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1.
Arch Med Res ; 55(2): 102960, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38290199

RESUMO

BACKGROUND: SARS-CoV2 induces flu-like symptoms that can rapidly progress to severe acute lung injury and even death. The virus also invades the central nervous system (CNS), causing neuroinflammation and death from central failure. Intravenous (IV) or oral dexamethasone (DXM) reduced 28 d mortality in patients who required supplemental oxygen compared to those who received conventional care alone. Through these routes, DMX fails to reach therapeutic levels in the CNS. In contrast, the intranasal (IN) route produces therapeutic levels of DXM in the CNS, even at low doses, with similar systemic bioavailability. AIMS: To compare IN vs. IV DXM treatment in hospitalized patients with COVID-19. METHODS: A controlled, multicenter, open-label trial. Patients with COVID-19 (69) were randomly assigned to receive IN-DXM (0.12 mg/kg for three days, followed by 0.6 mg/kg for up to seven days) or IV-DXM (6 mg/d for 10 d). The primary outcome was clinical improvement, as defined by the National Early Warning Score (NEWS) ordinal scale. The secondary outcome was death at 28 d between IV and IN patients. Effects of both treatments on biochemical and immunoinflammatory profiles were also recorded. RESULTS: Initially, no significant differences in clinical severity, biometrics, and immunoinflammatory parameters were found between both groups. The NEWS-2 score was reduced, in 23 IN-DXM treated patients, with no significant variations in the 46 IV-DXM treated ones. Ten IV-DXM-treated patients and only one IN-DXM patient died. CONCLUSIONS: IN-DMX reduced NEWS-2 and mortality more efficiently than IV-DXM, suggesting that IN is a more efficient route of DXM administration.


Assuntos
COVID-19 , Humanos , SARS-CoV-2 , RNA Viral , Tratamento Farmacológico da COVID-19 , Dexametasona/uso terapêutico
2.
Tuberculosis (Edinb) ; 138: 102274, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36463716

RESUMO

INTRODUCTION: Tuberculosis (TB) caused by Mycobacterium tuberculosis mainly affects the lungs, but can spread to other organs. TB chronically activates the immune and endocrine systems producing remarkable functional changes.So far, it is unknown whether pulmonary non-disseminated TB cause changes in the female reproductive system and lung endocrinology. OBJECTIVE: To investigate whether pulmonary TB produces immunoendocrine alterations of the female mice reproductive organs, and lung estradiol synthesis. METHODS: BALB/c mice were infected intratracheally with Mycobacterium tuberculosis (Mtb) strain H37Rv. Groups of six non-infected and infected animals were euthanized on different days. Bacillary loads were determined in the lungs, ovaries and uterus. Immunohistochemistry and morphometry studies were performed in histological sections. Serum estradiol wasassayed, and supernatantfrom cultured lung cells was analyzed by Thin Layer Chromatography (TLC). RESULTS: Mtb only grew in lung tissue. Histopathology revealed abnormal folliculogenesis and decreased corpora lutea. Altered ovarian expression of IL-6, IL-1ß was found. The infection increased serum estradiol. Estradiol synthesis by infected lung cells triplicate after 30 pi days.Aromatase immunostaining was found in the alveolar and bronchial epithelium, being stronger in the infected lungs, mainly in macrophages. CONCLUSION: Pulmonary TB affects the histophysiology of the female reproductive system in absence of its local infection, and disturbslung endocrinology.


Assuntos
Mycobacterium tuberculosis , Tuberculose Pulmonar , Feminino , Animais , Camundongos , Tuberculose Pulmonar/microbiologia , Pulmão/microbiologia , Macrófagos/patologia , Genitália Feminina/patologia
3.
J Exp Biol ; 223(Pt 24)2020 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-33161382

RESUMO

One of the most common tools in conservation physiology is the assessment of environmental stress via glucocorticoid measurement. However, little is known of its relationship with other stress-related biomarkers, and how the incidence of an immune challenge during long-term stress could affect an individual's overall stress response. We investigated here the relationship between basal and post-acute stress fecal cortisol metabolite (FC) with different antioxidant enzymes, oxidative damage and immune parameters in the fish-eating bat, Myotis vivesi We found that in both basal and post-stress conditions, FC was highly related with a number of antioxidant enzymes and immune parameters, but not to oxidative damage. We also assessed changes of FC through the seasons. Basal FC samples and stress reactivity after short-duration stress displayed similar levels during summer, autumn and early winter, but lower concentrations in late winter. Stress reactivity after long-duration stress was greater in summer and early winter. Finally, we tested the effect of a simultaneous exposure to a long, strong stress stimulus with an immune response stimulation by administrating adrenocorticotropic hormone (ACTH) and phytohemagglutinin (PHA) after 42 h. Results showed that when both stimuli were administrated, FC concentrations, inflammation and some antioxidant activity were lowered in comparison with the control and individual administration of the challenges. Our findings support the idea that animals maintain constant basal glucocorticoid levels when living in challenging environments, but response to acute stress differs seasonally and immune defense mechanisms and stress responses might be compromised when confronted with multiple challenges.


Assuntos
Quirópteros , Hidrocortisona , Hormônio Adrenocorticotrópico , Animais , Antioxidantes , Estresse Oxidativo
4.
Steroids ; 155: 108556, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31866547

RESUMO

Glioblastoma (GBM) is the most aggressive local brain tumor and effective treatments are lacking. Many studies have proposed an important participation of steroid hormones in the development of gliomas. Evidence was provided by statistics analysis where the incidence in adult population is 50% higher in men than in women. Female patients have a better prognosis for survival compared to male patients with GBM. Also, the expression of receptors to estrogen, progesterone and androgens in glioma cell lines and tumor biopsies, and glucocorticoid receptors in GBM cell lines had been reported. Here we have investigated the effect of the pharmacological inhibition of 5-α reductases on the capacity of GBM derived cell lines C6 (rat) and U87 (human) to synthesize neurosteroids. As the knowledge of the pathways used to synthesize neurosteroids by GBM derived cells was incomplete, we have investigated the synthesis of these steroids by C6 and U87 cells using tritiated precursors and thin layer chromatography (TLC). Increasing concentrations of finasteride and dutasteride were added to U87 culture media that was collected after 24 and 48 h. The results of the study showed that C6 cells incubated with 3H-cholesterol yielded dihydroandrosterone, hydroxytestosterone, androstenediol, androstenedione and estriol, while U87 cells also synthesized progesterone, and androstanedione. Incubation with 3H-androstenedione or 3H-testosterone mainly yielded dihydrotestosterone, androsterone, dihydroandrosterone, hydroxytestosterone, and estradiol in both lines. To note, we showed here for the first time that U87 cells synthesize corticosteroids. Addition of finasteride or dutasteride to U87 cells reduced androgen and estrogen synthesis. Dutasteride also decreased the synthesis of dihydrocorticosterone and allotetrahydrodesoxycorticosterone while deoxycorticosterone was accumulated. In summary, both GBM cell lines synthesize numerous neurosteroids, including 5-α reductase products and 3α-HSD pathways that were inhibited by finasteride and dutasteride. These inhibitors may be considered as tools to control neurosteroid synthesis of potential relevance for GBM survival.


Assuntos
Dutasterida/farmacologia , Finasterida/farmacologia , Glioblastoma/tratamento farmacológico , Neuroesteroides/antagonistas & inibidores , Animais , Relação Dose-Resposta a Droga , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Neuroesteroides/química , Neuroesteroides/metabolismo , Ratos , Células Tumorais Cultivadas
5.
Tuberculosis (Edinb) ; 109: 109-116, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29559114

RESUMO

INTRODUCTION: Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis (Mtb) that mainly affects the lungs. Along the course of pulmonary TB there are remarkable changes in the production of cytokines that cause endocrine changes. So far, it is not known the physiological and histological changes in the male reproductive system during pulmonary TB. OBJECTIVE: To investigate whether pulmonary TB produces histological alterations of the BALB/c mice reproductive organs, as well as abnormalities in spermatogenesis, serum testosterone concentrations and expression of testicular cytokines. METHODS: BALB/c mice were infected intratracheally with high dose Mtb strain H37Rv. Groups of six non infected and infected animals were euthanized on days 1, 3, 7, 14, 21, 28, 60, 90 and 120 post-infection. Bacillary loads were determined by counting colony forming units (CFUs) in lungs, testes, prostate and seminal vesicles. Histological sections were obtained from the same organs. Spermatozoids number and quality were assessed by spermatobioscopy. Serum testosterone concentrations were determined by radioimmunoanalysis (RIA) in control and infected mice in each time of sacrifice. RESULTS: Mtb only grew in lung tissue. Serum androgens showed a trend to decrease in the infected mice compared to the healthy animals, the difference turn into statistically significance at post infection day 120. The weight of the testis was not modified throughout the study, and no histopathological changes were found. However, we detected a significant decrease in the weight of the seminal vesicles and prostate starting at 28 days post-infection. Atrophy of the seminal vesicles and prostate epithelia were significant, beginning after 60 days of infection. Spermatobioscopy revealed hypospermia in the later stages of the disease. We have observed in the testes a local significant disbalance on the cytokine profile (increase of IL-6 and decrease of IL-10 and TGF-b levels) together with a very significant reduction of the body weight during late pulmonary TB. CONCLUSION: Pulmonary TB affects the histophysiology of the male reproductive system due to hormonal changes, an imbalance of pro-inflammatory cytokine profile, and a wasting syndrome during late disease.


Assuntos
Citocinas/metabolismo , Genitália Masculina/metabolismo , Pulmão/microbiologia , Mycobacterium tuberculosis/patogenicidade , Testosterona/sangue , Tuberculose Pulmonar/microbiologia , Animais , Carga Bacteriana , Citocinas/imunologia , Modelos Animais de Doenças , Genitália Masculina/imunologia , Genitália Masculina/patologia , Interações Hospedeiro-Parasita , Masculino , Camundongos Endogâmicos BALB C , Mycobacterium tuberculosis/crescimento & desenvolvimento , Espermatogênese , Espermatozoides/imunologia , Espermatozoides/metabolismo , Fatores de Tempo , Tuberculose Pulmonar/sangue , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/patologia
6.
PLoS One ; 11(2): e0149671, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26901767

RESUMO

The rapid loss, fragmentation and degradation of tropical forests threaten the survival of many animal species. However, the way in which these phenomena affect animal health has been poorly explored, thus limiting the design of appropriate conservation strategies. To address this, here we identified using linear mixed models the effect of proximal (diet, activity pattern, hunting and logging) and distal (sum of the basal areas of fruiting-tree species [SBAFS], landscape forest cover and degree of forest fragmentation) variables over fecal glucocorticoid metabolite (fGCM) levels-hormones associated with animal health and fitness-of six groups of spider monkeys (Ateles geoffroyi) inhabiting six landscapes with different spatial structures in Mexico. Proximal variables showed a stronger predictive power over fGCMs than distal. In this sense, increases in travel time, the occurrence of hunting, and reductions in rest time and fruit consumption resulted in higher fGCM levels. Regarding distal variables, increases in SBAFS were negatively related to fGCM levels, thus suggesting that food scarcity increases stress hormone levels. Nevertheless, contrary to theoretical expectations, spider monkeys living in smaller tracts of forest spent less time travelling, but the same time feeding on fruit as those in more forested areas. The lower net energy return associated with this combination of factors would explain why, contrary to theoretical expectations, increased forest cover was associated with increased levels of fGCMs in these groups. Our study shows that, at least in the short term, spider monkeys in fragmented landscapes do not always present higher levels of stress hormones compared to those inhabiting continuous forest, and the importance of preserving fruit sources and controlling hunting for reducing the levels of stress hormones in free ranging spider monkeys.


Assuntos
Ecossistema , Meio Ambiente , Comportamento Predatório , Primatas , Animais , México
7.
Front Neurosci ; 9: 224, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26175665

RESUMO

In many cases parasites display highly complex life cycles that include the penetration and permanence of the larva or adults within host organs, but even in those that only have one host, reciprocal, intricate interactions occur. Evidence indicates that steroid hormones have an influence on the development and course of parasitic infections. The host gender's susceptibility to infection, and the related differences in the immune response are good examples of the host-parasite interplay. However, the capacity of these organisms to synthesize their own steroidogenic hormones still has more questions than answers. It is now well-known that many parasites synthesize ecdysteroids, but limited information is available on sex steroid and corticosteroid synthesis. This review intends to summarize some of the existing information in the field. In most, but not all parasitosis the host's hormonal environment determines the susceptibility, the course, and severity of parasite infections. In most cases the infection disturbs the host environment, and activates immune responses that end up affecting the endocrine system. Furthermore, sex steroids and corticosteroids may also directly modify the parasite reproduction and molting. Available information indicates that parasites synthesize some steroid hormones, such as ecdysteroids and sex steroids, and the presence and activity of related enzymes have been demonstrated. More recently, the synthesis of corticosteroid-like compounds has been shown in Taenia solium cysticerci and tapeworms, and in Taenia crassiceps WFU cysticerci. In-depth knowledge of the parasite's endocrine properties will contribute to understand their reproduction and reciprocal interactions with the host, and may also help designing tools to combat the infection in some clinical situations.

8.
Can J Microbiol ; 61(7): 451-5, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25994226

RESUMO

Fast-growing mycobacteria such as Mycobacterium sp. and Mycobacterium smegmatis degrade natural sterols. They are a model to study tuberculosis. Interestingly, M. smegmatis has been found in river effluents derived from paper production, and therefore, it would be important to gain further insight into its capacity to synthesize steroids that are potential endocrine disruptors affecting the development and reproduction of fishes. To our knowledge, the capacity of M. smegmatis to synthesize estrogens and even testosterone has not been previously reported. Therefore, the objective of this study was to investigate the capacity of M. smegmatis to synthesize in vitro testosterone and estrogens from tritiated precursors and to investigate the metabolic pathways involved. Results obtained by thin-layer chromatography showed that (3)H-progesterone was transformed to 17OH-progesterone, androstenedione, testosterone, estrone, and estradiol after 6, 12, or 24 h of incubation. (3)H-androstenedione was transformed into testosterone and estrogens, mainly estrone, and (3)H-testosterone was transformed to estrone and androstenedione. Incubation with (3)H-dehydroepiandrosterone rendered androstenediol, testosterone, and estrogens. This ability to transform less potent sex steroids like androstenedione and estrone into other more active steroids like testosterone and estradiol or vice versa suggests that M. smegmatis can influence the amount of self-synthesized strong androgens and estrogens and can transform those found in the environment.


Assuntos
Androgênios/metabolismo , Estrogênios/metabolismo , Mycobacterium smegmatis/metabolismo , Esteroides/metabolismo , Androgênios/análise , Cromatografia em Camada Fina , Desidroepiandrosterona , Estrogênios/análise , Feminino , Humanos , Mycobacterium smegmatis/química , Esteroides/análise
9.
Neuroimmunomodulation ; 17(3): 209-12, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20134205

RESUMO

Depression and stress are related pathologies extensively studied in humans. However, this relationship is not well known in animals kept in zoos and even less known in wild animals. In zoo animals, acute and chronic stress caused by difficulties in coping with stressors such as public presence and noise, among others, can induce the appearance of repetitive pathological behaviors such as stereotypies, many times associated with organic pathologies that deeply affect their health and welfare. In the wild, factors such as deforestation, habitat fragmentation, lack of food and water, and human disturbances are potential causes of acute and chronic stress for the resident fauna. Glucocorticoids (GC) have been extensively used as stress indicators in many species including humans. Since chase and handling of wild animals immediately raise their GC serum levels, noninvasive methods have been developed to assess stress without interference caused by sample collection. The hormones and their metabolites can be measured in various body fluids and excreta and detect basal feedback free hormone concentrations as well as the response to ACTH and handling. In order to study the influence of disturbing factors we have measured GC as stress indicators by noninvasive techniques in dolphins and felids (ocelots, jaguarundis and margays) and cortisol and testosterone in spider monkeys.


Assuntos
Animais Selvagens/metabolismo , Animais de Zoológico/metabolismo , Glucocorticoides/análise , Glucocorticoides/metabolismo , Estresse Psicológico/diagnóstico , Estresse Psicológico/metabolismo , Animais , Animais Selvagens/imunologia , Animais de Zoológico/imunologia , Cetáceos/imunologia , Cetáceos/metabolismo , Transtorno Depressivo/metabolismo , Transtorno Depressivo/fisiopatologia , Ecossistema , Meio Ambiente , Fezes/química , Felidae/imunologia , Felidae/metabolismo , Abrigo para Animais , Primatas/imunologia , Primatas/metabolismo , Radioimunoensaio/métodos , Comportamento Social , Estresse Psicológico/fisiopatologia , Testosterona/análise , Testosterona/metabolismo
10.
Parasitol Res ; 103(4): 847-52, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18626663

RESUMO

Larval and adult stages of Taenia solium and Taenia crassiceps WFU strain were analyzed by histochemical and biochemical methods to determine the existence of steroid pathways. The presence of the key enzyme 3beta-hydroxisteroid-dehydrogenase (3beta-HSD) was examined in frozen sections of cysticerci obtained from mice and segments of tapeworms obtained from the intestine of hamsters. 3beta-HSD activity was detected by nitroblue-tetrazolium products after incubation with dehydroepiandrosterone, androstendiol, or pregnenolone. Tapeworm tissues exhibited 3beta-HSD activity in the subtegumentary areas of the neck and immature proglottids following incubation with androstendiol, as well as surrounding the testes in mature proglottids. T. solium cysticerci exhibited 3beta-HSD activity in the subtegumentary tissues. The synthesis of steroid hormones involving the activity of 3beta-HSD was studied in cysticerci or tapeworms incubated in the presence of tritiated steroid precursors. The culture media were analyzed by thin layer chromatography and showed synthesis of androstendiol, testosterone, and 17beta-estradiol by cysticerci, androstendiol, and 17beta-estradiol by tapeworms. The results strongly suggest the activity of 3beta-HSD in taeniid parasites that have at least a part of the enzymatic chain required for androgen and estrogen synthesis and that the enzymes are present in the larval stage and from the early strobilar stages to the mature proglottids.


Assuntos
3-Hidroxiesteroide Desidrogenases/metabolismo , Cysticercus/enzimologia , Taenia/enzimologia , Androstenodiol/metabolismo , Animais , Cromatografia em Camada Fina , Cricetinae , Meios de Cultura/química , Cysticercus/crescimento & desenvolvimento , Desidroepiandrosterona/metabolismo , Estradiol/análise , Intestinos/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Nitroazul de Tetrazólio/metabolismo , Pregnenolona/metabolismo , Coloração e Rotulagem , Taenia/crescimento & desenvolvimento , Testosterona/análise
11.
Curr Top Med Chem ; 8(5): 408-18, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18393904

RESUMO

Over the last years the biology of many parasites that infect humans and domestic animals has been intensively studied. Considerable efforts were addressed to obtain information on the parasite-host immune relationship. However, the knowledge of the endocrine physiology of parasites and the consequences of the local hormone production on the host tissues needs further investigation. We review here literature and our own studies on endocrine parasite capacities with special emphasis on cysticercosis. Besides the biological interest, these investigations may contribute to identify in the future alternative treatments for the disease.


Assuntos
Anti-Helmínticos/farmacologia , Desenho de Fármacos , Hormônios Esteroides Gonadais/metabolismo , Animais , Anti-Helmínticos/química , Humanos
12.
J Appl Anim Welf Sci ; 7(3): 171-9, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15498724

RESUMO

Environmental enrichment can be a useful tool to reduce belly nosing behaviors in early weaned piglets. The aim of this study was to assess the effect of environmental enrichment on behavior, salivary cortisol, and productivity of piglets weaned at 14 days of age. The study assigned 112 piglets (line Camborough 22 of PIC) into 2 treatments, control and enriched, and observed them for 192 hr in 3 periods: 14 to 28 days of age (Phase 1), 28 to 42 days of age (Phase 2), and 42 to 54 days of age (Phase 3). The study obtained saliva samples in each phase from 56 piglets selected randomly from each group for cortisol determination. Comparisons between both treatments and phases included the following: proportion of time belly nosing, latency of approaching a person, average levels of salivary cortisol, and daily weight gain. Belly nosing was higher and latency of approaching a person lower in the control group than in the enriched one (p < .05 and p < .01). Belly nosing was lower in Phase 3 (p < .05); latency of approaching a person was higher in Phase 1 with respect to Phase 2, and this was higher with respect to Phase 3 (p < .01). There were no differences in salivary cortisol levels between treatments or phases. Weight gain was higher in the enriched group (p < .001). Environmental enrichment in piglets weaned at 14 days of age resulted in a reduced proportion of time nosing, reduced latency of response to humans, and better growth than piglets in barren environments.


Assuntos
Criação de Animais Domésticos , Animais Lactentes/crescimento & desenvolvimento , Animais Lactentes/psicologia , Comportamento Animal , Hidrocortisona/análise , Saliva/metabolismo , Desmame , Animais , Animais Lactentes/metabolismo , Feminino , Masculino , Suínos , Fatores de Tempo , Aumento de Peso
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