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1.
Int J Mol Sci ; 25(11)2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38892404

RESUMO

Reproductive failure in dogs is often due to unknown causes, and correct diagnosis and treatment are not always achieved. This condition is associated with various congenital and acquired etiologies that develop inflammatory processes, causing an increase in the number of leukocytes within the female reproductive tract (FRT). An encounter between polymorphonuclear neutrophils (PMNs) and infectious agents or inflammation in the FRT could trigger neutrophil extracellular traps (NETs), which are associated with significantly decreased motility and damage to sperm functional parameters in other species, including humans. This study describes the interaction between canine PMNs and spermatozoa and characterizes the release of NETs, in addition to evaluating the consequences of these structures on canine sperm function. To identify and visualize NETs, May-Grünwald Giemsa staining and immunofluorescence for neutrophil elastase (NE) were performed on canine semen samples and sperm/PMN co-cultures. Sperm viability was assessed using SYBR/PI and acrosome integrity was assessed using PNA-FITC/PI by flow cytometry. The results demonstrate NETs release in native semen samples and PMN/sperm co-cultures. In addition, NETs negatively affect canine sperm function parameters. This is the first report on the ability of NETs to efficiently entrap canine spermatozoa, and to provide additional data on the adverse effects of NETs on male gametes. Therefore, NETs formation should be considered in future studies of canine reproductive failure, as these extracellular fibers and NET-derived pro-inflammatory capacities will impede proper oocyte fertilization and embryo implantation. These data will serve as a basis to explain certain reproductive failures of dogs and provide new information about triggers and molecules involved in adverse effects of NETosis for domestic pet animals.


Assuntos
Armadilhas Extracelulares , Neutrófilos , Espermatozoides , Animais , Cães , Armadilhas Extracelulares/metabolismo , Masculino , Espermatozoides/metabolismo , Neutrófilos/metabolismo , Motilidade dos Espermatozoides , Feminino , Elastase de Leucócito/metabolismo , Técnicas de Cocultura , Acrossomo/metabolismo
2.
BMC Psychiatry ; 20(1): 138, 2020 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-32228548

RESUMO

BACKGROUND: This study aimed to determine conditional dependence relationships of variables that contribute to psychological vulnerability associated with suicide risk. A Bayesian network (BN) was developed and applied to establish conditional dependence relationships among variables for each individual subject studied. These conditional dependencies represented the different states that patients could experience in relation to suicidal behavior (SB). The clinical sample included 650 mental health patients with mood and anxiety symptomatology. RESULTS: Mainly indicated that variables within the Bayesian network are part of each patient's state of psychological vulnerability and have the potential to impact such states and that these variables coexist and are relatively stable over time. These results have enabled us to offer a tool to detect states of psychological vulnerability associated with suicide risk. CONCLUSION: If we accept that suicidal behaviors (vulnerability, ideation, and suicidal attempts) exist in constant change and are unstable, we can investigate what individuals experience at specific moments to become better able to intervene in a timely manner to prevent such behaviors. Future testing of the tool developed in this study is needed, not only in specialized mental health environments but also in other environments with high rates of mental illness, such as primary healthcare facilities and educational institutions.


Assuntos
Ansiedade/psicologia , Inteligência Artificial , Transtornos do Humor/psicologia , Ideação Suicida , Tentativa de Suicídio/psicologia , Adolescente , Adulto , Teorema de Bayes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
3.
Cryobiology ; 97: 5-11, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33121933

RESUMO

Saccharides have bioprotective properties, with a high capacity to preserve biological proteins and membranes during sperm cryopreservation. The aim of this study was to evaluate how replacing the lactose of cryopreservation media by sucrose (SUC) or trehalose (TRE) at concentrations of 0.2 M (SUC-1 and TRE-1) and 0.25 M (SUC-2 and TRE-2) affects frozen/thawed pig spermatozoa. The media used were composed of medium A (saccharide/egg yolk) and B (saccharide/egg yolk/glycerol), their osmolality being determined prior to freezing. Cell viability, membrane lipid disorder, acrosome integrity, mitochondrial membrane potential (MMP), lipid peroxidation, thiol group oxidation, total reactive oxygen species (ROS), peroxynitrite and superoxide anion (O2●-) were determined through flow cytometry; total motility (TM), progressive motility (PM) and kinetic parameters motility were determined immediately after thawing (T0) and again 30 (T30) and 60 (T60) minutes later. The SUC-2 and TRE-2 groups maintained viability significantly and presented fewer lipid membrane disorders, respectively, both with a significant increase in MMP. The production of O2●- and peroxynitrite was lower in the TRE-2 groups compared to the control (P < 0.05). Total motility at T0 was greater in the TRE-2 group (P < 0.05). Sperm kinetics was not affected by the treatment. The use of saccharides SUC and TRE at a concentration of 0.25 M improves sperm quality, so that both non-penetrating cryoprotectants can be utilized in pig sperm freezing media.


Assuntos
Preservação do Sêmen , Animais , Criopreservação/métodos , Crioprotetores/farmacologia , Congelamento , Masculino , Estresse Oxidativo , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides , Espermatozoides , Suínos
4.
Antioxidants (Basel) ; 12(6)2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37372002

RESUMO

Excessive levels of reactive nitrogen species (RNS), such as peroxynitrite, promote nitrosative stress, which is an important cause of impaired sperm function. The metalloporphyrin FeTPPS is highly effective in catalyzing the decomposition of peroxynitrite, reducing its toxic effects in vivo and in vitro. FeTPPS has significant therapeutic potential in peroxynitrite-related diseases; however, its effects on human spermatozoa under nitrosative stress have not been described. This work aimed to evaluate the in vitro effect of FeTPPS against peroxynitrite-mediated nitrosative stress in human spermatozoa. For this purpose, spermatozoa from normozoospermic donors were exposed to 3-morpholinosydnonimine, a molecule that generates peroxynitrite. First, the FeTPPS-mediated peroxynitrite decomposition catalysis was analyzed. Then, its individual effect on sperm quality parameters was evaluated. Finally, the effect of FeTPPS on ATP levels, motility, mitochondrial membrane potential, thiol oxidation, viability, and DNA fragmentation was analyzed in spermatozoa under nitrosative stress conditions. The results showed that FeTPPS effectively catalyzes the decomposition of peroxynitrite without affecting sperm viability at concentrations up to 50 µmol/L. Furthermore, FeTPPS mitigates the deleterious effects of nitrosative stress on all sperm parameters analyzed. These results highlight the therapeutic potential of FeTPPS in reducing the negative impact of nitrosative stress in semen samples with high RNS levels.

5.
Res Vet Sci ; 164: 105028, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37804665

RESUMO

In cattle, clinical and subclinical inflammation in the bovine female reproductive tract (FRT) significantly reduces fertility. PMN participate in this FRT-associated inflammation by eliminating pathogens by eliciting various defense mechanisms, with the release of neutrophil extracellular traps NETs) being the latest process discovered. Consistently, human-, bovine- and porcine-derived spermatozoa induce release of NETs in exposed PMN of the same species origin, and thereby decreasing sperm motility through NETs-mediated entrapment. The release of NETs in the presence of different sperm sub-populations is evaluated in this work. Cryopreserved bovine sperm were selected and different sperm populations were used: viable sperm, sperm with oxidative stress, capacitated sperm, and sperm with loss of viability. Isolated PMN of dairy cows were co-incubated with these sperm populations for 4 h. Neutrophil elastase (NE) and DNA were detected by fluorescence microscopy analysis. It was noted that exposed bovine PMN released NETs in the presence of sperm. Moreover, sperm-triggered NETosis resulted different phenotypes of NETs, i. e. spread NETs (sprNETs), diffused NETs (diffNETs) and aggregated NETs (aggNETs). Viable/motile spermatozoa induced a higher proportion of NETotic cells at 15, 60 and 120 min in comparison to controls. In conclusion, all bovine sperm populations in co-culture with PMN generated NETs extrusion while viable sperm activated NETotic cells to a greater extent. With this being an early event in the activation of bovine PMN.


Assuntos
Doenças dos Bovinos , Armadilhas Extracelulares , Doenças dos Suínos , Bovinos , Masculino , Animais , Feminino , Humanos , Suínos , Armadilhas Extracelulares/fisiologia , Neutrófilos , Sêmen , Motilidade dos Espermatozoides , Espermatozoides , Inflamação/veterinária
6.
J Man Manip Ther ; 30(4): 207-227, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35067217

RESUMO

OBJECTIVE: To systematically review the effects of treatment-based classification (TBC) in patients with specific and nonspecific acute, subacute and chronic low back pain. METHODS: The following databases were searched: MEDLINE, EMBASE, PsycINFO, Global Health, CENTRAL, Web of Science, CINAHL, SPORTDiscus, PEDro and WHO from inception up to December 2021. We used the PEDro scale, the TIDieR checklist and the GRADE approach to evaluate the risk of bias, quality on reporting and the certainty of the evidence, respectively. RESULTS: Twenty-three trials (pooled n = 2,649) met the inclusion criteria. We have identified a total of 22 comparisons and 134 estimates of treatment effects. There was a very large heterogeneity with regards to the comparison groups. Most of individual trials had low risk of bias with a mean score of 6.8 (SD = 1.3) on a 0-10 scale. The certainty of evidence for most comparisons was low, which indicates that more high quality and robust trials are needed. We were able to pool the data using a meta-analysis approach for only two comparisons (TBC versus mobility exercises in patients with acute low back pain and traction for patients with sciatica). In general, the TBC approach seems to be useful for patients with acute low back pain, sciatica and with spinal stenosis. We strongly suggest readers to carefully read our summary of findings table for further details on each comparison. CONCLUSION: The TBC approach seems to be useful for patients with acute low back pain, sciatica and with spinal stenosis.


Assuntos
Dor Aguda , Dor Lombar , Ciática , Estenose Espinal , Terapia por Exercício , Humanos , Dor Lombar/terapia , Ciática/terapia
7.
Animals (Basel) ; 12(10)2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35625154

RESUMO

Neutrophil extracellular traps (NETs) play a key role in fertilisation by eliminating microorganisms and entrapping spermatozoa in the female reproductive tract (FRT). The deleterious effects of NETs on spermatozoa have been previously described; however, individual exposure to NET-derived components in bull spermatozoa has not been explored. The aim of this study was to evaluate the effects of the main NET-derived proteins, histone 2A (H2A), neutrophil elastase (ELA), myeloperoxidase (MPO), pentraxin 3 (PTX), cathepsin G (Cat-G), and cathelicidin LL37 (LL-37), at concentrations of 1, 10, and 30 µg/mL, on sperm parameters. Sperm were selected and incubated with different NET-derived proteins for 4 h. Membrane and acrosome integrity, lipoperoxidation, and membrane phospholipid disorders were also evaluated. Bovine polymorphonuclear neutrophil (PMN)/sperm co-cultures were evaluated by scanning electron microscopy and immunofluorescence. All NET-derived proteins/enzymes resulted in a reduction in membrane integrity, acrosome integrity, and lipoperoxidation at a concentration of 30 µg/mL. Bovine PMN/sperm co-cultures showed marked NET formation in the second hour. In conclusion, all NET-derived proteins/enzymes exerted cytotoxic effects on bull sperm, and this effect should be considered in future investigations on the uterine microenvironment and the advancement of spermatozoa in the FRT.

8.
Res Vet Sci ; 136: 143-150, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33626440

RESUMO

The addition of antioxidants to the cryopreservation medium has been shown to exert a positive effect on the quality of frozen-thawed sperm in different species. The objective of the present study was to evaluate the effects of supplementing the freezing medium with butylhydroxytoluene (BHT) and melatonin (MEL) in frozen-thawed pig spermatozoa. With this purpose, six ejaculates coming from six separate boars were cryopreserved in traditional freezing medium (i.e. lactose/egg-yolk/glycerol; Control) supplemented with 1.0 mM BHT (BHT-1), 2.0 mM BHT (BHT-2), 0.01 µM MEL (MEL-1) and 1.0 µM MEL (MEL-2). We evaluated sperm viability, membrane lipid disorder, acrosome integrity, mitochondrial membrane potential, lipid peroxidation, oxidation of thiol groups, and levels of total reactive oxygen species (ROS), peroxynitrite and superoxide anion (·O2-). We also analysed total (TM) and progressive sperm motilities (PM), and kinetic parameters at post-thaw (T0, T30 and T60). The BHT-2 and MEL-2 groups presented higher viability and acrosome integrity, and lower levels of peroxynitrite, ·O2- and lipid peroxidation than the control (P < 0.05), whereas MEL-2 diminished the levels of total ROS (P < 0.05). TM and PM were not affected by the treatment, while, LIN and STR shows differences between experimental groups. In conclusion, the addition of BHT and MEL to cryopreservation medium diminishes oxidative and nitrosative stress markers, which has repercussions for the integrity of plasma and acrosomal membranes of frozen-thawed spermatozoa.


Assuntos
Antioxidantes/farmacologia , Hidroxitolueno Butilado/farmacologia , Melatonina/farmacologia , Estresse Nitrosativo , Estresse Oxidativo , Espermatozoides/fisiologia , Sus scrofa/fisiologia , Animais , Masculino , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Análise do Sêmen/veterinária , Preservação do Sêmen/veterinária
9.
Bioorg Med Chem ; 18(23): 8324-33, 2010 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-21041093

RESUMO

The synthesis and in vivo anti-inflammatory activity of a series of pseudopterosin analogues are presented. Synthetic tricyclic catechol aglycons with different substitution patterns were monofucosylated or -xylosylated. Anti-inflammatory activity was conserved over a wide range of structural modifications. The most active synthetic compound 33 reduced phorbol myristate acetate (PMA)-induced inflammation in the mouse ear by 72% at 50 µg/ear. This corresponds to 80% of the activity of natural pseudopterosin A.


Assuntos
Anti-Inflamatórios/síntese química , Diterpenos/química , Galactosídeos/síntese química , Glicosídeos/química , Fenalenos/síntese química , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/uso terapêutico , Catecóis/química , Diterpenos/síntese química , Diterpenos/uso terapêutico , Galactosídeos/química , Galactosídeos/uso terapêutico , Glicosídeos/síntese química , Glicosídeos/uso terapêutico , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Camundongos , Fenalenos/química , Fenalenos/uso terapêutico , Relação Estrutura-Atividade , Acetato de Tetradecanoilforbol/toxicidade
10.
Braz J Psychiatry ; 41(2): 112-121, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30328960

RESUMO

OBJECTIVE: To identify clinical and sociodemographic factors that increase or decrease suicidal risk in a clinical sample of subjects seeking mental health care. METHOD: A cross-sectional study was performed at three health centers in Santiago, Chile. The Parental Bonding Instrument (PBI), Depressive Experience Questionnaire (DEQ), Outcome Questionnaire (OQ-45.2), Reasons for Living Inventory (RFL), and State Trait Anger Expression Inventory (STAXI-2), in addition to a sociodemographic survey, were applied to 544 participants (333 with suicidal behavior and 211 without current suicidal behavior). Through hierarchical clustering analysis, participants were grouped by similarity regarding suicidal risk. Then, a regression analysis was performed using the Least Absolute Shrinkage and Selection Operator (LASSO) technique, and factors that decrease or increase suicide risk (SR) were identified for each cluster. RESULTS: The resultant clusters were grouped mainly by the age of participants. The most important protective factor was having confidence in one's own coping skills in difficult situations. Relevant risk factors were major depressive disorder (MDD), poor anger management, and difficulties in interpersonal relationships. CONCLUSIONS: Suicidal risk manifests differently throughout the life cycle, and different types of bonds may protect from or increase risk of suicide.


Assuntos
Ideação Suicida , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise por Conglomerados , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Psicológicos , Medição de Risco , Fatores Socioeconômicos , Adulto Jovem
11.
J Org Chem ; 73(18): 7011-6, 2008 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-18710290

RESUMO

The Suzuki-Miyaura cross-coupling protocol was applied to the synthesis of 1a, the C-glycoside analogue of PsA methyl ether. This marks the first construction of a C-glycoside for this class of marine natural products, thereby offering an opportunity to compare its bioactivity to the natural substances. Its activity profile resembled that of PsA (1) and PsA O-methyl ether (1b) when assayed for its anti-inflammatory activity and its ability to inhibit phagocytosis. We conclude that the intact structure is present when a pseudopterosin expresses its anti-inflammatory and phagocytosis inhibitory properties and that they are, therefore, not likely to be prodrugs. Results show that 1a is an effective binding agent toward the A2A and A3 adenosine receptors, displaying IC50 values of 20 and 10 microM, respectively.


Assuntos
Anti-Inflamatórios/farmacologia , Diterpenos/farmacologia , Glicosídeos/síntese química , Glicosídeos/farmacologia , Éteres Metílicos/farmacologia , Tetrahymena thermophila/efeitos dos fármacos , Animais , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/química , Ligação Competitiva/efeitos dos fármacos , Linhagem Celular , Diterpenos/química , Relação Dose-Resposta a Droga , Glicosídeos/química , Humanos , Éteres Metílicos/química , Camundongos , Modelos Moleculares , Conformação Molecular , Testes de Sensibilidade Parasitária , Fagocitose/efeitos dos fármacos , Receptor A2A de Adenosina/efeitos dos fármacos , Receptor A3 de Adenosina/efeitos dos fármacos , Estereoisomerismo , Relação Estrutura-Atividade , Tetrahymena thermophila/citologia
12.
Front Psychiatry ; 8: 7, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28210230

RESUMO

AIM: In efforts to develop reliable methods to detect the likelihood of impending suicidal behaviors, we have proposed the following. OBJECTIVE: To gain a deeper understanding of the state of suicide risk by determining the combination of variables that distinguishes between groups with and without suicide risk. METHOD: A study involving 707 patients consulting for mental health issues in three health centers in Greater Santiago, Chile. Using 345 variables, an analysis was carried out with artificial intelligence tools, Cross Industry Standard Process for Data Mining processes, and decision tree techniques. The basic algorithm was top-down, and the most suitable division produced by the tree was selected by using the lowest Gini index as a criterion and by looping it until the condition of belonging to the group with suicidal behavior was fulfilled. RESULTS: Four trees distinguishing the groups were obtained, of which the elements of one were analyzed in greater detail, since this tree included both clinical and personality variables. This specific tree consists of six nodes without suicide risk and eight nodes with suicide risk (tree decision 01, accuracy 0.674, precision 0.652, recall 0.678, specificity 0.670, F measure 0.665, receiver operating characteristic (ROC) area under the curve (AUC) 73.35%; tree decision 02, accuracy 0.669, precision 0.642, recall 0.694, specificity 0.647, F measure 0.667, ROC AUC 68.91%; tree decision 03, accuracy 0.681, precision 0.675, recall 0.638, specificity 0.721, F measure, 0.656, ROC AUC 65.86%; tree decision 04, accuracy 0.714, precision 0.734, recall 0.628, specificity 0.792, F measure 0.677, ROC AUC 58.85%). CONCLUSION: This study defines the interactions among a group of variables associated with suicidal ideation and behavior. By using these variables, it may be possible to create a quick and easy-to-use tool. As such, psychotherapeutic interventions could be designed to mitigate the impact of these variables on the emotional state of individuals, thereby reducing eventual risk of suicide. Such interventions may reinforce psychological well-being, feelings of self-worth, and reasons for living, for each individual in certain groups of patients.

13.
Braz J Psychiatry ; 39(1): 1-11, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27783715

RESUMO

OBJECTIVE:: To analyze suicidal behavior and build a predictive model for suicide risk using data mining (DM) analysis. METHODS:: A study of 707 Chilean mental health patients (with and without suicide risk) was carried out across three healthcare centers in the Metropolitan Region of Santiago, Chile. Three hundred forty-three variables were studied using five questionnaires. DM and machine-learning tools were used via the support vector machine technique. RESULTS:: The model selected 22 variables that, depending on the circumstances in which they all occur, define whether a person belongs in a suicide risk zone (accuracy = 0.78, sensitivity = 0.77, and specificity = 0.79). Being in a suicide risk zone means patients are more vulnerable to suicide attempts or are thinking about suicide. The interrelationship between these variables is highly nonlinear, and it is interesting to note the particular ways in which they are configured for each case. The model shows that the variables of a suicide risk zone are related to individual unrest, personal satisfaction, and reasons for living, particularly those related to beliefs in one's own capacities and coping abilities. CONCLUSION:: These variables can be used to create an assessment tool and enables us to identify individual risk and protective factors. This may also contribute to therapeutic intervention by strengthening feelings of personal well-being and reasons for staying alive. Our results prompted the design of a new clinical tool, which is fast and easy to use and aids in evaluating the trajectory of suicide risk at a given moment.


Assuntos
Transtornos Mentais/psicologia , Prevenção do Suicídio , Adolescente , Adulto , Chile , Feminino , Humanos , Masculino , Transtornos Mentais/complicações , Pessoa de Meia-Idade , Modelos Teóricos , Fatores de Risco , Sensibilidade e Especificidade , Fatores Socioeconômicos , Inquéritos e Questionários , Adulto Jovem
14.
Braz. J. Psychiatry (São Paulo, 1999, Impr.) ; 41(2): 112-121, Mar.-Apr. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-990821

RESUMO

Objective: To identify clinical and sociodemographic factors that increase or decrease suicidal risk in a clinical sample of subjects seeking mental health care. Method: A cross-sectional study was performed at three health centers in Santiago, Chile. The Parental Bonding Instrument (PBI), Depressive Experience Questionnaire (DEQ), Outcome Questionnaire (OQ-45.2), Reasons for Living Inventory (RFL), and State Trait Anger Expression Inventory (STAXI-2), in addition to a sociodemographic survey, were applied to 544 participants (333 with suicidal behavior and 211 without current suicidal behavior). Through hierarchical clustering analysis, participants were grouped by similarity regarding suicidal risk. Then, a regression analysis was performed using the Least Absolute Shrinkage and Selection Operator (LASSO) technique, and factors that decrease or increase suicide risk (SR) were identified for each cluster. Results: The resultant clusters were grouped mainly by the age of participants. The most important protective factor was having confidence in one's own coping skills in difficult situations. Relevant risk factors were major depressive disorder (MDD), poor anger management, and difficulties in interpersonal relationships. Conclusions: Suicidal risk manifests differently throughout the life cycle, and different types of bonds may protect from or increase risk of suicide.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Adulto Jovem , Ideação Suicida , Fatores Socioeconômicos , Análise por Conglomerados , Estudos Transversais , Medição de Risco , Pessoa de Meia-Idade , Modelos Psicológicos
15.
Braz. J. Psychiatry (São Paulo, 1999, Impr.) ; 39(1): 1-11, Jan.-Mar. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-844179

RESUMO

Objective: To analyze suicidal behavior and build a predictive model for suicide risk using data mining (DM) analysis. Methods: A study of 707 Chilean mental health patients (with and without suicide risk) was carried out across three healthcare centers in the Metropolitan Region of Santiago, Chile. Three hundred forty-three variables were studied using five questionnaires. DM and machine-learning tools were used via the support vector machine technique. Results: The model selected 22 variables that, depending on the circumstances in which they all occur, define whether a person belongs in a suicide risk zone (accuracy = 0.78, sensitivity = 0.77, and specificity = 0.79). Being in a suicide risk zone means patients are more vulnerable to suicide attempts or are thinking about suicide. The interrelationship between these variables is highly nonlinear, and it is interesting to note the particular ways in which they are configured for each case. The model shows that the variables of a suicide risk zone are related to individual unrest, personal satisfaction, and reasons for living, particularly those related to beliefs in one’s own capacities and coping abilities. Conclusion: These variables can be used to create an assessment tool and enables us to identify individual risk and protective factors. This may also contribute to therapeutic intervention by strengthening feelings of personal well-being and reasons for staying alive. Our results prompted the design of a new clinical tool, which is fast and easy to use and aids in evaluating the trajectory of suicide risk at a given moment.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Suicídio/prevenção & controle , Transtornos Mentais/psicologia , Fatores Socioeconômicos , Chile , Inquéritos e Questionários , Fatores de Risco , Sensibilidade e Especificidade , Transtornos Mentais/complicações , Modelos Teóricos
16.
Comp Biochem Physiol C Toxicol Pharmacol ; 143(4): 436-43, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16759914

RESUMO

The free living ciliate Tetrahymena thermophila was chosen as a cellular model in order to investigate the mode of action of the anti-inflammatory marine natural product Pseudopterosin A (PsA). In this paper we present evidence that PsA inhibits phagosome formation (KD=10.5 microM) and triggers a discrete intracellular calcium release (depletion) from a site in T. thermophila cells (KD=6.4 microM). Pre-treatment with the Gi/o protein inhibitor, pertussis toxin (PTX), inhibits PsA activity of both responses providing pharmacological evidence that the site of action for PsA is at a PTX sensitive G protein or a G protein coupled receptor (GPCR). Addition of extracellular calcium induced a concentration dependent increase in the incidence of phagosome formation (KD=30.3 microM) and was blocked by PsA pre-treatment. This particular effect of PsA on extracellular calcium was not blocked by PTX pre-treatment.


Assuntos
Cálcio/metabolismo , Diterpenos/farmacologia , Glicosídeos/farmacologia , Toxina Pertussis/farmacologia , Fagocitose/efeitos dos fármacos , Animais , Cloreto de Cálcio/farmacologia , Diterpenos/antagonistas & inibidores , Estrenos/farmacologia , Proteínas de Ligação ao GTP/fisiologia , Glicosídeos/antagonistas & inibidores , Fagossomos/efeitos dos fármacos , Fagossomos/fisiologia , Pirrolidinonas/farmacologia , Tetrahymena thermophila/efeitos dos fármacos
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