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^{140}Ce(n,γ) is a key reaction for slow neutron-capture (s-process) nucleosynthesis due to being a bottleneck in the reaction flow. For this reason, it was measured with high accuracy (uncertainty ≈5%) at the n_TOF facility, with an unprecedented combination of a high purity sample and low neutron-sensitivity detectors. The measured Maxwellian averaged cross section is up to 40% higher than previously accepted values. Stellar model calculations indicate a reduction around 20% of the s-process contribution to the Galactic cerium abundance and smaller sizeable differences for most of the heavier elements. No variations are found in the nucleosynthesis from massive stars.
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BACKGROUND: The pathophysiological mechanisms linking tricuspid regurgitation (TR) and chronic kidney disease (CKD) remain unknown. This study aimed to determine which pathophysiological mechanisms related to TR are independently associated with renal dysfunction and to evaluate the impact of renal impairment on long-term prognosis in patients with significant (≥ moderate) secondary TR. METHODS: A total of 1234 individuals (72 [IQR 63-78] years, 50% male) with significant secondary TR were followed up for the occurrence of all-cause mortality and the presence of significant renal impairment (eGFR of <60 mL min-1 1.73 m-2 ) at the time of baseline echocardiography. RESULTS: Multivariable analysis demonstrated that severe right ventricular (RV) dysfunction (TAPSE < 14 mm) was independently associated with the presence of significant renal impairment (OR 1.49, 95% CI 1.11 to 1.99, P = 0.008). Worse renal function was associated with a significant reduction in survival at 1 and 5 years (85% vs. 87% vs. 68% vs. 58% at 1 year, and 72% vs. 64% vs. 39% vs. 19% at 5 years, for stage 1, 2, 3 and 4-5 CKD groups, respectively, P < 0.001). The presence of severe RV dysfunction was associated with reduced overall survival in stage 1-3 CKD groups, but not in stage 4-5 CKD groups. CONCLUSIONS: Of the pathophysiological mechanisms identified by echocardiography that are associated with significant secondary TR, only severe RV dysfunction was independently associated with the presence of significant renal impairment. In addition, worse renal function according to CKD group was associated with a significant reduction in survival.
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Insuficiencia Renal Crónica , Insuficiencia de la Válvula Tricúspide , Disfunción Ventricular Derecha , Anciano , Femenino , Humanos , Riñón/diagnóstico por imagen , Riñón/fisiología , Masculino , Persona de Mediana Edad , Pronóstico , Insuficiencia Renal Crónica/complicaciones , Estudios Retrospectivos , Insuficiencia de la Válvula Tricúspide/diagnóstico por imagen , Disfunción Ventricular Derecha/diagnóstico por imagen , Disfunción Ventricular Derecha/etiologíaRESUMEN
Our brain is constantly extracting, predicting, and recognising key spatiotemporal features of the physical world in order to survive. While neural processing of visuospatial patterns has been extensively studied, the hierarchical brain mechanisms underlying conscious recognition of auditory sequences and the associated prediction errors remain elusive. Using magnetoencephalography (MEG), we describe the brain functioning of 83 participants during recognition of previously memorised musical sequences and systematic variations. The results show feedforward connections originating from auditory cortices, and extending to the hippocampus, anterior cingulate gyrus, and medial cingulate gyrus. Simultaneously, we observe backward connections operating in the opposite direction. Throughout the sequences, the hippocampus and cingulate gyrus maintain the same hierarchical level, except for the final tone, where the cingulate gyrus assumes the top position within the hierarchy. The evoked responses of memorised sequences and variations engage the same hierarchical brain network but systematically differ in terms of temporal dynamics, strength, and polarity. Furthermore, induced-response analysis shows that alpha and beta power is stronger for the variations, while gamma power is enhanced for the memorised sequences. This study expands on the predictive coding theory by providing quantitative evidence of hierarchical brain mechanisms during conscious memory and predictive processing of auditory sequences.
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Corteza Auditiva , Vías Auditivas , Giro del Cíngulo , Hipocampo , Memoria , Humanos , Música , Magnetoencefalografía , Análisis Multivariante , Patrones de Reconocimiento Fisiológico , Corteza Auditiva/fisiología , Giro del Cíngulo/fisiología , Hipocampo/fisiología , Corteza Prefrontal/fisiología , Potenciales Evocados Auditivos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Percepción AuditivaRESUMEN
Chronic and recurrent bone infections occur frequently but have not been explained. Staphylococcus aureus (S. aureus) is often found among chronic and recurrent infections and may be responsible for such infections. One possible reason is that S. aureus can internalize and survive within host cells and by doing so, S. aureus can evade both host defense mechanisms and most conventional antibiotic treatments. In this study, we hypothesized that intra-cellular S. aureus could induce infections in vivo. Osteoblasts were infected with S. aureus and, after eliminating extra-cellular S. aureus, inoculated into an open fracture rat model. Bacterial cultures and radiographic observations at post-operative day 21 confirmed local bone infections in animals inoculated with intra-cellular S. aureus within osteoblasts alone. We present direct in vivo evidence that intra-cellular S. aureus could be sufficient to induce bone infection in animals; we found that intra-cellular S. aureus inoculation of as low as 102 colony forming units could induce severe bone infections. Our data may suggest that intra-cellular S. aureus can "hide" in host cells during symptom-free periods and, under certain conditions, they may escape and lead to infection recurrence. Intra-cellular S. aureus therefore could play an important role in the pathogenesis of S. aureus infections, especially those chronic and recurrent infections in which disease episodes may be separated by weeks, months, or even years.
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Espacio Intracelular/microbiología , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/fisiología , Animales , Carga Bacteriana , Recuento de Células Sanguíneas , Peso Corporal , Fracturas del Fémur/sangre , Fracturas del Fémur/diagnóstico por imagen , Fracturas del Fémur/microbiología , Fracturas del Fémur/patología , Fémur/diagnóstico por imagen , Fémur/microbiología , Fémur/patología , Fémur/cirugía , Músculos/microbiología , Músculos/patología , Osteoblastos/microbiología , Osteoblastos/patología , Osteoblastos/ultraestructura , Radiografía , Ratas , Infecciones Estafilocócicas/sangre , Infecciones Estafilocócicas/diagnóstico por imagen , Infecciones Estafilocócicas/patología , Staphylococcus aureus/ultraestructuraRESUMEN
BACKGROUND: Peritoneal mesothelioma (PeM) is a rare malignancy with a poor prognosis. Currently there is a lack of effective systemic therapies. Due to the rarity of PeM, it is challenging to study new treatment options. Off-label use of targeted drugs could be an effective approach. This scoping review aims to explore the genomic landscape of PeM to identify potential therapeutic targets. MATERIALS AND METHODS: A systematic literature search of Embase, Medline, Web of Science, the Cochrane Library, and Google Scholar was carried out up to 1 November 2022. Studies that reported on molecular alterations in PeM detected by high-throughput sequencing techniques were included. Genes that were altered in ≥1% of PeMs were selected for the identification of potential targeted therapies. RESULTS: Thirteen articles were included, comprising 824 PeM patients. In total, 142 genes were altered in ≥1% of patients, of which 7 genes were altered in ≥10%. BAP1 was the most commonly altered gene (50%). Other commonly altered genes were NF2 (25%), CDKN2A (23%), CDKN2B (17%), PBRM1 (15%), TP53 (14%), and SETD2 (13%). In total, 17% of PeM patients were carriers of a germline mutation, mainly in BAP1 (7%). CONCLUSIONS: This scoping review provides an overview of the mutational landscape of PeM. Germline mutations might be a larger contributor to the incidence of PeM than previously thought. Currently available targeted therapy options are limited, but several targeted agents [such as poly (ADP-ribose) polymerase (PARP), enhancer of zeste homolog 2 (EZH2), and cyclin-dependent kinase 4/6 (CDK4/6) inhibitors] were identified that might provide new targeted therapy options in the future.
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Neoplasias Pulmonares , Mesotelioma Maligno , Mesotelioma , Neoplasias Peritoneales , Humanos , Neoplasias Pulmonares/genética , Mesotelioma Maligno/genética , Mesotelioma/genética , Mesotelioma/patología , Mutación , Neoplasias Peritoneales/genética , Neoplasias Peritoneales/patología , Secuenciación de Nucleótidos de Alto Rendimiento/métodosRESUMEN
Administration of azobenzenearsonate (ABA)-coupled syngeneic spleen cells intravenously to A/J mice leads to the generation of suppressor T cells (Ts1) which exhibit specific binding to ABA-bovine serum albumin (BSA)-coated dishes. These Ts1 share idiotypic determinants with the major cross-reactive idiotype (CRI) of the anti-ABA antibodies of A/J mice, and also produce a soluble suppressor factor (TsF) bearing CRI and I-J subregion-coded determinants. Injection of this TsF into naive A/J mice elicits a second set of specific suppressor cells (Ts2) which are not lysed by anti-CRI antibody plus C, and which do not bind to ABA-BSA-coated dishes. However, in contrast with Ts1, these Ts2 do bind to plates bearing CRI+ anti-ABA immunoglobulin. Thus, Ts2 exhibit anti-idiotypic specificity. These data indicate that antigen elicits the production of a soluble T cell product bearing both variable portion of the Ig heavy chain (VH) and I-J subregion-coded determinants which serves to communicate between T cell subsets to establish an idiotype-anti-idiotype regulatory pathway.
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Inmunidad Celular , Idiotipos de Inmunoglobulinas , Linfocinas/inmunología , Complejo Mayor de Histocompatibilidad , Receptores Inmunológicos , Linfocitos T Reguladores/inmunología , Animales , Anticuerpos Antiidiotipos , Antígenos de Superficie/análisis , Proteínas del Sistema Complemento/metabolismo , Citotoxicidad Inmunológica , Femenino , Hipersensibilidad Tardía/inmunología , Isoantígenos/análisis , Ratones , Linfocitos T/inmunologíaRESUMEN
The RFV strain of the Friend virus complex induces an erythroleukemia that spontaneously regresses. The tropism of regressing Friend virus complex (RFV), which is conferred by its helper MuLV component, MuLV-RF, is different from that of the conventional virus strain, CFV. RFV is NB-tropic and CFV is N-tropic. Passage of nonregressing CFV through Fv-1 incompatible Swiss/ICR mice changed the tropism of CFV from N to NB and resulted in a virus strain which induced erythroleukemia that regressed. Passage of NB-tropic CFV back through Fv-1 compatible mice maintained NB-tropism and regression. Altering the quantity or type of helper MuLV in RFV complex by addition of Ri-MuLV inhibited regression in proportion to the amount of added Ri-MuLV. These studies indicate a relationship between a change in virus tropism to NB by passage in certain hosts (e.g., Swiss/ICR mice) and the ability of Friend virus to induce erythroleukemia that spontaneously regresses. MuLV-RF isolated from the RFV complex induced lymphocytic leukemia in newborn mice which regressed and caused the regression of CFV-induced erythroleukemia. MuLV-RF is NB-tropic, contains no spleen focus-forming virus (SFFV) activity and helps SFFV form spleen foci in genetically restrictive mice. Pseudotype viruses were prepared, consisting of MuLV-RF, or other MuLV's, and SFFV derived from FV-B. The pseudotype viruses each acquired the tropism of the MuLV used in rescue. The pseudotype prepared with MuLV-RF or another NB-tropic MuLV-F, but not the virus obtained by rescue with N-tropic MuLV-F, induced erythroleukemia that spontaneously regressed. These studies demonstrate that the ability of RFV to induce erythroleukemia that spontaneously regresses is due to its helper MuLV component.
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Virus de la Leucemia Murina de Friend/fisiología , Virus Helper/fisiología , Leucemia Eritroblástica Aguda/microbiología , Regresión Neoplásica Espontánea , Animales , Virus de la Leucemia Murina de Friend/aislamiento & purificación , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos ICRRESUMEN
A/J anti-p-azobenzenearsonate (ABA) antibodies bearing cross-reactive idiotypic (CRI) determinants, when coupled to spleen cells and then injected intravenously into naive animals, stimulate suppressor T cell (Ts) responses. Moreover, previous studies have demonstrated that the ability of such idiotype-coupled spleen cells to induce immune unresponsiveness to subsequent immunization with ABA-coupled spleen cells is linked to Igh-1 genes. Thus, CRI bearing antibodies from A/J mice, when conjugated to normal BALB/c spleen cells in vitro and then injected intravenously to syngeneic BALB/c mice, failed to induce tolerance in these animals. However, spleen cells taken from these animals transferred significant degrees of suppression to Igh-1 congenic C.AL-20 but not to H-2 congenic, Igh-1 distinct B10.D2 mice. Therefore, the failure of CRI-coupled spleen cells to induce suppressor cell- mediated unresponsiveness in animals unable to express the appropriate VH genes (i.e. BALB/c and B10.D2) appears to be caused by the lack of idiotype- matched targets. The notion that the ability to express certain Vn genes in the recipient animal is a prerequisite for suppressor cell function was further supported by the observation that suppressor cells induced in C.AL-20 mice failed to transfer any degree of suppression to BALB/c mice. The ability to transfer suppression from BALB/c mice to C.AL-20 mice is a T cell- dependent phenomenon, since in vitro treatment with anti-Thy 1.2 antiserum and complement completely abrogated suppressor cell function. Furthermore, these suppressor T cells are antigen specific and can be enriched on idiotype-coated petri dishes, indicating they possess anti-idiotypic receptors. Therefore, appropriate anti-idiotype and idiotype interaction is essential for the manifestation of suppressor T cell function in ABA-specific suppressor pathways.
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Epítopos/genética , Genes MHC Clase II , Idiotipos de Inmunoglobulinas/inmunología , Linfocitos T/inmunología , Animales , Reacciones Cruzadas , Femenino , Hipersensibilidad Tardía/inmunología , Ratones , Ratones Endogámicos BALB C , Bazo/citología , Linfocitos T Reguladores/inmunologíaRESUMEN
Azobenzenearsonate (ABA)-specific T cell-derived suppressor factor (TsF1) from A/J mice was used to induced second-order suppressor T cells (Ts2). Comparison of suppressor T cells induced by antigen (Ts1) with Ts2 induced by TsF1 revealed that Ts1 were afferent suppressors active only when given at the time of antigen priming, and not thereafter, whereas Ts2 could act when transferred at any time up to 1 d before antigen challenge for a delayed-type hypersensitivity response. This was true even when the recipient could be shown to be fully immune before transfer of Ts2, thus defining these cells as efferent suppressors. The anti-idiotypic specificity of the Ts2 was demonstrated by the ability of Ts to bind to idiotype (cross-reactive idiotype [CRI])-coated Petri dishes. A soluble extract from Ts2 (TsF2) was also capable of mediating efferent suppression that was functionally antigen- (ABA) specific. Comparison of TsF1 with this new factor, TsF2, revealed that both lack Ig-constant-region determinants, possess H-2-coded determinants, and show specific binding (to ABA and to CRI+-Ig, respectively). TsF1 acts in strains that differ with respect to H-2 and background genes, whereas TsF2 shows H-2- and non-H-2-linked genetic restrictions. This existence of H-2 restriction of TsF2 activity suggests that the apparent discrepancies in studies of H-2 restriction of TsF may be a result of the analysis of two separate classes of TsF, only one of which shows genetically restricted activity, thus unifying several models of suppressor cell activity.
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Antígenos H-2 , Idiotipos de Inmunoglobulinas , Linfocinas/biosíntesis , Receptores Inmunológicos , Animales , Fenómenos Químicos , Química , Reacciones Cruzadas , Epítopos , Hipersensibilidad Tardía/inmunología , Ratones , Ratones Endogámicos A , Biosíntesis de Proteínas , Factores Supresores Inmunológicos , Factores de Tiempo , p-Azobencenoarsonato/inmunologíaRESUMEN
Human rIL-2 (10-30 micrograms) was injected intradermally into the skin of patients with lepromatous leprosy with high bacillary loads. All patients responded to the lymphokine with local areas of induration that peaked at 24 h and persisted for 4-7 d irrespective of whether the site was "normal skin" or a nodular lesion. Within 24 h there was an extensive emigration of T cells and monocytes into the site. The percentage of the dermis infiltrated by mononuclear cells increased by more than sevenfold, peaking at 4 d and persisting for greater than 15 d. Both CD4+ and CD8+ T cells entered the site. T cells of CD4+ phenotype predominated at 2-7 d but by 11 d, CD8+ cells were predominant. Considerable numbers of T6+ Langerhans' cells appeared in the dermis by 72 h and persisted for 3 wk. By 4 d the thickness of the overlying epidermis had increased twofold, and keratinocytes were expressing MHC class II antigen and the IFN-gamma-induced peptide IP-10. Starting at 48 h, there was an extensive destruction of mononuclear phagocytes that contained structurally intact or fragmented M. leprae observed at the electron microscope level. The organisms, either free or contained within endocytic vacuoles, were discharged into the extracellular space and then reingested by blood-borne monocytes. This was followed by marked reductions in the number of acid-fast organisms in the injected site, evident as early as 4-7 d and more marked at 2-3 wk after injection. 13 of 15 patients exhibited a disposal of acid-fast bacilli ranging from 5- to 1,000-fold with a mean value of approximately 100-fold. The administration of IL-2 leads to the generation of an effective cell-mediated immune response, recapitulating an antigen-driven event and leading to striking local reductions in M. leprae. In comparison with the purified protein derivative of tuberculin reaction, bacilli are cleared more promptly, although emigratory cells persist for a shorter time.
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Interleucina-2/farmacología , Lepra Lepromatosa/inmunología , Piel/inmunología , Adulto , Antígenos de Diferenciación de Linfocitos T/análisis , Antígenos CD8 , Diferenciación Celular , Epidermis/patología , Humanos , Inmunidad Celular , Células de Langerhans/patología , Lepra Lepromatosa/microbiología , Lepra Lepromatosa/patología , Leucocitos Mononucleares/patología , Macrófagos/patología , Microscopía Electrónica , Persona de Mediana Edad , Mycobacterium leprae/aislamiento & purificación , Fagocitos/patología , Proteínas Recombinantes/farmacología , Piel/microbiología , Piel/patología , Linfocitos T/inmunología , Linfocitos T/patologíaRESUMEN
The synaptic basal lamina, a component of extracellular matrix (ECM) in the synaptic cleft at the neuromuscular junction, directs the formation of new postsynaptic specializations, including the aggregation of acetylcholine receptors (AChRs), during muscle regeneration in adult animals. Although the molecular basis of this phenomenon is unknown, it is mimicked by AChR-aggregating proteins in ECM-enriched fractions from muscle and the synapse-rich electric organ of the ray Torpedo californica. Molecules immunologically similar to these proteins are concentrated in the synaptic basal lamina at neuromuscular junctions of the ray and frog. Here we demonstrate that immunologically, chemically, and functionally similar AChR-aggregating proteins are also associated with the ECM of several other tissues in Torpedo. Monoclonal antibodies against the AChR-aggregating proteins from electric organ intensely stained neuromuscular junctions and the ventral surfaces of electrocytes, structures with a high density of AChRs. However, they also labeled many other structures which have basal laminae, including the extrajunctional perimeters of skeletal muscle fibers, smooth and cardiac muscle cells, Schwann cell sheaths in peripheral nerves, walls of some blood vessels, and epithelial basement membranes in the gut, skin, and heart. Some structures with basal laminae did not stain with the antibodies; e.g., the dorsal surfaces of electrocytes. Bands of similar molecular weight were detected by the antibodies on Western blots of extracts of ECM-enriched fractions from electric organ and several other tissues. Proteins from all tissues examined, enriched from these extracts by affinity chromatography with the monoclonal antibodies, aggregated AChRs on cultured myotubes. Thus, similar AChR-aggregating proteins are associated with the extracellular matrix of many Torpedo tissues. The broad distribution of these proteins suggests they have functions in addition to AChR aggregation.
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Matriz Extracelular/análisis , Proteínas del Tejido Nervioso/análisis , Proteínas/análisis , Receptores Colinérgicos/metabolismo , Agrina , Animales , Anticuerpos Monoclonales , Antígenos/análisis , Antígenos/inmunología , Membrana Basal/análisis , Cromatografía de Afinidad , Técnica del Anticuerpo Fluorescente , Inmunoensayo , Proteínas del Tejido Nervioso/inmunología , Unión Neuromuscular/análisis , Proteínas/inmunología , Agregación de Receptores , TorpedoRESUMEN
Myoinositol kinase found in plant, animal, and microbial extracts has been partially purified by densitygradient centrifugation. The product of the enzymic reaction has been tentatively identified by paper chromatography. as myoinositol-1-phosphate.
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Fosfotransferasas , Isótopos de Carbono , Centrifugación , Cromatografía en Papel , Inositol , Fosfatos , Plantas Comestibles , Radiometría , Semillas , TriticumRESUMEN
To evaluate the role of immune response in regression of leukemia, we studied the effect of immunosuppression on the spontaneous regression of a leukemia induced by a specific strain of Friend murine leukemia virus complex (RFV). Thymectomy of newborn but not adult outbred Swiss mice markedly inhibited regression. The effect of antithymocyte serum (ATS) on regression depended on the timing of ATS treatment. Regression was markedly inhibited in leukemic mice given ATS just before the start of regression. During leukemia development, ATS treatment but not thymectomy potentiated splenomegaly and delayed the start of regression. Both ATS treatment and neonatal thymectomy increased mortality as a function of the decrease in disease regression. Treatment with normal rabbit serum also inhibited regression but, when given during leukemia development, affected neither the splenomegalic response to RFV nor the number of deaths. The data demonstrated that an intact immune system was required for leukemia regression and suggested that some thymus-dependent parameter of immune response was a major factor in regression.
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Terapia de Inmunosupresión , Leucemia Eritroblástica Aguda/inmunología , Regresión Neoplásica Espontánea , Linfocitos T/inmunología , Animales , Formación de Anticuerpos , Suero Antilinfocítico/farmacología , Virus de la Leucemia Murina de Friend , Leucemia Eritroblástica Aguda/etiología , Leucemia Eritroblástica Aguda/patología , Ratones , Ratones Endogámicos DBA , Remisión Espontánea , Timo/inmunologíaRESUMEN
We characterized several aspects of spontaneous regression of lymphocytic leukemia in mice. The disease, induced by the helper murine leukemia virus (MuLV) component obtained from the regressing Friend virus complex (RFV), was characterized by spleen and lymph node enlargement, thymus involvement, and anemia. Leukemia regression occurred in about 25% of infected mice and resulted in the return of lymphoid organs to near-normal weight and normal histology and the recovery from anemia. A tenfold to 1,000-fold decrease in virus titer was seen in those mice in which leukemia regressed when compared to leukemic animals, although infectious virus was still recoverable from apparently normal spleens. The sera of mice in which leukemia regressed contained potent virus-neutralizing activity that was associated mainly with immunoglobulins. These studies firmly supported the evidence that the regressing phenotype of RFV was due to its helper MuLV component (MuLV-RF).
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Virus de la Leucemia Murina de Friend , Leucemia Experimental/patología , Regresión Neoplásica Espontánea , Animales , Anticuerpos Antivirales , Femenino , Virus de la Leucemia Murina de Friend/inmunología , Virus Helper/inmunología , Virus de la Leucemia Murina/inmunología , Leucemia Eritroblástica Aguda/inmunología , Leucemia Experimental/inmunología , Leucemia Linfoide/inmunología , Leucemia Linfoide/patología , Masculino , Ratones , Ratones Endogámicos , Especificidad de la Especie , Infecciones Tumorales por Virus/patologíaRESUMEN
The spontaneous regression of the erythroleukemia induced by the regressing Friend murine leukemia virus (F-MuLV) complex was inhibited by irradiation of the animals prior to F-MuLV inoculation. This inhibition was proportional to the dose of radiation used. Treatment of the mice with the bone-seeking isotope 89Sr also inhibited erythroleukemia regression, which implicates the same effector mechanisms involved in the resistance to F-MuLV or F-MuLV-induced immunosuprression. Erythroleukemias induced in athymic nude mice by the regressing F-MuLV complex exhibited higher rates of lethality than did the leukemias in heterozygous or homozygous thymus gland-containing controls. These data suggested the involvement of the immune system in erythroleukemia regression and the specific participation of thymus cells and an 89Sr-susceptible function, perhaps marrow-dependent cells, in the process of regression.
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Inmunidad , Leucemia Experimental/inmunología , Regresión Neoplásica Espontánea , Infecciones Tumorales por Virus/inmunología , Animales , Virus de la Leucemia Murina de Friend , Inmunidad/efectos de la radiación , Terapia de Inmunosupresión , Leucemia Eritroblástica Aguda/inmunología , Masculino , Ratones , Ratones Desnudos , Radioisótopos de EstroncioRESUMEN
We discovered that skilled nurses only casually trained in the use of a fingertip blood glucose reflectance meter (Glucoscan, Lifescan, Mountainview, California) had a 36% incidence of unacceptable results (greater than 15% from reference). A controlled study was undertaken and showed that with Glucoscan I (GI) 4 of 27 readings were unacceptable and with Glucoscan II (GII) 3 of 27 readings were unacceptable, a statistically nonsignificant difference. Minor deviations from the manufacturer's recommended technique had a significant effect on the results with GI. In contrast, GII was much less sensitive to variations in recommended technique. GI underestimated the reference glucose concentration by 11.7%, and GII overestimated by 6.5%, a statistically significant difference. We conclude that the health professional must be aware of interdevice and intradevice variability in self-monitoring of blood glucose (SMBG). Patients need careful training in the method of SMBG. The results of any single value should be interpreted with caution.
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Análisis Químico de la Sangre/instrumentación , Glucemia/análisis , Diabetes Mellitus Tipo 1/sangre , Sistemas de Infusión de Insulina , Autocuidado/instrumentación , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Humanos , Estudios ProspectivosRESUMEN
The effects of light on the circadian pacemaker in the suprachiasmatic nucleus (SCN) are mediated by the retinohypothalamic tract (RHT) and by the retinogeniculosuprachiasmatic tract (RGST). The neurotransmitter of the RGST is neuropeptide Y. The RHT may contain glutamate and aspartate. Recent evidence indicates that acetylcholine could also be involved in phase shifting by light. We determined that intraventricular injections with an acetylcholine agonist, carbachol, induces phase advances during the subjective day and phase delays during the early subjective night. No differences were observed between phase shifts induced in constant darkness and those induced in continuous light. A dose-response curve for carbachol was described at circadian time 6 (CT6). Injections at CT14 with various dosages of carbachol indicated the same dose dependency for this circadian time. Finally, carbachol injections in split animals resulted in similar responses of the two components of the split activity rhythm.
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Carbacol/farmacología , Ritmo Circadiano/fisiología , Actividad Motora/efectos de los fármacos , Animales , Carbacol/administración & dosificación , Ritmo Circadiano/efectos de los fármacos , Cricetinae , Inyecciones Intraventriculares , Masculino , MesocricetusRESUMEN
OBJECTIVE: Parameters of a pharmacokinetic-pharmacodynamic (PK-PD) model of levodopa have been claimed to reflect the magnitude of the dopaminergic deficit in patients with Parkinson's disease. The aim of this study was to correlate such parameters with positron emission tomography (PET) with levodopa tagged with 6-fluorine 18, an established imaging method for striatal dopaminergic neurons. METHODS: Twenty-three patients in different disease stages (Hoehm and Yahr stage 2.5-5 [Hoehn MM, Yahr MD. Parkinsonism: onset, progression and mortality. Neurology 1967;4:427-42]; median duration, 12 years) were studied. PK-PD modeling followed a single oral dose of levodopa/benserazide. The sum score of the Columbia Rating Scale (CURSSigma) was used for clinical assessments. A nonparametric effect compartment approach assuming a sigmoidal E(max) model was applied to the PK-PD analysis of plasma levodopa concentrations and corresponding CURSSigma. Thereafter 6-[18F]levodopa PET was performed, and the influx rate constants (k(c)) for the putamen and the caudatus region were correlated with the median effective concentration (EC(50)) and the equilibrium half-life (T(eq)) of the PK-PD model. RESULTS: (1) A significant correlation was observed between PK-PD parameters or with k(c) putamen as the dependent variable and the duration of the disease as the independent variable, which explains 33% of the variability of the EC(50), 42% of the variability of T(eq), and 36% of the variability of k(c). (2) Significant correlations were observed between k(c) and either EC(50) or T(eq), yielding the closest correlation for the putamen region (r = -0.47, P <.05; and r = 0.55, P <.01; respectively). CONCLUSIONS: Our findings show that key parameters of a PK-PD model of levodopa were in fairly close agreement with imaging of dopaminergic neurons by 6-[18F]levodopa PET. However, although PK-PD modeling of levodopa has been proven as a useful investigation of approaches aimed to restore dopaminergic deficits or to monitor disease progression, this modeling cannot serve as a pathomorphologic surrogate for the loss of striatal dopaminergic neurons.
Asunto(s)
Antiparkinsonianos/farmacocinética , Cuerpo Estriado/diagnóstico por imagen , Cuerpo Estriado/metabolismo , Dopaminérgicos/farmacocinética , Levodopa/metabolismo , Enfermedad de Parkinson/diagnóstico por imagen , Enfermedad de Parkinson/metabolismo , Tomografía Computarizada de Emisión , Adulto , Anciano , Antiparkinsonianos/administración & dosificación , Antiparkinsonianos/sangre , Antiparkinsonianos/metabolismo , Núcleo Caudado/diagnóstico por imagen , Núcleo Caudado/metabolismo , Cromatografía Líquida de Alta Presión , Dopaminérgicos/administración & dosificación , Dopaminérgicos/sangre , Dopaminérgicos/metabolismo , Femenino , Radioisótopos de Flúor , Semivida , Humanos , Levodopa/sangre , Modelos Lineales , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/sangre , Enfermedad de Parkinson/diagnóstico , Putamen/diagnóstico por imagen , Putamen/metabolismo , Índice de Severidad de la Enfermedad , Tomografía Computarizada de Emisión/métodosRESUMEN
Glutethimide has been used to control essential tremor. Its efficacy in the treatment of disabling cerebellar and rubral tremor was assessed in an open study of six patients with multiple sclerosis and two patients with traumatic brain injury. Functional and quantitative tremor severity was assessed before treatment and 7 to 14 days after a stable dose was achieved. Six of eight patients exhibited visible functional benefit from treatment with glutethimide; abstract testing results correlated well with functional status in most cases. Four patients chose to continue to receive medication. Controlled trials of glutethimide to compare its efficacy with that of other medications used in the treatment of action tremor are indicated.
Asunto(s)
Lesiones Encefálicas/complicaciones , Glutetimida/uso terapéutico , Esclerosis Múltiple/complicaciones , Temblor/tratamiento farmacológico , Humanos , Temblor/etiología , Temblor/fisiopatologíaRESUMEN
We examined the toxicity of both single and multiple subcutaneous injections of recombinant human ciliary neurotrophic factor (rhCNTF) in 72 patients with ALS, in doses ranging from 2 to 100 micrograms/kg. Adverse events were generally dose related and ranged from mild to severe. The tolerability of daily subcutaneous rhCNTF was equivalent to placebo at doses < or = 5 micrograms/kg/day. At higher doses, anorexia, weight loss, reactivation of herpes simplex virus (HSV1) labialis/stomatitis, cough, and increased oral secretions occurred.