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1.
Arch Orthop Trauma Surg ; 143(5): 2573-2579, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35927338

RESUMO

PURPOSE: The popliteomeniscal fascicles (PMFs) are a crucial part of the posterolateral corner of the knee. They provide stability to the lateral meniscus and stabilize the joint during tibial internal rotation. The clinical diagnosis of a torn PMFs is difficult, and magnetic resonance imaging (MRI) may be inconclusive as well. The aim of the present study was to report the outcomes of a continuous series of patients affected by PMF lesions and treated with an arthroscopic repair. METHODS: Seventeen patients (average age of 22 ± 3.6 years) with PMF lesions and lateral meniscus instability were prospectively enrolled. All patients were evaluated with clinical examination, International Knee Documentation Committee (IKDC), Lysholm and Tegner scores and 1.5 T MRI. All patients had the same arthroscopic procedure consisting of meniscal repair with an all-inside meniscal repair system (mean 2.2 ± 0.77 anchors) and followed with the same postoperative protocol. RESULTS: All patients were available at a mean follow-up of 68 ± 24 months (range 49-84 months). Mean IKDC increased from 60.2 ± 13.5 to 83.1 ± 12, mean Lysholm score improved from 56.7 ± 8.2 to 89.8 ± 3.2, and mean Tegner score improved from 2.9 ± 1.3 to 6.5 ± 2. No intraoperative or postoperative complications were reported. MRI evaluation at 6-month follow-up showed successful healing of the menisco-popliteal fascicles in all cases. CONCLUSIONS: The diagnosis and treatment of tears of the PMFs is still debated. Diagnostic confirmation of tearing of the PMFs is usually determined at the time of arthroscopy. Meniscal repair with an all-inside meniscal repair system appears to be an excellent treatment option, since it yields good functional results at mid-term follow-up, no local complications, and complete radiographic healing at 6-month follow-up MRI. Further studies are needed to confirm these promising early results. LEVEL OF EVIDENCE: Case series, 4.


Assuntos
Meniscos Tibiais , Lesões do Menisco Tibial , Humanos , Adolescente , Adulto Jovem , Adulto , Meniscos Tibiais/diagnóstico por imagem , Meniscos Tibiais/cirurgia , Artroscopia/métodos , Seguimentos , Lesões do Menisco Tibial/diagnóstico por imagem , Lesões do Menisco Tibial/cirurgia , Articulação do Joelho , Imageamento por Ressonância Magnética , Estudos Retrospectivos , Resultado do Tratamento
2.
Knee Surg Sports Traumatol Arthrosc ; 28(6): 1932-1945, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31463553

RESUMO

PURPOSE: The aim of the present meta-analysis was to update the literature on the outcomes and complications of ACL reconstruction in patients aged 40 years and older. It has been hypothesized that patients older than 40 years of age may have comparable clinical outcomes to those of younger patients. METHODS: A systematic review of articles from 1996 to 2018 was completed using Pubmed, Medline, Cochrane Reviews, and Google Scholar databases using the keyword terms "anterior cruciate ligament reconstruction" and "middle-aged OR elderly OR over 40 OR age factors." Functional and clinical outcomes (International Knee Documentation Committee, Lysholm and Tegner score and KT-1000 arthrometer), complication and graft failure rate were evaluated. RESULTS: Eleven articles met inclusion criteria. In total, 306 middle-aged patients and 566 younger patients were included in this study. The mean age of patients > 40 was 49 ± 7 (range 40-75) years with a mean follow-up of 25 ± 9 months (range 12-68). The mean age of younger patients was 26 ± 2.7 (range 15-39) years with a mean post-operative follow-up of 26.7 ± 11.5 months (range 3-64). The results were slightly higher (but no significantly different) towards the younger group in terms of objective IKDC (P = n.s.), Lysholm (P = n.s.) and Tegner (P = n.s.) scores and knee laxity assessment (P = n.s.). Complication rate (P = n.s.) and graft failure (P = n.s.) were low even in this cohort. CONCLUSIONS: The present meta-analysis shows that patients older than 40 years achieve comparable clinical outcomes to those of younger patients following primary ACL reconstruction. This evidence may push the surgeons toward a more aggressive approach in this specific cohort of patients. LEVEL OF EVIDENCE: III.


Assuntos
Lesões do Ligamento Cruzado Anterior/cirurgia , Reconstrução do Ligamento Cruzado Anterior , Resultado do Tratamento , Adolescente , Adulto , Fatores Etários , Idoso , Feminino , Humanos , Instabilidade Articular/cirurgia , Joelho/cirurgia , Traumatismos do Joelho/cirurgia , Articulação do Joelho/cirurgia , Escore de Lysholm para Joelho , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Adulto Jovem
3.
Arch Orthop Trauma Surg ; 137(7): 919-923, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28488015

RESUMO

INTRODUCTION: Symptomatic glenoid erosion is one of the most common causes of functional impairment after shoulder hemiarthroplasty. A decrease in the critical shoulder angle (CSA) has been associated with the development of shoulder arthritis. The inter-observer reliability of the CSA and the relationship between CSA and symptomatic glenoid erosion after shoulder hemiarthroplasty were investigated. MATERIALS AND METHODS: Twenty-eight patients with symptomatic glenoid erosion after anatomic hemiarthroplasty were compared to a control group of 30 patients with no signs of symptomatic glenoid erosion. The CSA was measured by two blinded shoulder surgeons at a mean follow-up of 105.2 and 54.7 months, respectively. The inter-observer reliability was calculated. RESULTS: The mean CSA in the control group in neutral, internal, and external rotations was 34°, 33°, and 33°, respectively. The corresponding values in the study group were 33°, 33°, and 33° (<0.01). The interclass correlation coefficient between the two examiners was 0.917 (P < 0.01), 0.924 (P < 0.01), and 0.948 (P < 0.01), respectively. The Mann-Whitney test between the control group and the study group were, respectively, 0.907, 0.932, and 0.602. CONCLUSION: There were no significant differences of CSA values between the two groups. Good inter-observer reliability was found for the CSA method.


Assuntos
Cavidade Glenoide/cirurgia , Osteoartrite/cirurgia , Amplitude de Movimento Articular , Articulação do Ombro/cirurgia , Adulto , Feminino , Cavidade Glenoide/diagnóstico por imagem , Cavidade Glenoide/fisiopatologia , Hemiartroplastia/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Osteoartrite/diagnóstico por imagem , Osteoartrite/fisiopatologia , Complicações Pós-Operatórias , Reoperação , Reprodutibilidade dos Testes , Articulação do Ombro/diagnóstico por imagem , Articulação do Ombro/fisiopatologia
4.
Lett Appl Microbiol ; 64(6): 394-400, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28255998

RESUMO

Francisella tularensis is a fastidious organism that requires a lengthy incubation time in liquid growth media for detection. The objective of this study was to develop a medium formulation using readily available supplements that enhanced early growth of F. tularensis. Francisella tularensis live vaccine strain was used to evaluate the growth responses for each of the media formulations tested. Growth in brain heart infusion broth supplemented with 2% Vitox, 10% Fildes and 1% histidine (BVFH) resulted in a significant increase in growth after 8 h incubation compared to other media formulations tested (P < 0·001). Virulent strains of F. tularensis grown in BVFH medium demonstrated similar enhanced early growth. Cell densities of 3·9-5·2 log10 CFU per ml were obtained after 24 h of growth in BVFH from a 1-2 cell ml-1 starting inoculum of the virulent Type A Schu4 strain, indicating the suitability of this medium in rapidly amplifying low starting titres of F. tularensis. Collectively, these results indicate that the novel formulation of the BVFH medium was capable of producing enhanced growth response for F. tularensis. SIGNIFICANCE AND IMPACT OF THE STUDY: The need for rapid cultivation of Francisella tularensis is essential for detection and monitoring during natural outbreak events or intentional bioterrorism attacks. The addition of selected supplements into the base medium BHI (BVFH) developed in this study enhanced growth of F. tularensis Type A1, A2 and B strains compared to BHI alone. Growth of these organisms in BVFH will allow for improved response time should a natural or intentional contamination event occur.


Assuntos
Meios de Cultura , Francisella tularensis/crescimento & desenvolvimento , Tularemia/prevenção & controle , Vacinas Atenuadas/imunologia , Animais , Francisella tularensis/imunologia , Fatores de Tempo , Tularemia/microbiologia
5.
Psychopharmacology (Berl) ; 234(2): 293-305, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27774567

RESUMO

RATIONALE: Members of the c-Jun N-terminal kinase (JNK) family of mitogen-activated protein (MAP) kinases, and the upstream kinase MKK7, have all been strongly linked with synaptic plasticity and with the development of the neocortex. However, the impact of disruption of this pathway on cognitive function is unclear. OBJECTIVE: In the current study, we test the hypothesis that reduced MKK7 expression is sufficient to cause cognitive impairment. METHODS: Attentional function in mice haploinsufficient for Map2k7 (Map2k7 +/- mice) was investigated using the five-choice serial reaction time task (5-CSRTT). RESULTS: Once stable performance had been achieved, Map2k7 +/- mice showed a distinctive attentional deficit, in the form of an increased number of missed responses, accompanied by a more pronounced decrement in performance over time and elevated intra-individual reaction time variability. When performance was reassessed after administration of minocycline-a tetracycline antibiotic currently showing promise for the improvement of attentional deficits in patients with schizophrenia-signs of improvement in attentional performance were detected. CONCLUSIONS: Overall, Map2k7 haploinsufficiency causes a distinctive pattern of cognitive impairment strongly suggestive of an inability to sustain attention, in accordance with those seen in psychiatric patients carrying out similar tasks. This may be important for understanding the mechanisms of cognitive dysfunction in clinical populations and highlights the possibility of treating some of these deficits with minocycline.


Assuntos
Atenção/fisiologia , Cognição/fisiologia , Haploinsuficiência/genética , MAP Quinase Quinase 7/genética , Minociclina/farmacologia , Esquizofrenia/genética , Animais , Atenção/efeitos dos fármacos , Comportamento de Escolha/efeitos dos fármacos , Comportamento de Escolha/fisiologia , Cognição/efeitos dos fármacos , Feminino , Humanos , MAP Quinase Quinase 7/deficiência , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Minociclina/uso terapêutico , Tempo de Reação/efeitos dos fármacos , Tempo de Reação/genética , Fatores de Risco , Esquizofrenia/tratamento farmacológico
6.
Transl Psychiatry ; 5: e569, 2015 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-25989143

RESUMO

Considerable evidence implicates DISC1 as a susceptibility gene for multiple psychiatric diseases. DISC1 has been intensively studied at the molecular, cellular and behavioral level, but its role in regulating brain connectivity and brain network function remains unknown. Here, we utilize a set of complementary approaches to assess the functional brain network abnormalities present in mice expressing a truncated Disc1 gene (Disc1tr Hemi mice). Disc1tr Hemi mice exhibited hypometabolism in the prefrontal cortex (PFC) and reticular thalamus along with a reorganization of functional brain network connectivity that included compromised hippocampal-PFC connectivity. Altered hippocampal-PFC connectivity in Disc1tr Hemi mice was confirmed by electrophysiological analysis, with Disc1tr Hemi mice showing a reduced probability of presynaptic neurotransmitter release in the monosynaptic glutamatergic hippocampal CA1-PFC projection. Glutamate system dysfunction in Disc1tr Hemi mice was further supported by the attenuated cerebral metabolic response to the NMDA receptor (NMDAR) antagonist ketamine and decreased hippocampal expression of NMDAR subunits 2A and 2B in these animals. These data show that the Disc1 truncation in Disc1tr Hemi mice induces a range of translationally relevant endophenotypes underpinned by glutamate system dysfunction and altered brain connectivity.


Assuntos
Ácido Glutâmico/metabolismo , Hipocampo/fisiopatologia , Proteínas do Tecido Nervoso/genética , Córtex Pré-Frontal/fisiopatologia , Tálamo/fisiopatologia , Animais , Autorradiografia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Região CA1 Hipocampal/metabolismo , Região CA1 Hipocampal/fisiopatologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Hipocampo/metabolismo , Ketamina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Vias Neurais/metabolismo , Vias Neurais/fisiopatologia , Técnicas de Patch-Clamp , Córtex Pré-Frontal/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Transmissão Sináptica/fisiologia , Tálamo/metabolismo
7.
Clin Genet ; 86(5): 401-11, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25142969

RESUMO

Recent years have seen significant advances in our understanding of the genetic basis of schizophrenia. In particular, genome-wide approaches have suggested the involvement of many common genetic variants of small effect, together with a few rare variants exerting relatively large effects. While unequivocal identification of the relevant genes has, for the most part, remained elusive, the genes revealed as potential candidates can in many cases be clustered into functionally related groups which are potentially open to therapeutic intervention. In this review, we summarise this information, focusing on the accumulating evidence that genetic dysfunction at glutamatergic synapses and post-synaptic signalling complexes contributes to the aetiology of the disease. In particular, there is converging support for involvement of post-synaptic JNK pathways in disease aetiology. An expansion of our neurobiological knowledge of the basis of schizophrenia is urgently needed, yet some promising novel pharmacological targets can already be discerned.


Assuntos
Predisposição Genética para Doença , Esquizofrenia/genética , Esquizofrenia/terapia , Humanos , Canais Iônicos/metabolismo , Receptores de Superfície Celular/metabolismo , Fatores de Risco , Pesquisa Translacional Biomédica
9.
Intern Med J ; 42(7): 822-8, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22805686

RESUMO

Infant male circumcision (MC) is an important issue guided by Royal Australasian College of Physicians (RACP) policy. Here we analytically review the RACP's 2010 policy statement 'Circumcision of infant males'. Comprehensive evaluation in the context of published research was used. We find that the Statement is not a fair and balanced representation of the literature on MC. It ignores, downplays, obfuscates or misrepresents the considerable evidence attesting to the strong protection MC affords against childhood urinary tract infections, sexually transmitted infections (human immunodeficiency virus, human papilloma virus, herpes simplex virus type 2, trichomonas and genital ulcer disease), thrush, inferior penile hygiene, phimosis, balanoposthitis and penile cancer, and in women protection against human papilloma virus, herpes simplex virus type 2, bacterial vaginosis and cervical cancer. The Statement exaggerates the complication rate. Assertions that 'the foreskin has a functional role' and 'is a primary sensory part of the penis' are not supported by research, including randomised controlled trials. Instead of citing these and meta-analyses, the Statement selectively cites poor quality studies. Its claim, without support from a literature-based risk-benefit analysis, that the currently available evidence does 'not warrant routine infant circumcision in Australia and New Zealand' is misleading. The Statement fails to explain that performing MC in the neonatal period using local anaesthesia maximises benefits, safety, convenience and cost savings. Because the RACP's policy statement is not a fair and balanced representation of the current literature, it should not be used to guide policy. In the interests of public health and individual well-being, an extensive, comprehensive, balanced review of the scientific literature and a risk-benefit analysis should be conducted to formulate policy.


Assuntos
Circuncisão Masculina/normas , Medicina Baseada em Evidências/normas , Política de Saúde , Médicos/normas , Australásia/epidemiologia , Circuncisão Masculina/efeitos adversos , Prepúcio do Pênis/fisiologia , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Humanos , Lactente , Masculino , Neoplasias Penianas/epidemiologia , Neoplasias Penianas/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto/normas , Infecções Sexualmente Transmissíveis/epidemiologia , Infecções Sexualmente Transmissíveis/prevenção & controle , Infecções Urinárias/epidemiologia , Infecções Urinárias/prevenção & controle
10.
Int J STD AIDS ; 23(3): 153-9, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22581866

RESUMO

Here we provide an up-to-date review of research that explains why uncircumcised men are at higher risk of HIV infection. The inner foreskin is a mucosal epithelium deficient in protective keratin, yet rich in HIV target cells. Soon after sexual exposure to infected mucosal secretions of a HIV-positive partner, infected T-cells from the latter form viral synapses with keratinocytes and transfer HIV to Langerhans cells via dendrites that extend to just under the surface of the inner foreskin. The Langerhans cells with internalized HIV migrate to the basal epidermis and then pass HIV on to T-cells, thus leading to the systemic infection that ensues. Infection is exacerbated in inflammatory states associated with balanoposthitis, the presence of smegma and ulceration - including that caused by infection with herpes simplex virus type 2 and some other sexually transmitted infections (STIs). A high foreskin surface area and tearing of the foreskin or associated frenulum during sexual intercourse also facilitate HIV entry. Thus, by various means, the foreskin is the primary biological weak point that permits HIV infection during heterosexual intercourse. The biological findings could explain why male circumcision protects against HIV infection.


Assuntos
Circuncisão Masculina , Infecções por HIV/prevenção & controle , HIV/imunologia , HIV/patogenicidade , Internalização do Vírus , Humanos , Masculino
12.
Placenta ; 32(3): 214-21, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21215447

RESUMO

A prorenin-angiotensin system (RAS) could, via the (pro)renin receptor (ATP6AP2), have various effects in human intrauterine tissues, either directly by prorenin/ATP6AP2 cell signaling, or indirectly via angiotensin II and/or angiotensin 1-7. Here we describe RAS components in fetal membranes, decidua and placenta collected at elective cesarean section (non-laboring), after spontaneous delivery (after labor, n = 38), and in myometria (n = 16) from elective (non-laboring) or emergency cesarean (laboring) deliveries. Angiotensinogen (AGT), angiotensin-converting enzyme 1 and 2 (ACE; ACE2), angiotensin receptor 1 and 2 (AGTR1; AGTR2) and angiotensin 1-7 receptor (MAS1) mRNAs were measured by qRT-PCR and proteins were localized by immunohistochemistry. In myometrium, prorenin (REN), ATP6AP2, and downstream signaling proteins zinc finger and BTB domain-containing protein 16 (ZBTB16), transforming growth factor-ß1 (TGFß1) and prostaglandin-endoperoxide synthase 2 (PTGS2) mRNAs were also measured. RAS mRNAs, except AGTR1 and AGTR2, were abundant in decidua and lowest in amnion compared to the other tissues. ACE, AGT and PTGS2 mRNAs were higher in laboring than non-laboring myometrium, suggesting that the myometrial RAS is involved in labor. Angiotensinogen and prorenin staining in amnion, chorion and decidua was pervasive despite their mRNAs being low in amnion and chorion. In placenta, prorenin, angiotensinogen and AGTR2 were present in syncytiotrophoblasts, ACE was in fetal endothelium, while ACE2 distribution was diffuse. AGTR1 and AGTR2 mRNAs and proteins were abundant. No differences were evident in the staining patterns with labor. These results are consistent with the hypothesis that fetal vascular ACE might contribute angiotensin II to the fetus, whilst syncytial ACE2 might hypothetically have a role in converting angiotensin II to angiotensin 1-7 in maternal blood.


Assuntos
Membranas Extraembrionárias/fisiologia , Miométrio/fisiologia , Sistema Renina-Angiotensina/fisiologia , Cesárea , Feminino , Feto , Humanos , Gravidez , Proto-Oncogene Mas , RNA Mensageiro/química , RNA Mensageiro/genética , Sistema Renina-Angiotensina/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estatísticas não Paramétricas
13.
J. Public Health Africa (Online) ; 2(2): 117-122, 2011.
Artigo em Inglês | AIM (África) | ID: biblio-1263211

RESUMO

Despite over two decades of extensive research showing that male circumcision protects against heterosexual acquisition of HIV in men; and that includes findings from large randomized controlled trials leading to acceptance by the WHO/UNAIDS and the Cochrane Committee; opponents of circumcision continue to generate specious arguments to the contrary. In a recent issue of the Journal of Public Health in Africa; Van Howe and Storms claim that male circumcision will increase HIV infections in Africa. Here we review the statements they use in support of their thesis and show that there is no scientific basis to such an assertion. We also evaluate the statistics used and show that when these data are properly analyzed the results lead to a contrary conclusion affirming the major role of male circumcision in protecting against HIV infection in Africa. Researchers; policy makers and the wider community should rely on balanced scholarship when assessing scientific evidence. We trust that our assessment may help refute the claims by Van Howe and Storms; and provide reassurance on the importance of circumcision for HIV prevention


Assuntos
Circuncisão Masculina , Medicina Baseada em Evidências , Infecções por HIV , Masculino
15.
Br J Pharmacol ; 153 Suppl 1: S465-70, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18311160

RESUMO

Current treatments of schizophrenia are compromised by their inability to treat all symptoms of the disease and their side-effects. Whilst existing antipsychotic drugs are effective against positive symptoms, they have negligible efficacy against the prefrontal cortex (PFC)-associated cognitive deficits and negative symptoms. New models that reproduce core pathophysiological features of schizophrenia are more likely to have improved predictive validity in identifying new treatments. We have developed a NMDA receptor antagonist model that reproduces core PFC deficits of schizophrenia and discuss this in relation to pathophysiology and treatments. Subchronic and chronic intermittent PCP (2.6 mg/kg i.p.) was administered to rats. PFC activity was assessed by 2-deoxyglucose imaging, parvalbumin and Kv3.1 mRNA expression, and the attentional set-shifting test (ASST) of executive function. Affymetrix gene array technology was employed to examine gene expression profile patterns. PCP treatment reduced glucose utilization in the PFC (hypofrontality). This was accompanied by a reduction in markers of GABAergic interneurones (parvalbumin and Kv3.1 mRNA expression) and deficits in the extradimensional shift dimension of the ASST. Consistent with their clinical profile, the hypofrontality was not reversed by clozapine or haloperidol. Transcriptional analysis revealed patterns of change consistent with current neurobiological theories of schizophrenia. This model mirrors core neurobiological deficits of schizophrenia; hypofrontality, altered markers of GABAergic interneurone activity and deficits in executive function. As such it is likely to be a valuable translational model for understanding the neurobiological mechanisms underlying hypofrontality and for identifying and validating novel drug targets that may restore PFC deficits in schizophrenia.


Assuntos
Antipsicóticos/uso terapêutico , Córtex Pré-Frontal/patologia , Esquizofrenia/tratamento farmacológico , Esquizofrenia/patologia , Animais , Antipsicóticos/farmacologia , Modelos Animais de Doenças , Antagonistas de Aminoácidos Excitatórios , Humanos , Fenciclidina , Córtex Pré-Frontal/efeitos dos fármacos , Psicoses Induzidas por Substâncias/tratamento farmacológico , Psicoses Induzidas por Substâncias/psicologia , Ácido gama-Aminobutírico/fisiologia
17.
J Neurochem ; 102(4): 1024-34, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17663748

RESUMO

Activated extracellular-signal-regulated kinase (Erk) phosphorylates and activates downstream kinases including ribosomal S6 kinase 2 (Rsk2/RPS6KA3) and mitogen- and stress-activated kinase 1 (Msk1, RPS6KA5). Rsk2 plays an important role in neuronal plasticity, as patients with Coffin-Lowry syndrome, where Rsk2 is dysfunctional, have impaired cognitive function. However, the relative role of neuronal Rsk2 and Msk1 in activating proteins downstream of Erk is unclear. In PC12 cells and in cortical neurones, the calcium ionophore A23187-induced phosphorylation of Erk, Msk1, Rsk2 and also the Bcl-2-associated death protein (Bad), which protects against neurotoxicity. Specific knockdown of Msk1 with small interfering RNA reduced the ability of A23187 to induce Bad phosphorylation in both PC12 cells and cortical neurones. Conversely, specific knockdown of Rsk2 potentiated Bad phosphorylation following A23187 treatment, and also elevated Erk phosphorylation in both cell types. This indicates that Msk1 rather than Rsk2 mediates neuronal Bad phosphorylation following Ca(2+) influx and implicates Rsk2 in a negative-feedback regulation of Erk activity.


Assuntos
MAP Quinases Reguladas por Sinal Extracelular/fisiologia , Neurônios/metabolismo , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Transdução de Sinais/fisiologia , Proteína de Morte Celular Associada a bcl/metabolismo , Animais , Calcimicina/farmacologia , Células Cultivadas , Córtex Cerebral/citologia , Embrião de Mamíferos , Feminino , Ionóforos/farmacologia , Peso Molecular , Neurônios/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Gravidez , RNA Interferente Pequeno/farmacologia , Ratos , Proteínas Quinases S6 Ribossômicas 90-kDa/genética , Transdução de Sinais/efeitos dos fármacos
18.
J Psychopharmacol ; 20(5): 636-42, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16478754

RESUMO

The psychotomimetic drug phencyclidine (PCP) induces symptoms closely related to those of schizophrenia in humans. In order to test the hypothesis that cytokines may be involved in the aetiology and treatment of schizophrenia, this study investigated the levels of cytokine mRNAs in rat brain after acute and chronic administration of PCP, in the presence and absence of antipsychotic drugs. The levels of the mRNAs encoding TNF, IL-2, IL-6, TGF 1, 2, 3, IL-3 and GM-CSF were measured in the prefrontal cortex, cortex, hippocampus, ventral and dorsal striatum regions of male hooded Long Evans rats after acute drug administration. Antipsychotic drugs and PCP significantly reduced the levels of TNF in the prefrontal cortex compared to vehicle-treated animals, whilst other cytokines remained unchanged. In addition, significant reductions in the levels of TNF mRNA in the prefrontal cortex still occurred 24h after acute PCP administration. However, levels of TNF mRNA were restored to control values after chronic PCP treatment, whereas increased expression was detected in animals co-administered with haloperidol. Levels of TNF mRNA were also found to be significantly increased in the prefrontal cortex of schizophrenic subjects. The relationship between TNF levels and schizophrenia are discussed.


Assuntos
Antipsicóticos/farmacologia , Citocinas/biossíntese , Antagonistas de Aminoácidos Excitatórios/toxicidade , Fenciclidina/toxicidade , Córtex Pré-Frontal/metabolismo , Esquizofrenia/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Clozapina/farmacologia , Interações Medicamentosas , Feminino , Expressão Gênica/efeitos dos fármacos , Haloperidol/farmacologia , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Córtex Pré-Frontal/efeitos dos fármacos , RNA/biossíntese , RNA/isolamento & purificação , Ratos , Ratos Long-Evans , Reação em Cadeia da Polimerase Via Transcriptase Reversa
19.
Biochim Biophys Acta ; 1745(3): 342-9, 2005 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-16120467

RESUMO

Proline-rich tyrosine kinase 2 (Pyk2) is activated in neurones following NMDA receptor stimulation via PKC. Pyk2 is involved in hippocampal LTP and acts to potentiate NMDA receptor function. Elevations of intracellular Ca2+ and cAMP levels are key NMDA receptor-dependent triggering events leading to induction of hippocampal LTP. In this study, we compared the ability of A23187 (Ca2+ ionophore) or forskolin (adenylate cyclase activator) to modulate the phosphorylation of Pyk2 in rat hippocampal slices. Using an immunoprecipitation assay, phosphorylated Pyk2 levels were increased following treatment with A23187, levels peaking at around 10 min. Staurosporine, at concentrations inhibiting conventional and novel isoforms of PKC, and chelerythrine, at concentrations inhibiting the atypical PKC isoform PKMxi, were compared for their ability to attenuate the effect of A23187. Exposure of acute hippocampal slices to either chelerythrine or staurosporine completely blocked enhanced phosphorylation of Pyk2 by A23187, suggesting a possible involvement of PKMxi and typical PKCs in Pyk2 activation by Ca2+. In contrast, application of forskolin reduced phosphorylated Pyk2 below basal levels, suggesting that cAMP inhibits Pyk2. These results implicate Ca2+ and multiple forms of PKC in the activation of Pyk2 downstream of NMDA receptors and suggest that cAMP-dependent processes exert a suppressive action on Pyk2.


Assuntos
Cálcio/metabolismo , AMP Cíclico/metabolismo , Quinase 2 de Adesão Focal/metabolismo , Hipocampo/fisiologia , Potenciação de Longa Duração/fisiologia , Alcaloides , Animais , Benzofenantridinas , Calcimicina/antagonistas & inibidores , Calcimicina/farmacologia , Colforsina/antagonistas & inibidores , Colforsina/farmacologia , Hipocampo/metabolismo , Immunoblotting , Imunoprecipitação , Fenantridinas/farmacologia , Fosforilação/efeitos dos fármacos , Proteína Quinase C/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/metabolismo , Estaurosporina/farmacologia
20.
Mol Pharmacol ; 67(4): 1158-65, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15625280

RESUMO

Stimulation of N-methyl-D-aspartate (NMDA) receptors is believed to underlie long-term memory formation, and excessive NMDA receptor activation has been linked to several neuropathological conditions. Phosphorylation and activation of p42/44 mitogen-activated protein kinase (ERK) is believed to mediate many of these effects, but the downstream targets of ERK in response to NMDA activation have not been determined. In primary cultures of rat cortical neurons, we found that NMDA was able to elevate phosphorylation of mitogen- and stress-activated kinase 1 (MSK1) as well as ERK. Likewise, brain-derived neurotrophic factor (BDNF) treatment increased phosphorylation of MSK1 and ERKs. The NMDA-induced MSK1 phosphorylation was sensitive to the MEK inhibitor 2'-amino-3'-methoxyflavone (PD98059) and the p38 inhibitor 4-(4-fluorophenyl)-2-(4-methylsulfinylphenyl)-5-(4-pyridyl)1H-imidazole (SB203580). MSK1 activation by NMDA was transient, although ERK remained phosphorylated within the neuronal cytoplasm for several hours. Although BDNF increased ribosomal S6 kinase (RSK) phosphorylation, NMDA had no discernable effect on the phosphorylation of RSKs. Thus, phosphorylation and activation of MSK1 but not RSK could be an important step in the pathway linking NMDA-induced ERK phosphorylation to the activation of transcription factors required for the formation of long-term memory.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/farmacologia , Córtex Cerebral/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , N-Metilaspartato/farmacologia , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Proteínas Quinases S6 Ribossômicas/metabolismo , Animais , Células Cultivadas , Córtex Cerebral/metabolismo , Flavonoides/farmacologia , Imidazóis/farmacologia , Fosforilação , Piridinas/farmacologia , Ratos
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