RESUMEN
Branchial arches are embryologic structures that develop between the fourth and seventh gestational week. Anomalies may form if these structures fail to develop. The majority of cases are diagnosed during childhood, with surgical excision recommended to prevent risk of infection, growth or malignancy. We report an unusual case of a 72-year-old man with severe cardiac comorbidities who presented with a large second branchial arch cyst extending into the oropharynx. General anaesthesia to facilitate surgical excision was deemed too risky. Therefore, we performed successful ultrasound-guided superficial and deep cervical plexus blocks as a sole mode of anaesthesia. This case highlights how regional anaesthesia can be utilised to facilitate surgery in high-risk patients, as well as presenting an alternative for general anaesthesia.
RESUMEN
BACKGROUND: Randomised trial protocols may incorporate interim analyses, with the potential to stop the study for futility if early data show insufficient promise of a treatment benefit. Previously, we have shown that this approach will theoretically lead to mis-estimation of the treatment effect. We now wished to ascertain the importance of this phenomenon in practice. METHODS: We reviewed the methods and results in a set of trials that had stopped for futility, identified through an extensive literature search. We recorded clinical areas, interventions, study design, outcomes, trial setting, sponsorship, planned and actual treatment effects, sample sizes; power; and if there was a data safety monitoring board, or a published protocol. We identified: if interim analyses were pre-specified, and how many analyses actually occurred; what pre-specified criteria might define futility; if a futility analysis formed the basis for stopping; who made the decision to stop; and the conditional power of each study, i.e. the probability of statistically significant results if the study were to continue to its complete sample size. RESULTS: We identified 52 eligible trials, covering many clinical areas. Most trials had multiple centres, tested drugs, and 40% were industry sponsored. There were 75% where at least one interim analysis was planned a priori; a majority had only one interim analysis, typically with about half the target total sample size. A majority of trials did not pre-define a stopping rule, and a variety of reasons were given for stopping. Few studies calculated and reported low conditional power to justify the early stop. When conditional power could be calculated, it was typically low, especially under the current trend hypothesis. However, under the original design hypothesis, a few studies had relatively high conditional power. Data collection often continued after the interim analysis. CONCLUSIONS: Although other factors will typically be involved, we conclude that, from the perspective of conditional power, stopping early for futility was probably reasonable in most cases, but documentation of the basis for stopping was often missing or vague. Interpretation of truncated trials would be enhanced by improved reporting of stopping protocols, and of their actual execution.
Asunto(s)
Inutilidad Médica , Ensayos Clínicos Controlados Aleatorios como Asunto/estadística & datos numéricos , Privación de Tratamiento/estadística & datos numéricos , Análisis de Datos , Humanos , Proyectos de Investigación , Insuficiencia del TratamientoRESUMEN
OBJECTIVES: To establish the current use of granulocyte transfusions in haematology patients and explore interest in further research. BACKGROUND: Granulocytes may be used for the treatment of severe infection in neutropenic patients or for primary or secondary prophylaxis. Clinical utility of granulocyte transfusions is unclear, and recent studies have demonstrated equivocal outcomes. Pooled granulocytes are the main granulocyte product used in England and Wales, but there are no data on the patterns of use and little consensus on accepted indications. METHODS: A survey was distributed to UK hospitals delivering intensive chemotherapy. Clinical scenarios were posed, with further questions on clinician experience of using granulocytes, availability of the product, barriers to use and interest in further research. RESULTS: The response rate was 57%; 34·9% of all responses were from allogeneic stem cell transplant centres. Paediatric centres comprised 9·5% respondents, and 19% centres had access to apheresis granulocytes. Of respondents, 58·7% had used granulocytes in the last 3 years, 89·2% of whom used granulocytes to treat refractory infection. There was little consensus on use of granulocytes in the given clinical scenarios even when patients clearly met national guideline criteria. Paediatric centres were overall more likely to recommend granulocyte use. The most frequently identified barrier to use of granulocytes was lack of evidence of effect. Of the respondents, 75% indicated a willingness to participate in further research. CONCLUSION: There remains a lack of consistency about use of granulocytes, which is unsurprising given the lack of clinical data to support their efficacy. We did, however, demonstrate a willingness to participate in further research.
Asunto(s)
Granulocitos , Transfusión de Leucocitos , Neutropenia/epidemiología , Neutropenia/terapia , Inglaterra/epidemiología , Femenino , Humanos , Masculino , Gales/epidemiologíaRESUMEN
Immune senescence as well as disturbed CD8+ T cell differentiation are a hallmark of chronic HIV infection. Here, we investigated to what extent immune senescence is reversible after initiation of anti-retroviral treatment (ART). Peripheral blood mononuclear cells (PBMCs) from a cohort of HIV patients with different disease courses, including untreated viral controllers (n = 10), viral non-controllers (n = 16) and patients on ART (n = 20), were analysed and compared to uninfected controls (n = 25) by flow cytometry on bulk and HIV-specific major histocompatibility complex (MHC) class I tetramer+ CD8+ T cells for expression of the memory markers CCR7 and CD45RO, as well as the senescence marker CD57 and the differentiation and survival marker CD127. Furthermore, a subset of patients was analysed longitudinally before and after initiation of ART. Frequencies of CD57+ CD8+ T cells decreased after initiation of ART in central memory (Tcm) but not in effector memory T cell populations (TemRO and TemRA). The frequency of CD127+ CD8+ cells increased in Tcm and TemRO. We observed a reduction of CD127- T cells in Tcm, TemRO and partially in TemRA subsets after initiation of ART. Importantly, HIV-specific CD8+ TemRO cells predominantly displayed a CD127- CD57+ phenotype in untreated HIV-patients, whereas the CD127+ CD57- phenotype was under-represented in these patients. The frequency of the CD127+ CD57- CD8+ T cell subpopulation correlated strongly with absolute CD4+ counts in HIV-infected patients before and after initiation of ART. These findings can be interpreted as a phenotypical correlate of CD8+ memory T cell differentiation and the premature 'ageing' of the immune system, which was even observed in successfully virally suppressed HIV patients.
Asunto(s)
Linfocitos T CD8-positivos/inmunología , Diferenciación Celular , Infecciones por VIH/inmunología , Infecciones por VIH/virología , VIH-1/inmunología , Memoria Inmunológica , Antígenos CD/metabolismo , Antígenos Virales/inmunología , Terapia Antirretroviral Altamente Activa , Recuento de Linfocito CD4 , Linfocitos T CD8-positivos/citología , Linfocitos T CD8-positivos/metabolismo , Estudios de Casos y Controles , Diferenciación Celular/inmunología , Epítopos de Linfocito T/inmunología , Infecciones por VIH/tratamiento farmacológico , Humanos , Inmunofenotipificación , Recuento de LinfocitosRESUMEN
The crizotinib-resistant ALK(F1174L) mutation arises de novo in neuroblastoma (NB) and is acquired in ALK translocation-driven cancers, lending impetus to the development of novel anaplastic lymphoma kinase (ALK) inhibitors with different modes of action. The diaminopyrimidine TAE684 and its derivative ceritinib (LDK378), which are structurally distinct from crizotinib, are active against NB cells expressing ALK(F1174L). Here we demonstrate acquired resistance to TAE684 and LDK378 in ALK(F1174L)-driven human NB cells that is linked to overexpression and activation of the AXL tyrosine kinase and epithelial-to-mesenchymal transition (EMT). AXL phosphorylation conferred TAE684 resistance to NB cells through upregulated extracellular signal-regulated kinase (ERK) signaling. Inhibition of AXL partly rescued TAE684 resistance, resensitizing these cells to this compound. AXL activation in resistant cells was mediated through increased expression of the active form of its ligand, GAS6, that also served to stabilize the AXL protein. Although ectopic expression of AXL and TWIST2 individually in TAE684-sensitive parental cells led to the elevated expression of mesenchymal markers and invasive capacity, only AXL overexpression induced resistance to TAE684 as well. TAE684-resistant cells showed greater sensitivity to HSP90 inhibition than did their parental counterparts, with downregulation of AXL and AXL-mediated ERK signaling. Our studies indicate that aberrant AXL signaling and development of an EMT phenotype underlie resistance of ALK(F1174L)-driven NB cells to TAE684 and its derivatives. We suggest that the combination of ALK and AXL or HSP90 inhibitors be considered to delay the emergence of such resistance.
Asunto(s)
Resistencia a Antineoplásicos/genética , Transición Epitelial-Mesenquimal/genética , Mutación , Proteínas Proto-Oncogénicas/genética , Proteínas Tirosina Quinasas Receptoras/genética , Quinasa de Linfoma Anaplásico , Western Blotting , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Crizotinib , Activación Enzimática/efectos de los fármacos , Transición Epitelial-Mesenquimal/efectos de los fármacos , Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Inmunohistoquímica , Neuroblastoma/genética , Neuroblastoma/metabolismo , Neuroblastoma/patología , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas/metabolismo , Pirazoles/farmacología , Piridinas/farmacología , Pirimidinas/farmacología , Interferencia de ARN , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Proteínas Tirosina Quinasas Receptoras/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sulfonas/farmacología , Tirosina Quinasa del Receptor AxlRESUMEN
OBJECTIVE: Socio economic status is an important determinant of health and disease in population. Various scales for measuring the same exist in modern Indian society each with it's own limitations. Present study was done to abridge the existing and latest available Aggarwal Scale. STUDY DESIGN: Cross Sectional Study. MATERIAL AND METHODS: All relevant information pertaining to Aggarwal et al scale was collected for 197 households and analyzed in SPSS 16. Data reduction was done using Factor Analysis (FA) under which Principal Components Analysis (PCA) was used. RESULTS: Four components were selected based on criteria Eigen value of more than one and elbowing in scree plot. All the 22 items of Aggarwal et al were divided among these 4 components. Based on factor loadings four reduced scales were constructed. Percentage agreement of reduced scales with original scale increased as we increased the number of items in the scale. Analysis narrowed down the 22 items of Aggarwal et al scale to six items e.g. locality, education of husband/ wife, occupation of husband/ wife, family possessions, caste and monthly per capita income. These 6 items together accounted for 49% of the variation and can be taken as a surrogate measure of SES of the family. CONCLUSION: We have presented reduced versions of Aggarwal et al scale along with degree of agreement with the original scale. Authors propose the use of these scales to measure SES to overcome the time constraint in practicing research.
Asunto(s)
Investigación Participativa Basada en la Comunidad , Clase Social , Población Urbana , Estudios Transversales , Composición Familiar , Humanos , India , Análisis de Componente Principal , Factores SocioeconómicosRESUMEN
BACKGROUND: To investigate prognosis and effects of first-line therapy in elderly primary central nervous system lymphoma (PCNSL) patients. PATIENTS AND METHODS: A systematic review of studies about first-line therapy in immunocompetent patients ≥60 years with PCNSL until 2014 and a meta-analysis of individual patient data from eligible studies and international collaborators were carried out. RESULTS: We identified 20 eligible studies; from 13 studies, we obtained individual data of 405 patients, which were pooled with data of 378 additional patients (N = 783). Median age and Karnofsky Performance Score (KPS) was 68 years (range: 60-90 years) and 60% (range: 10%-100%), respectively. Treatments varied greatly, 573 (73%) patients received high-dose methotrexate (HD-MTX)-based therapy. A total of 276 patients received whole-brain radiotherapy (median 36 Gy, range 28.5-70 Gy). KPS ≥ 70% was the strongest prognostic factor for mortality [hazard ratio (HR) 0.50, 95% confidence interval (CI) 0.41-0.62]. After a median follow-up of 40 months, HD-MTX-based therapy was associated with improved survival (HR 0.70, 95% CI 0.53-0.93). There was no difference between HD-MTX plus oral chemotherapy and more aggressive HD-MTX-based therapies (HR 1.39, 95% CI 0.90-2.15). Radiotherapy was associated with an improved survival, but correlated with an increased risk for neurological side-effects (odds ratio 5.23, 95% CI 2.33-11.74). CONCLUSIONS: Elderly PCNSL patients benefit from HD-MTX-based therapy, especially if combined with oral alkylating agents. More aggressive HD-MTX protocols do not seem to improve outcome. WBRT may improve outcome, but is associated with increased risk for neurological side-effects. Prospective trials for elderly PCNSL patients are warranted.
Asunto(s)
Antimetabolitos Antineoplásicos/uso terapéutico , Neoplasias del Sistema Nervioso Central/tratamiento farmacológico , Linfoma/tratamiento farmacológico , Metotrexato/uso terapéutico , Anciano , Neoplasias del Sistema Nervioso Central/mortalidad , Humanos , Linfoma/mortalidad , Pronóstico , Tasa de SupervivenciaRESUMEN
Heterozygous germline mutations in PHOX2B, a transcriptional regulator of sympathetic neuronal differentiation, predispose to diseases of the sympathetic nervous system, including neuroblastoma and congenital central hypoventilation syndrome (CCHS). Although the PHOX2B variants in CCHS largely involve expansions of the second polyalanine repeat within the C-terminus of the protein, those associated with neuroblastic tumors are nearly always frameshift and truncation mutations. To test the hypothesis that the neuroblastoma-associated variants exert their effects through loss or gain of protein-protein interactions, we performed a large-scale yeast two-hybrid screen using both wild-type (WT) and six different mutant PHOX2B proteins against over 10 000 human genes. The neuronal calcium sensor protein HPCAL1 (VILIP-3) exhibited strong binding to WT PHOX2B and a CCHS-associated polyalanine expansion mutant but only weakly or not at all to neuroblastoma-associated frameshift and truncation variants. We demonstrate that both WT PHOX2B and the neuroblastoma-associated R100L missense and the CCHS-associated alanine expansion variants induce nuclear translocation of HPCAL1 in a Ca(2+)-independent manner, while the neuroblastoma-associated 676delG frameshift and K155X truncation mutants impair subcellular localization of HPCAL1, causing it to remain in the cytoplasm. HPCAL1 did not appreciably influence the ability of WT PHOX2B to transactivate the DBH promoter, nor did it alter the decreased transactivation potential of PHOX2B variants in 293T cells. Abrogation of the PHOX2B-HPCAL1 interaction by shRNA knockdown of HPCAL1 in neuroblastoma cells expressing PHOX2B led to impaired neurite outgrowth with transcriptional profiles indicative of inhibited sympathetic neuronal differentiation. Our results suggest that certain PHOX2B variants associated with neuroblastoma pathogenesis, because of their inability to bind to key interacting proteins such as HPCAL1, may predispose to this malignancy by impeding the differentiation of immature sympathetic neurons.
Asunto(s)
Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Mutación , Neuroblastoma/genética , Neuroblastoma/metabolismo , Neurocalcina/genética , Neurocalcina/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Calcio/metabolismo , Diferenciación Celular/genética , Línea Celular , Línea Celular Tumoral , Núcleo Celular/genética , Núcleo Celular/metabolismo , Citoplasma/genética , Citoplasma/metabolismo , Células HEK293 , Humanos , Neuroblastoma/patología , Péptidos/genética , Péptidos/metabolismo , Regiones Promotoras Genéticas , Unión Proteica , Mapas de Interacción de Proteínas , Activación TranscripcionalRESUMEN
The goal of this study was to understand how immune reconstitution through ART in HIV-1 infected patients affects CD4(+) recent thymic emigrants (identified as CD31(+) naïve T cells). We performed FACS analysis of CD4(+) CD31(+) naïve T cells from PBMCs in a cross-sectional age-matched cohort, including 25 healthy controls (HC), 18 untreated HIV-1 infected viremic progressors (VP), 10 untreated HIV-1 infected viral controllers (VC), and 24 HIV-1 infected immune responders (IR) following ART. Our data reveal that 37.5% of IR failed to restore their CD4(+) CD31(+) naïve T cell counts. In addition, significantly higher expressions of Ki67, CD57, and CD95 were observed in CD4(+) CD31(+) naïve T cells of both VP and IR comparing to HC and VC. The significantly elevated CD57 and CD95 expressions are observed in IR with low CD4(+) CD31(+) naïve T cell counts. Therefore, our data indicate an incomplete immune reconstitution of CD4(+) CD31(+) naïve T cells in more than one third of IR, which is associated with HIV-1 driven immunological phenotypic alterations.
Asunto(s)
Antirretrovirales/uso terapéutico , Biomarcadores Farmacológicos/metabolismo , Linfocitos T CD4-Positivos/efectos de los fármacos , Antígenos CD57/metabolismo , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/inmunología , VIH-1/inmunología , Subgrupos de Linfocitos T/efectos de los fármacos , Receptor fas/metabolismo , Adulto , Anciano , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/virología , Antígenos CD57/genética , Estudios Transversales , Progresión de la Enfermedad , Femenino , Humanos , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/metabolismo , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/virología , Timo/inmunología , Regulación hacia Arriba , Receptor fas/genéticaAsunto(s)
Deficiencia de Ácido Fólico/complicaciones , Pancitopenia/etiología , Adulto , Transfusión Sanguínea , Médula Ósea/patología , Dieta , Disnea/etiología , Índices de Eritrocitos , Conducta Alimentaria , Fiebre/etiología , Ácido Fólico/uso terapéutico , Deficiencia de Ácido Fólico/tratamiento farmacológico , Humanos , Masculino , Pancitopenia/patología , Pancitopenia/terapiaRESUMEN
Advanced prostate cancers are known to acquire not only invasive capabilities but also significant resistance to chemotherapy-induced apoptosis. To understand how microRNAs (miRNAs) may contribute to prostate cancer resistance to apoptosis, we compared microRNA expression profiles of a benign prostate cancer cell line WPE1-NA22 and a highly malignant WPE1-NB26 cell line (derived from a common lineage). We found that miR-205 and miR-31 are significantly downregulated in WPE1-NB26 cells, as well as in other cell lines representing advanced-stage prostate cancers. Antiapoptotic genes BCL2L2 (encoding Bcl-w) and E2F6 are identified as the targets of miR-205 and miR-31, respectively. By downregulating Bcl-w and E2F6, miR-205 and miR-31 promote chemotherapeutic agents-induced apoptosis in prostate cancer cells. The promoter region of the miR-205 gene was cloned and was found to be hypermethylated in cell lines derived from advanced prostate cancers, contributing to the downregulation of the gene. Treatment with DNA methylation inhibitor 5-aza-2'-deoxycytidine induced miR-205 expression, downregulated Bcl-w, and sensitized prostate cancer cells to chemotherapy-induced apoptosis. Thus, downregulation of miR-205 and miR-31 has an important role in apoptosis resistance in advanced prostate cancer.
Asunto(s)
Apoptosis/efectos de los fármacos , Resistencia a Antineoplásicos/genética , MicroARNs/genética , Neoplasias de la Próstata/tratamiento farmacológico , Animales , Antimetabolitos Antineoplásicos/uso terapéutico , Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Proteínas Reguladoras de la Apoptosis/fisiología , Azacitidina/análogos & derivados , Azacitidina/uso terapéutico , Línea Celular Tumoral , Metilación de ADN , Metilasas de Modificación del ADN/antagonistas & inhibidores , Decitabina , Regulación hacia Abajo , Factor de Transcripción E2F6/genética , Factor de Transcripción E2F6/metabolismo , Factor de Transcripción E2F6/fisiología , Humanos , Masculino , Ratones , MicroARNs/metabolismo , Regiones Promotoras Genéticas , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/metabolismoRESUMEN
Over the years it has been important for humans to control the populations of harmful insects and insecticides have been used for this purpose in agricultural and horticultural sectors. Synthetic insecticides, owing to their various side effects, have been widely replaced by biological insecticides. In this review we attempt to describe three bacterial species that are known to produce insecticidal toxins of tremendous biotechnological, agricultural, and economic importance. Bacillus thuringiensis (BT) accounts for 90% of the bioinsecticide market and it produces insecticidal toxins referred to as delta endotoxins. The other two bacteria belong to the genera Photorhabdus and Xenorhabdus, which are symbiotically associated with entomopathogenic nematodes of the families Heterorhabditidae and Steinernematidae respectively. Whereas, Xenorhabdus and Photorhabdus exist in a mutualistic association with the entomopathogenic nematodes, BT act alone. BT formulations are widely used in the field against insects; however, over the years there has been a gradual development of insect resistance against BT toxins. No resistance against Xenorhabdus or Photorhabdus has been reported to date. More recently BT transgenic crops have been prepared; however, there are growing concerns about the safety of these genetically modified crops. Nematodal formulations are also used in the field to curb harmful insect populations. Resistance development to entomopathogenic nematodes is unlikely due to the physical macroscopic nature of infection. Xenorhabdus and Photorhabdus transgenes have not yet been prepared; but are predicted to be available in the near future. In this review we start with an overview of the synthetic insecticides and then discuss Bacillus thuringiensis, Xenorhabdus nematophilus, and Photorhabdus luminescens in greater detail.
Asunto(s)
Bacillus thuringiensis/crecimiento & desarrollo , Toxinas Bacterianas/metabolismo , Insectos , Control Biológico de Vectores , Photorhabdus/crecimiento & desarrollo , Xenorhabdus/crecimiento & desarrollo , Agricultura , Animales , Bacillus thuringiensis/metabolismo , Insectos/microbiología , Insectos/parasitología , Photorhabdus/metabolismo , Xenorhabdus/metabolismoRESUMEN
In the case of a soluble polymer supported synthesis, the tuning of the support solubility depending on the solvent offers new opportunities for combinatorial chemistry for two reasons. First, organic syntheses in solution are generally easily translated on a soluble polymer supported substrate. Second, complete automation of the three successive steps of combinatorial chemistry (synthesis, analytical control, biological test) is approached without releasing the synthesized compound from the support. We report in this paper the preliminary results toward automation of both soluble polymer supported syntheses and their subsequent monitoring by ESI mass spectrometry.
Asunto(s)
Técnicas Químicas Combinatorias/métodos , Compuestos Orgánicos/síntesis química , Polietilenglicoles/química , Automatización , Técnicas Químicas Combinatorias/instrumentación , Evaluación Preclínica de Medicamentos , Espectrometría de Masa por Ionización de ElectrosprayRESUMEN
The ptsH gene from Bacillus thuringiensis israelensis (Bti), coding for the phosphocarrier protein HPr of the phosphotransferase system has been cloned and overexpressed in Escherichia coli. Comparison of its primary sequence with other HPr sequences revealed that the conserved His15 and Ser46 residues were shifted by one amino acid and located at positions 14 and 45, respectively. The biological activity of the protein was not affected by this change. When expressed in a Bacillus subtilis ptsH deletion strain, Bti HPr was able to complement the functions of HPr in sugar uptake and glucose catabolite repression of the gnt and iol operons. A modified form of HPr was detected in Bti cells, and also when Bti ptsH was expressed in E. coli or B. subtilis. This modification was identified as phosphorylation, because alkaline phosphatase treatment converted the modified form to unmodified HPr. The phosphoryl bond in the new form of in vivo phosphorylated HPr was resistant to alkali treatment but sensitive to acid treatment, suggesting phosphorylation at a histidine residue. Replacement of His14 with alanine in Bti HPr prevented formation of the new form of phosphorylated HPr. The phosphorylated HPr was stable at 60 degrees C, in contrast with HPr phosphorylated at the N delta 1 position of His14 with phosphoenolpyruvate and enzyme I. (31)P-NMR spectroscopy was used to show that the new form of P-HPr carried the phosphoryl group bound to the N epsilon 2 position of His14 of Bti HPr. Phosphorylation of HPr at the novel site did not occur when Bti HPr was expressed in an enzyme I-deficient B. subtilis strain. In addition, P-(N epsilon 2)His-HPr did not transfer its phosphoryl group to the purified glucose-specific enzyme IIA domain of B. subtilis.
Asunto(s)
Bacillus thuringiensis/química , Bacillus thuringiensis/genética , Proteínas Bacterianas , Sistema de Fosfotransferasa de Azúcar del Fosfoenolpiruvato/química , Sistema de Fosfotransferasa de Azúcar del Fosfoenolpiruvato/genética , Fosfatasa Alcalina/metabolismo , Bacillus subtilis/metabolismo , Sitios de Unión , Clonación Molecular , Electroforesis en Gel de Poliacrilamida , Escherichia coli/metabolismo , Eliminación de Gen , Glucosa/metabolismo , Histidina/química , Calor , Concentración de Iones de Hidrógeno , Hidrólisis , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular , Mutagénesis , Sistema de Fosfotransferasa de Azúcar del Fosfoenolpiruvato/aislamiento & purificación , Fosforilación , Unión Proteica , Estructura Terciaria de Proteína , Proteínas Recombinantes/metabolismo , Temperatura , Factores de TiempoRESUMEN
OBJECTIVES: Over the past decade, the glial protein S-100beta has been used to detect cerebral injury in a number of clinical settings including cardiac surgery. Previous investigations suggest that S-100beta is capable of identifying patients with cerebral dysfunction after cardiopulmonary bypass. Whether detection of elevated levels S-100beta reflects long-term cognitive impairment remains to be shown. The present study evaluated whether perioperative release of S-100beta after coronary artery operations with cardiopulmonary bypass could predict early or late neuropsychologic impairment. METHODS: A total of 100 patients undergoing elective coronary bypass without a previous history of neurologic events were prospectively studied. To exclude noncerebral sources of S-100beta, we did not use cardiotomy suction or retransfusion of shed mediastinal blood. Serial perioperative measurements of S-100beta were performed with the use of a new sensitive immunoluminometric assay up to 8 hours after the operation. Patients underwent cognitive testing on a battery of 11 tests before the operation, before discharge from the hospital, and 3 months later. RESULTS: No significant correlation was found between S-100beta release and neuropsychologic measures either 5 days or 3 months after the operation. CONCLUSION: Despite using a sensitive immunoluminometric assay of S-100beta, we found no evidence to support the suggestion that early release of S-100beta may reflect long-term neurologic injury capable of producing cognitive impairment.
Asunto(s)
Puente Cardiopulmonar/efectos adversos , Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/etiología , Proteínas S100/sangre , Anestesia General , Ansiedad/diagnóstico , Ansiedad/etiología , Biomarcadores/sangre , Trastornos del Conocimiento/sangre , Trastorno Depresivo/diagnóstico , Trastorno Depresivo/etiología , Femenino , Humanos , Masculino , Trastornos de la Memoria/diagnóstico , Trastornos de la Memoria/etiología , Persona de Mediana Edad , Pruebas Neuropsicológicas , Estudios Prospectivos , Estadísticas no ParamétricasRESUMEN
The role of nutritional factors during CryIVA protoxin expression in Bacillus thuringiensis israelensis (Bti) has been investigated. Inorganic phosphate (Pi) was found to stimulate 135 kD protoxin synthesis by Bti cells. There was a corresponding increase in the cryIVA specific mRNA in the presence of Pi. Inorganic phosphate inhibited HPr kinase but activated HPr phosphatase, the two enzymes responsible for regulating the concentration of phosphorylated HPr in the cell. Addition of protein phosphatase inhibitors NaF and calyculin A during resuspension resulted in the inhibition of toxin synthesis by Bti cells. Calyculin A inhibited HPr phosphatase activity in the in vitro assay also. The concentration of phosphorylated HPr was upregulated when the cells were resuspended in the presence of calyculin A, while the levels of the same were lowered in the presence of Pi, as determined by Western blotting the respective cells. The efficiency of sporulation of Bti was not affected when Pi was added alone or along with the phosphatase inhibitor calyculin A.
Asunto(s)
Bacillus thuringiensis/efectos de los fármacos , Proteínas Bacterianas/biosíntesis , Toxinas Bacterianas/biosíntesis , Endotoxinas , Fosfatos/farmacología , Precursores de Proteínas/biosíntesis , Toxinas de Bacillus thuringiensis , Proteínas Bacterianas/genética , Toxinas Bacterianas/genética , Activación Enzimática , Regulación Bacteriana de la Expresión Génica , Proteínas Hemolisinas , Insecticidas/metabolismo , Toxinas Marinas , Oxazoles/farmacología , Fosfoproteínas Fosfatasas/antagonistas & inhibidores , Fosfoproteínas Fosfatasas/metabolismo , Precursores de Proteínas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Fluoruro de Sodio/farmacologíaRESUMEN
Bacillus thuringiensis subsp. israelensis (Bti) produces Cry IV A protoxin protein as part of the insecticidal crystal toxin during sporulation. This study was conducted with the objective of identifying environmental signals which regulate toxin synthesis by Bti. Glucose was found to repress Cry IV A toxin induction at the mRNA level. The repressive effect of glucose was dependent on a phosphorylation step since protein kinase inhibitor calphostin c relieved the 130-kD protoxin synthesis at both the mRNA and protein level. Phosphorylation of HPr, the phosphocarrier protein of the phosphotransferase system, occurred during glucose repression of Cry IV A toxin synthesis in Bti cells was seen by Western blotting with anti-phosphoserine antibody and rabbit anti-HPr serum. Phosphorylation of HPr in vivo as well as in the in vitro assay was inhibited by calphostin c, a specific inhibitor of serine/threonine kinase. Calphostin c had no effect on sporulation efficiency of Bti cells.
Asunto(s)
Bacillus thuringiensis/genética , Proteínas Bacterianas/genética , Toxinas Bacterianas/genética , Endotoxinas , Proteínas Serina-Treonina Quinasas , Animales , Anticuerpos , Bacillus thuringiensis/efectos de los fármacos , Bacillus thuringiensis/metabolismo , Toxinas de Bacillus thuringiensis , Proteínas Bacterianas/biosíntesis , Proteínas Bacterianas/metabolismo , Toxinas Bacterianas/biosíntesis , Inhibidores Enzimáticos/farmacología , Expresión Génica/efectos de los fármacos , Genes Bacterianos/efectos de los fármacos , Glucosa/farmacología , Proteínas Hemolisinas , Naftalenos/farmacología , Sistema de Fosfotransferasa de Azúcar del Fosfoenolpiruvato/metabolismo , Fosforilación , Proteína Quinasa C/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas , Proteínas Quinasas/inmunología , Proteínas Quinasas/metabolismo , ARN Bacteriano/genética , ARN Bacteriano/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Conejos , Esporas Bacterianas/efectos de los fármacosRESUMEN
Carney's syndrome consists of a combination of three rare tumours: gastric leiomyosarcoma, pulmonary chondroma and catecholamine-secreting paraganglioma. We describe a young woman with Carney's syndrome, who developed a lung abscess, due to obstruction of a bronchus by a chondroma, 11 yrs after having had a partial gastrectomy for a leiomyosarcoma.
Asunto(s)
Catecolaminas/metabolismo , Condroma/complicaciones , Leiomiosarcoma/complicaciones , Absceso Pulmonar/complicaciones , Neoplasias Pulmonares/complicaciones , Paraganglioma/complicaciones , Neoplasias Gástricas/complicaciones , Adulto , Femenino , Humanos , Paraganglioma/metabolismo , SíndromeRESUMEN
Tumor necrosis factor (TNF)-alpha is initially synthesized as an extracellular membrane-associated 26-kDa protein that is further cleaved at Ala76-Val77 to yield the soluble 17-kDa form. Recently, peptide-hydroxamate metalloproteinase inhibitors have been reported to block the proteolytic processing of TNF-alpha, thus suggesting that the putative TNF-alpha converting enzyme (TACE) is a zinc-dependent metalloendopeptidase. In this report, we characterize a TNF-alpha converting activity (TACA) that cleaves in vitro the human 26-kDa TNF-alpha at the physiological processing site. The chromatography steps followed for purification and the use of a panel of proteinase inhibitors indicate that the enzyme responsible for TACA is a membrane glycosylated metalloendopeptidase which is most likely different from the matrix-degrading metalloproteinases. The failure of TACA to process a Val77-->Gly77 precursor mutant emphasizes the importance of hydrophobic residue at P1' position. In addition, TACA is not able to cleave the mouse pro-TNF-alpha and does not catalyze in vitro the processing of other transmembrane proteins susceptible to metalloproteinase-mediated shedding, such as interleukin-6 or TNF receptors. These studies suggest the existence of an enzyme specific for TNF-alpha within the metalloproteinases involved in the processing/shedding of a number of cytokines and cytokine receptors.