression was used to assess the effect of these variables on the end IMT measurement (eIMT) adjusted to the baseline measurement (bIMT). RESULTS: The cohort comprised 94.1% women, with a mean age at entry of 41.5 years and a mean disease duration of 12.1 years. An increase of 0.078 mm in IMT was detected over 2 years, from a mean bIMT of 0.37 mm to a mean eIMT of 0.44 mm (p<0.001). When adjusted for the bIMT, multiple linear regression identified bIMT, age at diagnosis, homocysteine, C3 and C5a as risk factors for IMT progression. CONCLUSIONS: IMT significantly increases over 2 years in patients with SLE. Age, baseline IMT, C3, C5a anaphylatoxin and homocysteine are all associated risk factors, supporting a role for complement and homocysteine in the early stages of premature SLE-associated atherosclerosis.


Assuntos
Aterosclerose/etiologia , Lúpus Eritematoso Sistêmico/complicações , Adulto , Idoso , Aterosclerose/diagnóstico por imagem , Aterosclerose/patologia , Biomarcadores/sangue , Artéria Carótida Primitiva/diagnóstico por imagem , Artéria Carótida Primitiva/patologia , Complemento C5a/metabolismo , Progressão da Doença , Métodos Epidemiológicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Túnica Íntima/diagnóstico por imagem , Túnica Íntima/patologia , Túnica Média/diagnóstico por imagem , Túnica Média/patologia , Ultrassonografia Doppler , Adulto Jovem
12.
Hum Reprod ; 25(4): 969-76, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20097922

RESUMO

BACKGROUND: Oxytocin (OT) is produced by granulosa cells (GCs) of pre-ovulatory ovarian follicles and the corpus luteum (CL) in some mammalian species. Actions of OT in the ovary have been linked to luteinization, steroidogenesis and luteolysis. Human IVF-derived (h)GCs possess a functional OT receptor (OTR), linked to elevation of intracellular Ca(2+), but molecular identity of the receptor for OT in human granulosa cells (hGCs) and down-stream consequences are not known. METHODS AND RESULTS: RT-PCR, sequencing and immunocytochemistry identified the genuine OTR in hGCs. OT (10 nM-10 microM) induced elevations of intracellular Ca(2+) levels (Fluo-4 measurements), which were blocked by tocinoic acid (TA; 50 microM, a selective OTR-antagonist). Down-stream effects of OTR-activation include a concentration dependent decrease in cell viability/metabolism, manifested by reduced ATP-levels, increased caspase3/7-activity (P < 0.05) and electron microscopical signs of cellular regression. TA blocked all of these changes. Immunoreactive OTR was found in the CL and GCs of large and, surprisingly, also small pre-antral follicles of the human ovary. Immunoreactive OTR in the rhesus monkey ovary was detected in primordial and growing primary follicles in the infantile ovary and in follicles at all stages of development in the adult ovary, as well as the CL: these results were corroborated by RT-PCR analysis of GCs excised by laser capture microdissection. CONCLUSIONS: Our study identifies genuine OTRs in human and rhesus monkey GCs. Activation by high levels of OT leads to cellular regression in hGCs. As GCs of small follicles also express OTRs, OT may have as yet unknown functions in follicular development.


Assuntos
Apoptose/genética , Apoptose/fisiologia , Células da Granulosa/citologia , Células da Granulosa/metabolismo , Macaca mulatta/genética , Macaca mulatta/metabolismo , Ovário/citologia , Ovário/metabolismo , Receptores de Ocitocina/genética , Receptores de Ocitocina/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Sequência de Bases , Sinalização do Cálcio , Corpo Lúteo/citologia , Corpo Lúteo/metabolismo , Primers do DNA/genética , Feminino , Humanos , Imuno-Histoquímica , Técnicas In Vitro , Microscopia Eletrônica de Transmissão , Ocitocina/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Especificidade da Espécie
13.
Mutagenesis ; 25(3): 249-55, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20118186

RESUMO

Bacterial nitroreductases (NRs) catalyse the oxygen-insensitive reduction of several nitro-substituted compounds and quinones. SnrA and cnr NRs have been previously identified in Salmonella enterica serovar Typhimurium; they reduce several environmental nitro compounds that display mutagenic activity in the Ames test. Although some of their biochemical properties have been reported, the substrate specificity of each protein over mutagenic nitro compounds is unknown; even more, the possible relationship between their capacity to activate nitro compounds into mutagens and the redox properties of putative substrates has been poorly investigated. We have purified SnrA and cnr and investigated their capacity to activate several mutagens in the Ames test as well as their kinetic parameters K(m) and V(max). Our results show that SnrA and cnr are able to activate 2,7-dinitrofluorene with the same efficiency and a similar mutagenic potency in the YG7132 tester strain; 1-nitropyrene and 1,3-dinitropyrene were efficiently activated by cnr, whereas 1,8-dinitropyrene, 1,6-dinitropyrene and 2-nitrofluorene were scarcely activated by either NR. The mutagenic potency of nitro compounds obtained in the presence of either enzyme correlates with their redox potential reported in the literature. On the other hand, a good correlation was obtained between the catalytic efficiency (V(max)/K(m)) of the purified cnr with the redox potential of eight molecules including nitro-substituted compounds and quinones. No correlation between redox potential and catalytic efficiency by SnrA was observed, suggesting that factors other than redox potential such as the structure of the compounds are involved in the catalytic efficiency of SnrA.


Assuntos
Proteínas de Bactérias/metabolismo , Hidrocarbonetos Aromáticos/toxicidade , Nitrocompostos/toxicidade , Nitrorredutases/metabolismo , Quinonas/toxicidade , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/enzimologia , Proteínas de Bactérias/isolamento & purificação , Biocatálise/efeitos dos fármacos , Técnicas Eletroquímicas , Ativação Enzimática/efeitos dos fármacos , Cinética , Testes de Mutagenicidade , Nitrorredutases/isolamento & purificação , Oxirredução/efeitos dos fármacos
14.
Scand J Rheumatol ; 39(5): 409-12, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20560809

RESUMO

OBJECTIVE: To determine the value of ultrasonography in the assessment of patients with idiopathic carpal tunnel syndrome (CTS) and poor outcome after carpal tunnel release. METHODS: A total of 88 consecutive patients with CTS (104 hands) underwent open surgical release of the median nerve. Ultrasound (US) examination was performed blind to any patient's data. The median nerve area at tunnel inlet and outlet, the retinaculum distance, and the flattening ratio were measured. The main outcome variable was the patient's overall satisfaction using a five-point Likert scale (1 = worse, 2 = no change, 3 = slightly better, 4 = much better, 5 = cured) at 3 months postoperatively. Pre- and postoperative ultrasonographic findings in relation to clinical outcome were analysed. RESULTS: Improvement (scores 4 or 5 on the Likert scale) was recorded in 75 hands (72%). After carpal tunnel release, the cross-sectional area at tunnel inlet decreased from a mean of 14.2 to 13.3 mm2 in the group with clinical improvement and also from a mean of 12.5 to 11.6 mm2 in the group with no change or slight improvement. No significant changes in the cross-sectional area at tunnel outlet, retinaculum distance, and flattening ratio were observed. CONCLUSION: Reduction of the median nerve cross-sectional area at tunnel inlet at 3 months after carpal tunnel release was similar in patients reporting cure or great improvement and in those with slight or no improvement. Ultrasonography is of limited value in assessment of patients with poor outcome after median nerve release.


Assuntos
Articulações do Carpo/diagnóstico por imagem , Articulações do Carpo/cirurgia , Síndrome do Túnel Carpal/diagnóstico por imagem , Síndrome do Túnel Carpal/cirurgia , Avaliação de Resultados em Cuidados de Saúde/métodos , Adulto , Síndrome do Túnel Carpal/diagnóstico , Feminino , Humanos , Masculino , Nervo Mediano/diagnóstico por imagem , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Falha de Tratamento , Resultado do Tratamento , Ultrassonografia
15.
Brain Res Bull ; 163: 57-64, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32707261

RESUMO

Cytochrome P450 (CYP) epoxygenases have been considered the main producers of epoxyeicosatrienoic acids (EETs) through the oxidation of arachidonic acid (AA). EETs display various biological properties, notably their powerful anti-inflammatory activities. In the brain, EETs have proven to be neuroprotective and to improve neuroinflammation. However, it is known that inflammation could modify CYP expression. We have previously reported that an inflammatory process in astrocytes is able to down-regulate CYP2J3 and CYP2C11 mRNA, protein levels, and activity (Navarro-Mabarak et al., 2019). In this work, we evaluated the effect of neuroinflammation in protein expression of CYP epoxygenases in the brain. Neuroinflammation was induced by the intraperitoneal administration of LPS (1 mg/kg) to male Wistar rats and was corroborated by IL-6, GFAP, and Iba-1 protein levels in the cortex over time. CYP2J3 and CYP2C11 protein levels were also evaluated in the cortex after 6, 12, 24, 48, and 72 h of LPS treatment. Our results show for the first time that neuroinflammation is able to downregulate CYP2J3 and CYP2C11 protein expression in the brain cortex.


Assuntos
Hidrocarboneto de Aril Hidroxilases/metabolismo , Encéfalo/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Família 2 do Citocromo P450/metabolismo , Regulação para Baixo/fisiologia , Mediadores da Inflamação/metabolismo , Esteroide 16-alfa-Hidroxilase/metabolismo , Animais , Hidrocarboneto de Aril Hidroxilases/antagonistas & inibidores , Encéfalo/efeitos dos fármacos , Família 2 do Citocromo P450/antagonistas & inibidores , Regulação para Baixo/efeitos dos fármacos , Lipopolissacarídeos/toxicidade , Masculino , Ratos , Ratos Wistar , Esteroide 16-alfa-Hidroxilase/antagonistas & inibidores
16.
Toxicol Lett ; 330: 90-95, 2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32416225

RESUMO

The Cytochrome P450 (CYP) enzyme family comprises a wide array of monooxygenases involved in the oxidation of endobiotic and xenobiotic molecules. The active site of a CYP enzyme contains an iron protoporphyrin center coordinated to a cysteine thiolate, and then, molecular oxygen is associated with the iron to be converted into dioxygen complex plus substrate. Reduction by CYP reductase expedites hydroxylation of the compound. In this oxidation reaction, insufficient oxygen molecules would affect enzyme catalysis. Nevertheless, biochemical data about CYP kinetics at low oxygen concentrations are not available. In this work, we present the results on the variation in rat liver microsomal CYP Vmax app and Km app under normal and hypoxic conditions. Using alkoxyresorufin molecules as substrates, the Vmax/Km ratios for resorufin production decreased from 426 to 393 for CYP1A1 and from 343 to 202 for CYP2B1 at a low oxygen concentration (4.1 ppm) compared to the ratios observed at a normal oxygen concentration (6.5 ppm). Additionally, the bacterial mutagenicity of 2-aminoanthracene and cyclophosphamide, decreased by 32% and 42%, respectively, at low oxygen concentrations. These results support the hypothesis that low oxygen availability is implicated in the low efficiency of substrate oxidation by CYP.

17.
Arch Osteoporos ; 15(1): 63, 2020 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-32335759

RESUMO

The coordination of Fracture Liaison Services (FLS) with Primary Care (PC) is necessary for the continuity of care of patients with fragility fractures. This study proposes a Best Practice Framework (BPF) and performance indicators for the implementation and follow-up of FLS-PC coordination in clinical practice in Spain. PURPOSE: To develop a BPF for the coordination of FLS with PC in Spain and to improve the continuity of care for patients with fragility fractures. METHODS: A Steering Committee selected experts from seven Spanish FLS and related PC doctors and nurses to participate in a best practice workshop. Selection criteria were an active FLS with an identified champion and prior contact with PC centres linked to the hospital. The main aim of the workshop was to review current FLS practices in Spain and their integration with PC. A BPF document with processes, tools, roles, and metrics was then generated. RESULTS: Spanish FLS consists of a multidisciplinary team of physicians/nurses but with low participation of other professionals and PC staff. Evaluation and treatment strategies are widely variable. Four desired standards were agreed upon: (1) Effective channels for FLS-PC communication; (2) minimum contents of an FLS clinical report and its delivery to PC; (3) adherence monitoring 3 months after FLS baseline visit; and (4) follow-up by PC. Proposed key performance indicators are (a) number of FLS-PC communications, including consensus protocols; (b) confirmation FLS report received by PC; (c) medical/nursing PC appointment after FLS report received; and (d) number of training sessions in PC. CONCLUSIONS: The BPF provides a comprehensive approach for FLS-PC coordination in Spain, to promote the continuity of care in patients with fragility fractures and improve secondary prevention. The implementation of BPF recommendations and performance indicator tracking will benchmark best FLS practices in the future.


Assuntos
Benchmarking , Continuidade da Assistência ao Paciente/normas , Fraturas por Osteoporose/terapia , Guias de Prática Clínica como Assunto , Atenção Primária à Saúde/normas , Feminino , Implementação de Plano de Saúde , Humanos , Masculino , Espanha
18.
Science ; 181(4101): 760-1, 1973 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-4724933

RESUMO

Prostaglandin E(2) (PGE(2)) injected into the third ventricle of ovariectomized rats increased plasma luteinizing hormone dramatically and follicle stimulating hormone slightly. PGE(1) elevated prolactin; PGF(1alpha) or PGF(2alpha) had no effect. PGE(2) or PGE(1) injected directly into the anterior pituitary were ineffective. These results suggest that specific prostaglandins act at the hypothalamus to control pituitary hormone release.


Assuntos
Hormônio Foliculoestimulante/sangue , Hipotálamo/fisiologia , Hormônio Luteinizante/sangue , Prolactina/sangue , Prostaglandinas/fisiologia , Animais , Castração , Ventrículos Cerebrais , Feminino , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Injeções , Hipófise , Prostaglandinas/administração & dosagem , Prostaglandinas/farmacologia , Radioimunoensaio , Ratos
19.
Clin Exp Rheumatol ; 27(5): 786-93, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19917161

RESUMO

OBJECTIVES: To assess the usefulness of clinical findings, nerve conduction studies and ultrasonography performed by a rheumatologist to predict success in patients with idiopathic carpal tunnel syndrome (CTS) undergoing median nerve release. METHODS: Ninety consecutive patients with CTS (112 wrists) completed a specific CTS questionnaire and underwent physical examination and nerve conduction studies. Ultrasound examination was performed by a rheumatologist who was blind to any patient's data. Outcome variables were improvement >25% in symptoms of the CTS questionnaire and patient's overall satisfaction (5-point Likert scale) at 3 months postoperatively. Success was defined as improvement in both outcome variables. Receiver operating characteristics (ROC) curves and logistic regression analyses were used to assess the best predictive combination of preoperative findings. RESULTS: Success was achieved in 63% of the operated wrists. Utility parameters and area under the ROC curve (AUC) for individual findings was poor, ranging from 0.481 of the nerve conduction study to 0.634 of the cross-sectional area at tunnel outlet. Logistic regression identified the preoperative US parameters as the best predictive variables for success after 3 months. The best predictive combination (AUC=0.708) included a negative Phalen maneuver, plus absence of thenar atrophy, plus less than moderately abnormalities on nerve conduction studies plus a large maximal cross-sectional area along the tunnel by ultrasonography. CONCLUSION: Although cross-sectional area of the median nerve was the only predictor of success after three months of surgical release, isolated preoperative findings are not reliable predictors of success in patients with idiopathic CTS. A combination of findings that include ultrasound improves prediction.


Assuntos
Síndrome do Túnel Carpal/diagnóstico por imagem , Síndrome do Túnel Carpal/cirurgia , Eletrodiagnóstico , Nervo Mediano/diagnóstico por imagem , Índice de Gravidade de Doença , Adulto , Síndrome do Túnel Carpal/reabilitação , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Exame Físico , Estudos Prospectivos , Curva ROC , Recuperação de Função Fisiológica , Ultrassonografia
20.
Neuron ; 9(4): 657-70, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1327011

RESUMO

Hypothalamic injury causes female sexual precocity by activating luteinizing hormone-releasing hormone (LHRH) neurons, which control sexual development. Transforming growth factor-alpha (TGF-alpha) has been implicated in this process, but its involvement in normal sexual maturation is unknown. The present study addresses this issue. TGF-alpha mRNA and protein were found mostly in astroglia, in regions of the hypothalamus concerned with LHRH control. Hypothalamic TGF-alpha mRNA levels increased at times when secretion of pituitary gonadotropins--an LHRH-dependent event--was elevated, particularly at the time of puberty. Gonadal steroids involved in the control of LHRH secretion increased TGF-alpha mRNA levels. Blockade of TGF-alpha action in the median eminence, a site of glial-LHRH nerve terminal association, delayed puberty. These results suggest that TGF-alpha of glial origin is a component of the developmental program by which the brain controls mammalian sexual maturation.


Assuntos
Hormônio Liberador de Gonadotropina/metabolismo , Hipotálamo/fisiologia , RNA Mensageiro/metabolismo , Maturidade Sexual/fisiologia , Fator de Crescimento Transformador alfa/genética , Tirfostinas , Animais , Elementos Antissenso (Genética) , Catecóis/administração & dosagem , Catecóis/farmacologia , Implantes de Medicamento , Receptores ErbB/antagonistas & inibidores , Estradiol/farmacologia , Feminino , Expressão Gênica , Hipotálamo/efeitos dos fármacos , Hipotálamo/crescimento & desenvolvimento , Eminência Mediana/efeitos dos fármacos , Eminência Mediana/crescimento & desenvolvimento , Eminência Mediana/fisiologia , Nitrilas/administração & dosagem , Nitrilas/farmacologia , Ovariectomia , Proteínas Tirosina Quinases/antagonistas & inibidores , Ratos , Ratos Sprague-Dawley
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