RESUMEN
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.
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Meniscos Tibiales , Lesiones de Menisco Tibial , Humanos , Adolescente , Adulto Joven , Adulto , Meniscos Tibiales/diagnóstico por imagen , Meniscos Tibiales/cirugía , Artroscopía/métodos , Estudios de Seguimiento , Lesiones de Menisco Tibial/diagnóstico por imagen , Lesiones de Menisco Tibial/cirugía , Articulación de la Rodilla , Imagen por Resonancia Magnética , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
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.
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Lesiones del Ligamento Cruzado Anterior/cirugía , Reconstrucción del Ligamento Cruzado Anterior , Resultado del Tratamiento , Adolescente , Adulto , Factores de Edad , Anciano , Femenino , Humanos , Inestabilidad de la Articulación/cirugía , Rodilla/cirugía , Traumatismos de la Rodilla/cirugía , Articulación de la Rodilla/cirugía , Escala de Puntuación de Rodilla de Lysholm , Masculino , Persona de Mediana Edad , Periodo Posoperatorio , Adulto JovenRESUMEN
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.
Asunto(s)
Medios de Cultivo , Francisella tularensis/crecimiento & desarrollo , Tularemia/prevención & control , Vacunas Atenuadas/inmunología , Animales , Francisella tularensis/inmunología , Factores de Tiempo , Tularemia/microbiologíaRESUMEN
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.
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Cavidad Glenoidea/cirugía , Osteoartritis/cirugía , Rango del Movimiento Articular , Articulación del Hombro/cirugía , Adulto , Femenino , Cavidad Glenoidea/diagnóstico por imagen , Cavidad Glenoidea/fisiopatología , Hemiartroplastia/métodos , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Osteoartritis/diagnóstico por imagen , Osteoartritis/fisiopatología , Complicaciones Posoperatorias , Reoperación , Reproducibilidad de los Resultados , Articulación del Hombro/diagnóstico por imagen , Articulación del Hombro/fisiopatologíaRESUMEN
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.
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Predisposición Genética a la Enfermedad , Esquizofrenia/genética , Esquizofrenia/terapia , Humanos , Canales Iónicos/metabolismo , Receptores de Superficie Celular/metabolismo , Factores de Riesgo , Investigación Biomédica TraslacionalRESUMEN
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.
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Circuncisión Masculina/normas , Medicina Basada en la Evidencia/normas , Política de Salud , Médicos/normas , Australasia/epidemiología , Circuncisión Masculina/efectos adversos , Prepucio/fisiología , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Humanos , Lactante , Masculino , Neoplasias del Pene/epidemiología , Neoplasias del Pene/prevención & control , Ensayos Clínicos Controlados Aleatorios como Asunto/normas , Enfermedades de Transmisión Sexual/epidemiología , Enfermedades de Transmisión Sexual/prevención & control , Infecciones Urinarias/epidemiología , Infecciones Urinarias/prevención & controlRESUMEN
The formation of the active spliceosome, its recruitment to active areas of transcription, and its role in pre-mRNA splicing depends on the association of a number of multifunctional serine/arginine-rich (SR) proteins. ZNF265 is an arginine/serine-rich (RS) domain containing zinc finger protein with conserved pre-mRNA splicing protein motifs. Here we show that ZNF265 immunoprecipitates from splicing extracts in association with mRNA, and that it is able to alter splicing patterns of Tra2-beta1 transcripts in a dose-dependent manner in HEK 293 cells. Yeast two-hybrid analysis and immunoprecipitation indicated interaction of ZNF265 with the essential splicing factor proteins U1-70K and U2AF(35). Confocal microscopy demonstrated colocalization of ZNF265 with the motor neuron gene product SMN, the snRNP protein U1-70K, the SR protein SC35, and with the transcriptosomal components p300 and YY1. Transfection of HT-1080 cells with ZNF265-EGFP fusion constructs showed that nuclear localization of ZNF265 required the RS domain. Alignment with other RS domain-containing proteins revealed a high degree of SR dipeptide conservation. These data show that ZNF265 functions as a novel component of the mRNA processing machinery.
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Empalme Alternativo , Proteínas de Unión al ARN/química , Proteínas de Unión al ARN/fisiología , Empalmosomas/fisiología , Transporte Activo de Núcleo Celular , Secuencia de Aminoácidos , Arginina/química , Western Blotting , Línea Celular , Núcleo Celular/metabolismo , Clonación Molecular , Secuencia Conservada , Relación Dosis-Respuesta a Droga , Técnica del Anticuerpo Fluorescente Indirecta , Humanos , Microscopía Confocal , Microscopía Fluorescente , Modelos Genéticos , Datos de Secuencia Molecular , Plásmidos/metabolismo , Pruebas de Precipitina , Estructura Terciaria de Proteína , ARN Mensajero/metabolismo , Homología de Secuencia de Aminoácido , Serina/química , Transfección , Técnicas del Sistema de Dos HíbridosRESUMEN
Specific oligonucleotide probes have been used to visualize the regional and cellular distribution of the mRNAs encoding three structurally distinct GABAA receptor alpha subunits in bovine brain. In situ hybridization analysis showed that these transcripts differ in distribution and in relative abundance. In frontal cortex the alpha 1 and alpha 2 transcripts are most abundant in layers II-IV, whereas the alpha 3 mRNA is most abundant in layers V and VI. In the hippocampal complex, the alpha transcripts are differentially distributed in the entorhinal cortex and subiculum. The alpha 2 transcript is enriched in the dentate gyrus and CA4/CA3 regions of the hippocampus. In the cerebellum, essentially only the alpha 1 transcript is detectable in granule cells, Purkinje cells, and stellate/basket cells. These results suggest that the different alpha subunits represent components of distinct GABAA receptor subtypes.
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Encéfalo/metabolismo , ARN Mensajero/genética , Receptores de GABA-A/genética , Animales , Secuencia de Bases , Encéfalo/citología , Encéfalo/ultraestructura , Bovinos , Cerebelo/citología , Cerebelo/metabolismo , Cerebelo/ultraestructura , Corteza Cerebral/citología , Corteza Cerebral/metabolismo , Corteza Cerebral/ultraestructura , ADN/genética , Expresión Génica , Hipocampo/citología , Hipocampo/metabolismo , Hipocampo/ultraestructura , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico , Sondas de Oligonucleótidos , ARN Mensajero/metabolismo , Receptores de GABA-A/metabolismoRESUMEN
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.
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Antipsicóticos/uso terapéutico , Corteza Prefrontal/patología , Esquizofrenia/tratamiento farmacológico , Esquizofrenia/patología , Animales , Antipsicóticos/farmacología , Modelos Animales de Enfermedad , Antagonistas de Aminoácidos Excitadores , Humanos , Fenciclidina , Corteza Prefrontal/efectos de los fármacos , Psicosis Inducidas por Sustancias/tratamiento farmacológico , Psicosis Inducidas por Sustancias/psicología , Ácido gamma-Aminobutírico/fisiologíaAsunto(s)
Hipertensión/genética , Mutación/genética , Receptores de Glucagón/genética , Femenino , Humanos , MasculinoRESUMEN
The frequency of the D allele of an insertion/deletion (I/D) polymorphism of the angiotensin I-converting enzyme (ACE) gene has been reported to be elevated in myocardial infarction and other patients. We therefore hypothesized that death rate of DD individuals should be increased in the population as a whole and this should be evident as a decrease in DD frequency with age. This hypothesis was tested in 118 Caucasian subjects who were already at high risk of cardiovascular events by having severe, early onset, familial hypertension (HT). A group of 196 age-, sex- and body mass index-matched normotensives (NTs) was used as a control. In the NT group II, ID, and DD genotype frequencies were similar for different age groups. DD frequency was 0.42 in NTs, but in HTs was 0.28, 0.26, and 0.10 for the age groups < 50, 50-59, and > or = 60 yr, respectively. Corresponding D allele frequencies were 0.52, 0.46, and 0.40 in the respective age groups of HTs, compared with 0.61 in NTs (by chi 2-analysis, P = 0.1, 0.047, and 0.0006, respectively). In HTs aged > or = 60, DD frequency was only 14% of expected. Plasma ACE activity tracked similarly with I/D genotype in HTs (P = 0.027; n = 35) as in NTs (P = 0.0001; n = 94) and Michaelis constant was identical for DD and II. Neither blood pressure, body mass index, nor sex bore any relationship with I/D genotype. In conclusion, in a group of severely HT patients not selected for cardiac pathology, there appeared to be a marked, selective decrease, in subgroups of increasing age, in frequency of the ACE DD genotype. One possibility suggested by this data might be that DD increases risk of premature death, at least in HTs who have two HT parents.
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Hipertensión/enzimología , Peptidil-Dipeptidasa A/genética , Polimorfismo Genético , Adulto , Factores de Edad , Alelos , Presión Sanguínea , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/genética , Colesterol/sangre , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Elementos Transponibles de ADN , Femenino , Eliminación de Gen , Frecuencia de los Genes , Genotipo , Humanos , Hipertensión/genética , Masculino , Persona de Mediana Edad , Valores de Referencia , Factores Sexuales , Triglicéridos/sangre , Población BlancaRESUMEN
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.
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Atención/fisiología , Cognición/fisiología , Haploinsuficiencia/genética , MAP Quinasa Quinasa 7/genética , Minociclina/farmacología , Esquizofrenia/genética , Animales , Atención/efectos de los fármacos , Conducta de Elección/efectos de los fármacos , Conducta de Elección/fisiología , Cognición/efectos de los fármacos , Femenino , Humanos , MAP Quinasa Quinasa 7/deficiencia , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Minociclina/uso terapéutico , Tiempo de Reacción/efectos de los fármacos , Tiempo de Reacción/genética , Factores de Riesgo , Esquizofrenia/tratamiento farmacológicoRESUMEN
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.
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Calcio/metabolismo , AMP Cíclico/metabolismo , Quinasa 2 de Adhesión Focal/metabolismo , Hipocampo/fisiología , Potenciación a Largo Plazo/fisiología , Alcaloides , Animales , Benzofenantridinas , Calcimicina/antagonistas & inhibidores , Calcimicina/farmacología , Colforsina/antagonistas & inhibidores , Colforsina/farmacología , Hipocampo/metabolismo , Immunoblotting , Inmunoprecipitación , Fenantridinas/farmacología , Fosforilación/efectos de los fármacos , Proteína Quinasa C/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores de N-Metil-D-Aspartato/metabolismo , Estaurosporina/farmacologíaRESUMEN
In the granule cells of the hippocampus, glutamate coexists with opioid peptides derived from the proenkephalin and prodynorphin genes. The functional significance of this coexistence has been unclear but recent evidence suggests that the dynorphins and enkephalins play a crucial role in regulating the efficiency of neurotransmission at granule-cell synapses. Together with evidence that the level of opioid activity in this pathway can change dramatically according to the physiological or pathological state of the tissue, this information focuses attention on granule-cell opioids as primary mediators of hippocampal plasticity.
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Endorfinas/fisiología , Hipocampo/metabolismo , Plasticidad Neuronal/fisiología , Animales , Endorfinas/genética , Encefalinas/genética , Encefalinas/fisiología , Hipocampo/fisiología , Humanos , Precursores de Proteínas/genética , Precursores de Proteínas/fisiologíaRESUMEN
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.
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Antipsicóticos/farmacología , Citocinas/biosíntesis , Antagonistas de Aminoácidos Excitadores/toxicidad , Fenciclidina/toxicidad , Corteza Prefrontal/metabolismo , Esquizofrenia/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Animales , Clozapina/farmacología , Interacciones Farmacológicas , Femenino , Expresión Génica/efectos de los fármacos , Haloperidol/farmacología , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Corteza Prefrontal/efectos de los fármacos , ARN/biosíntesis , ARN/aislamiento & purificación , Ratas , Ratas Long-Evans , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
1. The renin present in human amniotic fluid was found to have an apparent Mr of 58 000 by gel filtration and is thus bigger than renin in untreated kidney extracts and plasma (Mr approximately 40 000). 2. Treatment with pepsin (40 microgram/ml pH 4.8, 2 h, 22 degrees C) caused a 6-fold increase in activity of this renin species, although Mr was not very different (57 000). 3. Unlike renal renin, renin in human amniotic fluid was not a glycoprotein and behaved similarly on concanavalin A-Sepharose before and after activation by pepsin. 4. Ion-exchange chromatography demonstrated a small change in the ionization properties of human amniotic fluid renin after activation by pepsin. 5. Pepsin-mediated activation resulted in a five-fold increase in V, but only a small decrease in the Km of renin to 39% of normal, so that the increase in activity observed was not due to an increase in the affinity of the enzyme for its substrate. The kinetic data were consistent with the theory of noncompetitive inhibition. 6. The activation of human amniotic fluid renin by pepsin may be caused by a change in the tertiary structure of the molecule subsequent to a proteolytic action that does not remove detectable polypeptide components.
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Líquido Amniótico/enzimología , Pepsina A/metabolismo , Renina/metabolismo , Cromatografía de Afinidad , Concanavalina A , Activación Enzimática , Femenino , Humanos , Riñón/enzimología , Cinética , Peso Molecular , Embarazo , Renina/aislamiento & purificación , SefarosaRESUMEN
Puff adder venom, which has been pretreated with phenylmethylsulphonyl fluoride and extensively dialysed, is capable of destroying selectively proteinase inhibitory activity in human plasma by an action of an EDTA-sensitive venom proteinase. We found that incubation of 1/5 vol. of such venom with human plasma at 25 degrees C leads to a concomitant increase in renin to 4.4 times control by 5 h. The activation of inactive renin was abolished by 10 mM EDTA and the rate of activation was reduced by 50% in the presence of 5 mM phenylmethylsulphonyl fluoride and by 90% when 0.32 mg/ml soybean trypsin inhibitor and 5 mM N-ethylmaleimide were added as well. The venom proteinase thus appears to activate inactive renin via an activation of endogenous plasma proteinases. This may be accomplished either by activation of proteinase precursors or action on proteinase inhibitor-proteinase complexes. By destroying proteinase inhibitors at the same time as it activates endogenous proteinases, Bitis arietans metalloproteinase would appear to be particularly useful for studies of the activation of inactive renin in human plasma, since endogenous proteinases are then free to activate inactive renin without subsequent inhibition by endogenous proteinase inhibitors.
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Endopeptidasas/metabolismo , Inhibidores de Proteasas/sangre , Renina/metabolismo , Animales , Activación Enzimática , Humanos , Venenos de Víboras/metabolismoRESUMEN
Venom of the puff adder (Bitis arietans) contains a potent, basic, Mr 24,000 metalloproteinase activity that can destroy all detectable trypsin and chymotrypsin inhibitory activity, when venom is incubated with human plasma. We have found that during such incubation, concomitant activation of inactive renin occurs. In an examination of the mechanism involved we now report the activation, in addition, of plasma prekallikrein and serine proteinase activity, but not plasminogen, when human plasma is incubated with venom. Furthermore, venom was not able to release active trypsin from its complex with alpha 1-proteinase inhibitor and human renin was not inhibited by alpha 1-proteinase inhibitor. The activities in venom and venom/plasma mixtures were analysed using Sephacryl S-200 gel filtration and the effect of 10 mM EDTA and 5 mM phenylmethanesulphonyl fluoride on activities in column fractions was tested. The inactive-renin-activating, plasma prekallikrein-activating and serine proteinase-activating activities could be accounted for to a large extent by a venom metalloproteinase which was estimated to have a Mr of 24,000 by sodium dodecyl sulphate (SDS)-polyacrylamide gel electrophoresis. This enzyme activity appeared to complex with alpha 2-macroglobulin when venom was mixed with plasma. Since both EDTA and phenylmethanesulphonyl fluoride could inhibit the activation of inactive renin by this metalloproteinase, it is suggested that the enzyme activates serine proteinase(s), which then activate inactive renin. Plasma kallikrein may have a role in this process. Additional peaks of inactive-renin-activating activity eluted from Sephacryl S-200 at Mr 30,000 and 80,000 (minor) and an additional, minor peak of caseinolytic activity eluted at Mr 60,000. The Mr 24,000 metalloproteinase in venom may have considerable utility in activating inactive renin at physiological pH owing to its ability to destroy plasma proteinase inhibitors at the same time.
Asunto(s)
Renina/sangre , Venenos de Víboras/fisiología , Animales , Cromatografía en Gel , Endopeptidasas/sangre , Endopeptidasas/metabolismo , Activación Enzimática , Fibrinolisina/análisis , Humanos , Metaloendopeptidasas , Precalicreína/sangre , Inhibidores de Proteasas/metabolismo , Serina Endopeptidasas , Venenos de Víboras/análisisRESUMEN
In order to determine the influence of proximal 5'-flanking DNA of the human renin gene (REN) in cells that express human renin, transient expression analyses were carried out in chorio-decidual cells. Constructs containing different lengths of REN promoter DNA, extending as far as 2595 bp upstream of the transcription start site, were unable to drive transcription of a chloramphenicol acetyl transferase reporter gene in chorio-decidual cells, nor in noncognate 293 or JEG-3 cells. The tk promoter was similarly inactive in constructs containing -2595 to -453 fragments of REN 5'-flanking DNA. In each cell type, the -2595 to -1300 DNA exerted a negative influence. Additional promoter- and cell type-dependent negative influences were noted for other regions of REN 5'-flanking DNA and the -453 to -145 DNA increased tk promoter activity 2.5-fold in chorio-decidual cells. By introducing the SV40 enhancer into constructs, a weak stimulation of the REN promoter was observed in chorio-decidual cells, but not in noncognate, JEG-3 cells, although the -2595 to -1300 DNA retained its negative influence in the cognate cell type. These results show that the proximal 2.6 kb of REN 5'-flanking DNA is unable to drive reporter gene activity in renin-synthesizing, chorio-decidual cells under basal conditions and suggest that trans-acting factors unique to at least this cell type, together with enhancer(s) located outside of the proximal 2.6 kb of REN promoter DNA tested, could be required for human renin promoter activity.