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1.
Neuropharmacology ; 246: 109832, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38176535

RESUMO

Memory reconsolidation is a process by which labile drug memories are restabilized in long-term memory stores, permitting their enduring control over drug-seeking behaviors. In the present study, we investigated the involvement of the dorsal raphé nuclei (DRN) in cocaine-memory reconsolidation. Sprague-Dawley rats (male, female) were trained to self-administer cocaine in a distinct environmental context to establish contextual drug memories. They then received extinction training in a different context. Next, the rats were re-exposed to the cocaine-predictive context for 15 min to reactivate their cocaine memories or remained in their home cages (no-reactivation control). Memory reactivation was sufficient to increase c-Fos expression, an index of neuronal activation, in the DRN, but not in the median raphé nuclei, during reconsolidation, compared to no reactivation. To determine whether DRN neuronal activity was necessary for cocaine-memory reconsolidation, rats received intra-DRN baclofen plus muscimol (BM; GABAB/A agonists) or vehicle microinfusions immediately after or 6 h after a memory reactivation session conducted with or without lever access. The effects of DRN functional inactivation on long-term memory strength, as indicated by the magnitude of context-induced cocaine seeking, were assessed 72 h later. Intra-DRN BM treatment immediately after memory reactivation with or without lever access attenuated subsequent context-induced cocaine-seeking behavior, independent of sex. Conversely, BM treatment in the adjacent periaqueductal gray (PAG) immediately after memory reactivation, or BM treatment in the DRN 6 h after memory reactivation, did not alter responding. Together, these findings indicate that the DRN plays a requisite role in maintaining cocaine-memory strength during reconsolidation.


Assuntos
Cocaína , Núcleo Dorsal da Rafe , Feminino , Ratos , Masculino , Animais , Ratos Sprague-Dawley , Memória , Extinção Psicológica , Cocaína/farmacologia
3.
Obesity (Silver Spring) ; 29(12): 1978-1981, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34813174

RESUMO

The North American Association for the Study of Obesity (NAASO), the precursor of The Obesity Society (TOS), was founded in 1981 and turns 40 years old in 2021. The Society was organized by George Bray along with John Brunzell, C. Wayne Callaway, M.R.C. Greenwood, and Judith Stern. It held its foundational meeting with a theme of "Types of Obesity: Animal Models and Clinical Applications" at Vassar College in the fall of 1982 along with symposia and an NIH workshop titled "Methods of Characterizing Human Obesity." At a follow-up meeting during the Fourth International Congress on Obesity, Barbara Hansen was elected President, Judith Stern Secretary, and Anne Sullivan Treasurer. Incorporation of NAASO occurred in 1984.


Assuntos
Obesidade , Animais , Escolaridade , História do Século XX
5.
ACS Infect Dis ; 7(5): 1275-1282, 2021 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-33740373

RESUMO

New drugs are critically needed to treat Cryptosporidium infections, particularly for malnourished children under 2 years old in the developing world and persons with immunodeficiencies. Bioactive compounds from the Tres-Cantos GSK library that have activity against other pathogens were screened for possible repurposing against Cryptosporidium parvum growth. Nineteen compounds grouped into nine structural clusters were identified using an iterative process to remove excessively toxic compounds and screen related compounds from the Tres-Cantos GSK library. Representatives of four different clusters were advanced to a mouse model of C. parvum infection, but only one compound, an imidazole-pyrimidine, led to significant clearance of infection. This imidazole-pyrimidine compound had a number of favorable safety and pharmacokinetic properties and was maximally active in the mouse model down to 30 mg/kg given daily. Though the mechanism of action against C. parvum was not definitively established, this imidazole-pyrimidine compound inhibits the known C. parvum drug target, calcium-dependent protein kinase 1, with a 50% inhibitory concentration of 2 nM. This compound, and related imidazole-pyrimidine molecules, should be further examined as potential leads for Cryptosporidium therapeutics.


Assuntos
Doenças Transmissíveis , Criptosporidiose , Cryptosporidium parvum , Cryptosporidium , Criptosporidiose/tratamento farmacológico , Reposicionamento de Medicamentos , Humanos , Lactente
6.
Anim Genet ; 51(5): 752-762, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32524667

RESUMO

The black soldier fly, Hermetia illucens, is an emerging biotechnological agent with its larvae being effective converters of organic waste into usable bio-products including protein and lipids. To date, most operations use unimproved commercial populations produced by mass rearing, without cognisance of specific breeding strategies. The genetic and phenotypic consequences of these commercial practices remain unknown and could have a significant impact on long-term population viability and productivity. The aim of this study was thus to assess the genetic and phenotypic changes during the early phases of colony establishment and domestication in the black soldier fly. An experimental colony was established from wild founder flies and a new microsatellite marker panel was developed to assess population genetic parameters along with the phenotypic characteristics of each generational cohort under captive breeding. The experimental colony was characterised by a small effective population size, subsequent loss of genetic diversity and rapid genetic and phenotypic differentiation between the generational cohorts. Ultimately, the population collapsed by the fifth generation, most likely owing to the adverse effect of inbreeding depression following the fixation of deleterious alleles. Species with r-selected life history characteristics (e.g. short life-span, high fecundity and low larval survival) are known to pose particular challenges for genetic management. The current study suggests that sufficient genetic and phenotypic variations exist in the wild population and that domestication and strain development could be achieved with careful population augmentation and selection during the early stages of colony establishment.


Assuntos
Dípteros/genética , Domesticação , Variação Genética , Animais , Dípteros/crescimento & desenvolvimento , Larva/genética , Larva/crescimento & desenvolvimento , Fenótipo
8.
Osteoarthritis Cartilage ; 27(8): 1174-1184, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31028882

RESUMO

OBJECTIVE: Osteoarthritis (OA) is a multifactorial disease with etiological heterogeneity. The objective of this study was to classify OA subgroups by generating metabolomic phenotypes from human synovial fluid. DESIGN: Post mortem synovial fluids (n = 75) were analyzed by high performance-liquid chromatography mass spectrometry (LC-MS) to measure changes in the global metabolome. Comparisons of healthy (grade 0), early OA (grades I-II), and late OA (grades III-IV) donor populations were considered to reveal phenotypes throughout disease progression. RESULTS: Global metabolomic profiles in synovial fluid were distinct between healthy, early OA, and late OA donors. Pathways differentially activated among these groups included structural deterioration, glycerophospholipid metabolism, inflammation, central energy metabolism, oxidative stress, and vitamin metabolism. Within disease states (early and late OA), subgroups of donors revealed distinct phenotypes. Synovial fluid metabolomic phenotypes exhibited increased inflammation (early and late OA), oxidative stress (late OA), or structural deterioration (early and late OA) in the synovial fluid. CONCLUSION: These results revealed distinct metabolic phenotypes in human synovial fluid, provide insight into pathogenesis, represent novel biomarkers, and can move toward developing personalized interventions for subgroups of OA patients.


Assuntos
Cartilagem Articular/metabolismo , Metabolômica , Osteoartrite do Joelho/metabolismo , Líquido Sinovial/metabolismo , Adulto , Idoso , Biomarcadores/metabolismo , Cromatografia Líquida , Progressão da Doença , Regulação para Baixo , Humanos , Inflamação/metabolismo , Espectrometria de Massas , Pessoa de Meia-Idade , Osteoartrite do Joelho/classificação , Estresse Oxidativo , Fenótipo , Índice de Gravidade de Doença , Regulação para Cima , Adulto Jovem
9.
Aust Dent J ; 2018 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-29878377

RESUMO

BACKGROUND: Oral and dental disease is a major cause of long-term morbidity following allogeneic blood and marrow transplantation (Allo-BMT). This study aimed to describe the extent and range of oral and dental complications in BMT recipients and to identify gaps in service provision provided to this high-risk group. METHODS: Participants were Allo-BMT recipients, aged >18 years, and received transplants between 2000 and 2012 in NSW. They completed seven surveys, the purpose-designed Sydney Post-BMT Study survey and six other validated instruments. RESULTS: Of 441 respondents, many reported dry mouth (45.1%), dental caries (36.7%), mouth ulcers (35.3%), oral GVHD (35.1%), gingivitis (16.2%), tooth abscess (6.1%) and oral cancer (1.5%). Regular dental visits were reported by 66.2% of survivors. Middle-high income, older age and geographic location showed a positive association with regular dental visits. Of those who did not visit the dentist regularly, 37% stated they did not feel it necessary, 36% reported cost and 20% stated it was not advised by the treating team. CONCLUSION: Despite oral complications commonly occurring after Allo-BMT, many survivors receive inadequate dental care. These results emphasize the need for improved oral health education, the importance of regular dental checks and improvement in the delivery of dental health services for BMT survivors.

10.
Obes Rev ; 19(9): 1205-1235, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29761610

RESUMO

Calories from any food have the potential to increase risk for obesity and cardiometabolic disease because all calories can directly contribute to positive energy balance and fat gain. However, various dietary components or patterns may promote obesity and cardiometabolic disease by additional mechanisms that are not mediated solely by caloric content. Researchers explored this topic at the 2017 CrossFit Foundation Academic Conference 'Diet and Cardiometabolic Health - Beyond Calories', and this paper summarizes the presentations and follow-up discussions. Regarding the health effects of dietary fat, sugar and non-nutritive sweeteners, it is concluded that food-specific saturated fatty acids and sugar-sweetened beverages promote cardiometabolic diseases by mechanisms that are additional to their contribution of calories to positive energy balance and that aspartame does not promote weight gain. The challenges involved in conducting and interpreting clinical nutritional research, which preclude more extensive conclusions, are detailed. Emerging research is presented exploring the possibility that responses to certain dietary components/patterns are influenced by the metabolic status, developmental period or genotype of the individual; by the responsiveness of brain regions associated with reward to food cues; or by the microbiome. More research regarding these potential 'beyond calories' mechanisms may lead to new strategies for attenuating the obesity crisis.


Assuntos
Doenças Cardiovasculares/complicações , Dieta , Doenças Metabólicas/complicações , Doenças Cardiovasculares/metabolismo , Ingestão de Energia/fisiologia , Humanos , Doenças Metabólicas/metabolismo , Valor Nutritivo , Aumento de Peso/fisiologia
11.
Eur J Dent Educ ; 22(3): e588-e593, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29667358

RESUMO

In March 2017, a group of teachers of human disease/clinical medical science (HD/CMSD) representing the majority of schools from around the UK and Republic of Ireland met to discuss the current state of teaching of human disease and also to discuss how the delivery of this theme might evolve to inform improved healthcare. This study outlines how the original teaching in medicine and surgery to dental undergraduate students has developed into the theme of HD/CMSD reflecting changing needs as well as guidance from the regulators, and how different dental schools have developed their approaches to reach their current state. Each school was also asked to share a strengths, weakness, opportunities and threats (SWOT) analysis of their programme and to outline how they thought their HD/CMSD programme may develop. The school representatives who coordinate the delivery and assessment of HD/CMSD in the undergraduate curriculum have extensive insight in this area and are well-placed to shape the HD/CMSD development for the future.


Assuntos
Medicina Clínica/tendências , Currículo/tendências , Educação em Odontologia/tendências , Educação de Graduação em Medicina/tendências , Faculdades de Odontologia/tendências , Estudantes de Odontologia , Docentes de Odontologia , Humanos , Irlanda , Reino Unido
13.
Bone Marrow Transplant ; 51(10): 1361-1368, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27214081

RESUMO

Allogeneic haematopoietic stem cell transplantation (allo-HSCT) entails long-term morbidities that impair survivors' quality of life through broad physical and psychosocial sequelae. Current data and survival measurements may be inadequate for contemporary Australian allo-HSCT recipients. This study sought to comprehensively describe survivorship in an up-to-date, local setting through validated measurements and a novel questionnaire designed to complement and address limitations of current instruments. All adults who received an allo-HSCT between 2000 and 2012 in New South Wales were eligible and included, if alive, those literate and consenting to the study, which encompassed seven survey instruments. Four hundred and forty-three survivors participated, which is 76% of contactable (n=583) and 66% of eligible survivors (n= 669). Chronic GVHD (cGVHD) and co-morbidity rates were similar to published data. Noteworthy results include prevalent sexual dysfunction (66% females, 52% males), loss of income (low income increased from 21 to 36%, P<0.001) and employment (full-time employment fell from 64 to 33%, P<0.001), suboptimal vaccination (31% complete), and health screening (≈50%). Risk factors for poor vaccination and health screening were cGVHD, younger age, less education, rural/regional residence and transplantation <2 years. This study suggests that improvement in survivorship may necessitate structural changes in the current delivery of health services.


Assuntos
Transplante de Células-Tronco Hematopoéticas/psicologia , Qualidade de Vida , Sobreviventes/psicologia , Adulto , Idoso , Atenção à Saúde/normas , Feminino , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , New South Wales , Inquéritos e Questionários , Transplante Homólogo , Adulto Jovem
14.
J Neuroendocrinol ; 28(4)2016 04.
Artigo em Inglês | MEDLINE | ID: mdl-26833868

RESUMO

The synthesis of arginine vasopressin (AVP) in the supraoptic nucleus (SON) and paraventricular nucleus (PVN) of the hypothalamus is sensitive to increased plasma osmolality and a decreased blood volume, and thus is robustly increased by both dehydration (increased plasma osmolality and decreased blood volume) and salt loading (increased plasma osmolality). Both stimuli result in functional remodelling of the SON and PVN, a process referred to as functional-related plasticity. Such plastic changes in the brain have recently been associated with altered patterns of DNA methylation at CpG (cytosine-phosphate-guanine) residues, a process considered to be important for the regulation of gene transcription. In this regard, the proximal Avp promoter contains a number of CpG sites and is recognised as one of four CpG islands for the Avp gene, suggesting that methylation may be regulating Avp transcription. In the present study, we show that, in an immortalised hypothalamic cell line 4B, the proximal Avp promoter is highly methylated, and treatment of these cells with the DNA methyltransferase inhibitor 5-Aza-2'-deoxycytidine to demethylate DNA dramatically increases basal and stimulated Avp biosynthesis. We report no changes in the expression of DNA methyltransferases, Dnmt1 and Dnmt3a, whereas there is decreased expression of the demethylating enzyme ten-eleven-translocation 2, Tet2, in the SON by dehydration and salt loading. We found higher methylation of the SON Avp promoter in dehydrated but not salt-loaded rats. By analysis of individual CpG sites, we observed hypomethylation, hypermethylation and no change in methylation of specific CpGs in the SON Avp promoter of the dehydrated rat. Using reporter gene assays, we show that mutation of individual CpGs can result in altered Avp promoter activity. We propose that methylation of the SON Avp promoter is necessary to co-ordinate the duel inputs of increased plasma osmolality and decreased blood volume on Avp transcription in the chronically dehydrated rat.


Assuntos
Metilação de DNA/genética , Desidratação/genética , Epigênese Genética/genética , Regiões Promotoras Genéticas/genética , Cloreto de Sódio/metabolismo , Vasopressinas/genética , Animais , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Linhagem Celular , DNA (Citosina-5-)-Metiltransferase 1/biossíntese , DNA (Citosina-5-)-Metiltransferases/metabolismo , DNA Metiltransferase 3A , Decitabina , Desmetilação/efeitos dos fármacos , Hipotálamo/metabolismo , Masculino , Mutação , Concentração Osmolar , Ratos , Cloreto de Sódio/farmacologia
15.
Oecologia ; 180(2): 551-66, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26453520

RESUMO

Despite many studies highlighting the widespread occurrence and effects of resource movement between ecosystems, comparatively little is known about how anthropogenic alterations to ecosystems affect the strength, direction and importance of such fluxes. Hydrological regime and riparian land use cause well-documented changes in riverine larval invertebrate communities. Using a dataset from 66 sites collected over 20 years, we showed that such effects led to spatial and temporal differences in the density and type of larvae with winged adults within a river reach, altering the size and composition of the source pool from which adult aquatic insects can emerge. Mean annual larval densities varied 33-fold and the temporal range varied more than 20-fold between sites, associated with the hydrological regime and land cover and antecedent high and low flows, respectively. Densities of larvae with winged adults were greater in sites that had more algal coverage, agricultural land use, seasonally predictable flow regimes and faster water velocities. More interestingly, by influencing larval communities, riparian land use and the magnitude and frequency of high and low flows affected the size structure, dispersal ability and longevity of adults available to emerge from river reaches, potentially influencing the spatial extent and type of terrestrial consumers supported by aquatic prey. This suggests that anthropogenic alterations to land use or river flows will have both spatial and temporal effects on the flux and potential availability of adult aquatic insects to terrestrial consumers in many rivers.


Assuntos
Agricultura , Distribuição Animal , Ecossistema , Insetos/fisiologia , Plantas , Rios , Água , Animais , Meio Ambiente , Hidrologia , Larva , Longevidade , Comportamento Predatório , Estações do Ano
16.
Ann Oncol ; 26(4): 774-779, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25605745

RESUMO

BACKGROUND: For patients with peripheral T-cell lymphoma (PTCL), the value of (18)fluoro-deoxyglucose positron emission tomography (FDG-PET) scans for assessing prognosis and response to treatment remains unclear. The utility of FDG-PET, in addition to conventional radiology, was examined as a planned exploratory end point in the pivotal phase 2 trial of romidepsin for the treatment of relapsed/refractory PTCL. PATIENTS AND METHODS: Patients received romidepsin at a dose of 14 mg/m(2) on days 1, 8, and 15 of 28-day cycles. The primary end point was the rate of confirmed/unconfirmed complete response (CR/CRu) as assessed by International Workshop Criteria (IWC) using conventional radiology. For the exploratory PET end point, patients with at least baseline FDG-PET scans were assessed by IWC + PET criteria. RESULTS: Of 130 patients, 110 had baseline FDG-PET scans, and 105 were PET positive at baseline. The use of IWC + PET criteria increased the objective response rate to 30% compared with 26% by conventional radiology. Durations of response were well differentiated by both conventional radiology response criteria [CR/CRu versus partial response (PR), P = 0.0001] and PET status (negative versus positive, P < 0.0001). Patients who achieved CR/CRu had prolonged progression-free survival (PFS, median 25.9 months) compared with other response groups (P = 0.0007). Patients who achieved PR or stable disease (SD) had similar PFS (median 7.2 and 6.3 months, respectively, P = 0.6427). When grouping PR and SD patients by PET status, patients with PET-negative versus PET-positive disease had a median PFS of 18.2 versus 7.1 months (P = 0.0923). CONCLUSIONS: Routine use of FDG-PET does not obviate conventional staging, but may aid in determining prognosis and refine response assessments for patients with PTCL, particularly for those who do not achieve CR/CRu by conventional staging. The optimal way to incorporate FDG-PET scans for patients with PTCL remains to be determined. TRIAL REGISTRATION: NCT00426764.


Assuntos
Antibióticos Antineoplásicos/uso terapêutico , Depsipeptídeos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Fluordesoxiglucose F18/farmacocinética , Linfoma de Células T Periférico/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/estatística & dados numéricos , Seguimentos , Humanos , Linfoma de Células T Periférico/tratamento farmacológico , Linfoma de Células T Periférico/mortalidade , Linfoma de Células T Periférico/patologia , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Compostos Radiofarmacêuticos/farmacocinética , Indução de Remissão , Taxa de Sobrevida , Distribuição Tecidual
17.
Prim Dent J ; 3(1): 46-51, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25198330

RESUMO

The management of medical emergencies is clearly of vital importance in dental practice. The starting point of training in this area is the undergraduate dental degree programme. The aim of this study was to examine the opinions of final-year dental students at Newcastle School of Dental Sciences in relation to their undergraduate training in medical emergency management. Overall the responses were positive but the need for further practical training in the use of emergency drugs and equipment was highlighted.


Assuntos
Atitude do Pessoal de Saúde , Educação em Odontologia , Medicina de Emergência/educação , Estudantes de Odontologia/psicologia , Competência Clínica , Estudos de Coortes , Emergências , Tratamento de Emergência/instrumentação , Tratamento de Emergência/métodos , Inglaterra , Feminino , Humanos , Masculino , Anamnese , Preparações Farmacêuticas/administração & dosagem , Autoeficácia
18.
Br Dent J ; 217(3): 129-32, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25104692

RESUMO

At some stage in clinical practice all dental practitioners will encounter patients with disorders of the immune system. It is therefore important that dental practitioners are aware of the potential implications for safe practice. This paper summarises some of the more common immunological disorders that may be encountered, together with a basic review of immunological processes from a clinical perspective.


Assuntos
Doenças do Sistema Imunitário/diagnóstico , Doenças da Boca/diagnóstico , Doenças da Boca/terapia , Administração da Prática Odontológica , Anafilaxia/imunologia , Humanos , Hipersensibilidade/diagnóstico , Doenças do Sistema Imunitário/terapia
19.
Transpl Infect Dis ; 16(5): 751-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25040633

RESUMO

BACKGROUND: Allogeneic hematopoietic stem cell transplantation (alloHSCT) recipients are at high risk of invasive pneumococcal disease (IPD). We investigated the incidence and risk factors of IPD in alloHSCT recipients from 4 regional transplant centers over an 11-year period. This study aimed to inform future improvements in post-transplant care. METHODS: We conducted a retrospective nested 1:2 case-control study in patients aged ≥18 years who underwent alloHSCT between 2001 and 2011 in 4 major allogeneic transplant centers. Controls were matched with IPD cases on the basis of conditioning intensity and donor relationship (related or unrelated). Demographics and clinical characteristics of cases and controls were summarized. Univariate analysis of risk factors in matched case-control sets, and multivariate conditional logistic regression to control for confounding, were performed. RESULTS: In 23 alloHSCT recipients, 26 IPD episodes were identified. The cumulative incidence over 11 years was 2.3% (95% confidence interval [CI] 1.45-3.15) and the incidence density 956 per 100,000 transplant years of follow-up (95% CI 580-1321). Multivariate risk factor analysis and backwards elimination showed a significant positive association between mycophenolate mofetil (MMF), hyposplenism/asplenia, and IPD, whereas trimethoprim-sulfamethoxazole (TMP/SMX) prophylaxis for Pneumocystis jirovecii pneumonia (PJP) was associated with lower odds of IPD cases. Of alloHSCT recipients with IPD, 38.5% required intensive care, and, of deaths documented in cases over the period of review, 30% were attributable to IPD. Serotypes causing IPD matched currently available vaccines in 15/22 (68.1%) episodes. CONCLUSIONS: The incidence of IPD in alloHSCT recipients is an important cause of morbidity and mortality, with rates of disease being many fold higher than the general population. Patients with evidence of hyposplenism/asplenia define a high-risk group in the alloHSCT population for IPD, and the independent association with IPD and MMF in the adjusted model from this study requires further evaluation. The occurrence of post-transplant IPD may be reduced by measures such as vaccination with both 13-valent and 23-valent pneumococcal vaccines. TMP/SMX prophylaxis for the prevention of PJP may offer incidental protection against IPD in alloHSCT recipients.


Assuntos
Anti-Infecciosos/uso terapêutico , Antibioticoprofilaxia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Infecções Pneumocócicas/epidemiologia , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Hospedeiro Imunocomprometido , Imunossupressores/uso terapêutico , Incidência , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/uso terapêutico , Infecções Pneumocócicas/microbiologia , Estudos Retrospectivos , Fatores de Risco , Sorotipagem , Baço/anormalidades , Streptococcus pneumoniae/classificação , Transplante Homólogo , Adulto Jovem
20.
Endocrinology ; 155(10): 3934-44, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25051447

RESUMO

Prolonged exposure to environmental stress activates the hypothalamic-pituitary-adrenal (HPA) axis and generally disrupts the hypothalamic-pituitary-gonadal axis. Because CRF expression in the central nucleus of the amygdala (CeA) is a key modulator in adaptation to chronic stress, and central administration of CRF inhibits the hypothalamic GnRH pulse generator, we tested the hypothesis that overexpression of CRF in the CeA of female rats alters anxiety behavior, dysregulates the HPA axis response to stress, changes pubertal timing, and disrupts reproduction. We used a lentiviral vector to increase CRF expression site specifically in the CeA of preweaning (postnatal day 12) female rats. Overexpression of CRF in the CeA increased anxiety-like behavior in peripubertal rats shown by a reduction in time spent in the open arms of the elevated plus maze and a decrease in social interaction. Paradoxically, puberty onset was advanced but followed by irregular estrous cyclicity and an absence of spontaneous preovulatory LH surges associated with proestrous vaginal cytology in rats overexpressing CRF. Despite the absence of change in basal corticosterone secretion or induced by stress (lipopolysaccharide or restraint), overexpression of CRF in the CeA significantly decreased lipopolysaccharide, but not restraint, stress-induced suppression of pulsatile LH secretion in postpubertal ovariectomized rats, indicating a differential stress responsivity of the GnRH pulse generator to immunological stress and a potential adaptation of the HPA axis to chronic activation of amygdaloid CRF. These data suggest that the expression profile of this key limbic brain CRF system might contribute to the complex neural mechanisms underlying the increasing incidence of early onset of puberty on the one hand and infertility on the other attributed to chronic stress in modern human society.


Assuntos
Tonsila do Cerebelo/metabolismo , Hormônio Liberador da Corticotropina/genética , Ciclo Estral/efeitos dos fármacos , Maturidade Sexual/genética , Animais , Hormônio Liberador da Corticotropina/metabolismo , Feminino , Células HEK293 , Humanos , Infertilidade Feminina/genética , Infertilidade Feminina/metabolismo , Hormônio Luteinizante/sangue , Ratos , Ratos Sprague-Dawley , Ratos Transgênicos , Estresse Psicológico/sangue , Estresse Psicológico/genética , Regulação para Cima/genética
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