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1.
EClinicalMedicine ; 24: 100417, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32775967

RESUMEN

BACKGROUND: There is limited evidence to inform treatment decision-making in adolescents experiencing first episode psychosis (FEP). In the MAPS trial (Managing Adolescent first Episode Psychosis: a feasibility Study), adolescents with FEP received either antipsychotic medication (AP), psychological intervention (PI), or both. We investigated treatment views of young people and family members across each treatment arm of MAPS. METHODS: Thirteen adolescents participating in MAPS and eighteen family members attended in-depth audio-recorded interviews to discuss trial treatments. Interviews were analysed using inductive Thematic Analysis, identifying salient themes across these accounts. FINDINGS: Family members in particular reported an urgent need for treatment regardless of type. Both AP and PI were broadly viewed as acceptable treatment approaches, but for differing reasons which participants weighed against a range of concerns. AP were often seen to reduce symptoms of psychosis, though participants expressed concerns about side effects. PI were viewed as interactive treatment approaches that helped improve understanding of psychosis and enhanced coping, although some found PI emotionally and cognitively challenging. Combining treatments was seen to maximise benefits, with a perceived interaction whereby AP facilitated engagement with PI. INTERPRETATION: Acceptability of and engagement with treatments for FEP may differ between individual young people and their family/carers. In order to be able to offer fully informed choices, and determine an optimum treatment approach for young people with FEP, definitive trial evidence should be established to determine wanted and unwanted treatment impacts. FUNDING: NIHR HTA programme (project number 15/31/04).

2.
J Clin Microbiol ; 30(1): 115-22, 1992 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1734042

RESUMEN

Tests for the detection of antibodies to Treponema pallidum are recommended for the confirmation of reactive nontreponemal test results and the accurate diagnosis of syphilis. The present-day use of Western blot (immunoblot) technology for the diagnosis of retroviruses prompted the development and evaluation of a Western blot assay with whole-cell T. pallidum as the antigen. The assay detected antibodies in syphilitic serum or plasma from dilutions of specimens incubated overnight with test strips. A test was considered positive when at least three of four major antigens having molecular masses of 15.5, 17, 44.5, and 47 kDa were detected. The Western blot assay had 93.8% sensitivity and 100% specificity for clinically defined samples. The Western blot assay was compared with double-staining fluorescent treponemal antibody absorption [FTA-ABS (DS)], which had a sensitivity and a specificity of 91.7 and 92.0%, respectively. Dilution series studies of syphilis-positive specimens indicated that the Western blot assay has an endpoint of reactivity at least 3 to 4 serial dilutions greater than that for FTA-ABS (DS). Overall, the greater than 95% agreement between the Western blot assay and FTA-ABS (DS) for clinically defined specimens indicates that the sensitivity of the Western blot assay is equal to or greater than that of FTA-ABS (DS). The Western blot assay demonstrated no false-positive or equivocal reactivities for nonsyphilitic specimens, including normal specimens (both plasma and serum), biological false-positives, and specimens with elevated gamma globulin or antinuclear antibody. We conclude that the high sensitivity and specificity of the T. pallidum Western blot assay, together with its simplicity and objectivity, make it a good confirmatory test for syphilis.


Asunto(s)
Western Blotting , Sífilis/diagnóstico , Treponema pallidum/aislamiento & purificación , Animales , Anticuerpos Antinucleares/sangre , Anticuerpos Antibacterianos/sangre , Antígenos Bacterianos/análisis , Prueba de Absorción de Anticuerpos Fluorescentes de Treponema , Humanos , Masculino , Conejos , Factor Reumatoide/sangre , Sensibilidad y Especificidad , Abuso de Sustancias por Vía Intravenosa/sangre , Serodiagnóstico de la Sífilis , Treponema pallidum/inmunología
3.
J Lipid Res ; 30(1): 109-20, 1989 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2465366

RESUMEN

Human plasma low density lipoproteins (LDL) isolated by ultracentrifugation showed a single band corresponding to apolipoprotein B-100 (apoB-100) by SDS-gradient gel electrophoresis (GGE). In turn, apoB-100 of LDL precipitated from plasma by dextran sulfate-500 (DS)-MgCl2 exhibited several bands indicative of a degradative process. The degradation was more extensive at 0 degrees C than at either 23 degrees C or 37 degrees C, and appeared to be related to a protease activity that cleaved both the synthetic peptide, Z-Phe-Arg-7-amido-4-methylcoumarin (Z-Phe-Arg-AMC) and apoB-100. Proteolysis was proportional to the DS added to the plasma, was prevented by the kallikrein inhibitor, D-Phe-L-Phe-L-Arg-CHCl2, and was significantly decreased in plasma specimens of patients with either factor XII or prekalikrein deficiency. LDL pre-purified by ultracentrifugation and then precipitated by DS in the absence of plasma exhibited no proteolysis. However, proteolysis was observed when LDL interacted with kallikrein. The two main apolipoproteins of HDL3, apoA-I and apoA-II, were not affected by this proteolytic process. We interpret the results to indicate that the negatively charged surface provided by DS accelerates in plasma the autoactivation of factor XII and the activation of prekallikrein, resulting in an increase of the effective concentration of kallikrein and possibly other proteases and proteolysis of LDL-apoB-100. The higher degree of the DS-induced proteolysis of apoB-100 at 0 degrees C than at 23 degrees C is likely the consequence of enhanced autoactivation of factor XII and a decreased efficiency of plasma inhibitors, such as C1-inhibitor. We speculate that the proteolysis of apoB-100 induced by DS is not limited to this polyanion, but may also be the property of other negatively charged agents, particularly at cold temperatures.


Asunto(s)
Apolipoproteínas B/sangre , Lipoproteínas LDL/sangre , Apolipoproteína B-100 , Sulfato de Dextran , Dextranos , Factor XII/análisis , Humanos , Magnesio , Cloruro de Magnesio , Precalicreína/análisis , Serina Endopeptidasas/metabolismo , Temperatura , Ultracentrifugación
4.
J Lipid Res ; 29(6): 797-808, 1988 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3171397

RESUMEN

In previous studies we reported that polymorphonuclear cell (PMN) elastase cleaves apoB-100 of human plasma low density lipoprotein (LDL) into seven or eight large Mr fragments (1, Polacek, D., R.E. Byrne, G.M. Fless, and A.M. Scanu. 1986. J. Biol. Chem. 261: 2057-2063). In the present studies we examined the interaction of native and elastase-digested LDL (ED-LDL) with primary cultures of human monocyte-derived macrophages (HMD-M). For this purpose LDL was digested with purified PMN elastase, re-isolated by ultracentrifugation at d 1.063 g/ml to remove the enzyme, and radiolabeled with 125I. At all LDL concentrations in the medium, the degradation of 125I-labeled ED-LDL was 1.5- to 2.5-fold greater than that of 125I-labeled native LDL, and for both lipoproteins species it was further enhanced by prior incubation of the cells in autologous lipoprotein-deficient serum (ALPDS). ED-LDL incubated with HMD-M in a medium containing [14C]oleate stimulated cholesteryl [14C]oleate formation 2- to 3-fold more than native LDL. In competitive degradation experiments, unlabeled ED-LDL did not inhibit the degradation of 125I-labeled acetylated LDL, whereas it caused a 90% inhibition of the degradation of 125I-labeled native LDL. At 4 degrees C, the binding of both 125I-labeled native and 125I-labeled ED-LDL was specific and of a high affinity. At saturation (Bmax), the binding of 125I-labeled ED-LDL was 2-fold higher (68 ng/mg cell protein) than that of 125I-labeled native LDL (31 ng/mg), with Kd values of 6.5 x 10(-8) M and 2.1 x 10(-8) M, respectively. A possible explanation of the binding data was provided by electrophoretic analyses suggesting that ED-LDL was twice the size of native LDL and thus potentially capable of delivering proportionately more cholesterol to the cells. Taken together, the results indicate that 1) digestion of LDL by purified PMN elastase results in a greater mass of ED-LDL (relative to native LDL) being degraded per unit time by HMD-M; 2) uptake of ED-LDL occurs via the LDL receptor; and 3) LDL digested by PMN elastase undergoes a physical change that may be responsible for its unique interactions with HMD-M. We speculate that if this process were to occur in vivo during an inflammatory process, macrophages could acquire excess cholesterol and be transformed into foam cells which are considered to be precursors of the atherosclerotic process.


Asunto(s)
Leucocitos Mononucleares/metabolismo , Lipoproteínas LDL/metabolismo , Macrófagos/metabolismo , Neutrófilos/enzimología , Elastasa Pancreática/sangre , Receptores de LDL/metabolismo , Animales , Ésteres del Colesterol/metabolismo , Humanos , Ratones , Neutrófilos/metabolismo , Oxidación-Reducción
5.
J Biol Chem ; 261(5): 2057-63, 1986 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-3632977

RESUMEN

In vitro incubation of human plasma low density lipoproteins (LDL) with human blood polymorphonuclear cells (PMN) for 1 h at 37 degrees C resulted in an increased (2-4-fold) release into the medium of an enzymatic activity which co-eluted with LDL by column chromatography at physiological ionic strength but dissociated from it in high salt media in an ultracentrifugal field. The release of this enzymatic activity increased with increasing concentration of LDL in the medium and caused the hydrolysis of the LDL apoprotein B100 as indicated by the appearance of 7-8 low molecular weight bands (immunoreactive with anti-LDL) which were not present in the electropherogram of control LDL. The proteolytic activity was identified as an elastase by the following criteria: 1) capacity to hydrolyze the synthetic substrate methoxysuccinyl-Ala-Ala-Pro-Val-4-methylcoumaryl-7-amide known to be specific for the PMN elastase, 2) pattern of apo-B proteolysis identical to that exhibited by pure PMN elastase, 3) inhibition of the proteolysis by the elastase inhibitor methoxysuccinyl-Ala-Ala-Pro-Val-CH2Cl, 4) identity in molecular weight (28,000-30,000) of this activity with a pure preparation of PMN elastase labeled with [3H]diisopropylfluorophosphate. Based on thiobarbituric acid analyses and the lack of effect by vitamin E, oxidative events appeared to play no detectable role in apo-B proteolysis. Since we previously reported (Byrne, R. E., Polacek, D., Gordon, J. I., and Scanu, A. M. (1984) J. Biol. Chem. 259, 14531-14543) that high density lipoprotein-3 promotes the in vitro release of PMN elastase which cleaves apo-A-II, it is apparent that in vitro, both LDL and high density lipoprotein, two of the major plasma lipoprotein classes, can affect the export from PMN of an elastase which exhibits proteolytic action on apo-B and apo-A-II.


Asunto(s)
Apolipoproteínas B/metabolismo , Lipoproteínas LDL/metabolismo , Neutrófilos/enzimología , Elastasa Pancreática/metabolismo , Clorometilcetonas de Aminoácidos/farmacología , Apolipoproteína B-100 , Electroforesis en Gel de Poliacrilamida , Humanos , Lipoproteínas HDL/metabolismo , Neutrófilos/metabolismo , Oligopéptidos/metabolismo , Oxidación-Reducción , Elastasa Pancreática/antagonistas & inhibidores , Fragmentos de Péptidos/metabolismo
6.
CRC Crit Rev Biochem ; 20(1): 37-71, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3514123

RESUMEN

The steps involved in the initial assembly of apolipoproteins and lipids into supramolecular arrays (nascent lipoprotein particles) are largely unknown. Examination of the proteolytic processing and compartmentalization of the primary translation products of apolipoprotein mRNAs represents one approach to deciphering the molecular details of lipoprotein assembly. The structures of the primary translation products of seven mammalian apolipoprotein mRNAs has been determined in the past several years. The organization of apolipoprotein signal peptides is typical of eukaryotic prepeptides, although an unusual degree of sequence conservation is present among the signal segments of apo AI, AIV, and E. For those apolipoprotein sequences studied in detail, SRP-dependent cotranslational translocation and proteolytic processing appears to be highly efficient and results in sequestration of the processed protein within the lumen of the endoplasmic reticulum (ER). However the mechanism by which these lipid-binding proteins avoid arrest during their translocation through the lipid bilayer of the ER membrane remains obscure. The two principal human HDL apolipoproteins undergo novel extracellular post-translational proteolytic processing, which results in removal of nonhomologous propeptides. The proteases responsible for proapo AI and AII processing appear to be different. The processing of these proapolipoproteins provides a potential series of steps for regulating the ordered assembly of HDL constituents.


Asunto(s)
Apolipoproteínas/metabolismo , Lipoproteínas/metabolismo , Animales , Apolipoproteínas/genética , Transporte Biológico , Compartimento Celular , Retículo Endoplásmico/metabolismo , Aparato de Golgi/metabolismo , Humanos , Membranas Intracelulares/metabolismo , Metabolismo de los Lípidos , Sustancias Macromoleculares , Péptido Hidrolasas/metabolismo , Biosíntesis de Proteínas , Procesamiento Proteico-Postraduccional , Señales de Clasificación de Proteína/metabolismo , ARN Mensajero/metabolismo , Relación Estructura-Actividad
7.
Cancer ; 56(3): 652-4, 1985 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-2988751

RESUMEN

The charts of 112 patients with small cell lung cancer were reviewed in a retrospective fashion in order to define the role of the radionuclide bone scan and bone marrow biopsy in the staging of this disease. Both a radionuclide bone scan and bone marrow biopsy were performed on all patients at the time of diagnosis. Sixty-one percent of patients had a negative bone scan and negative biopsy; 22% had a positive bone scan and negative biopsy; 8% had a negative scan and positive biopsy; and 9% had a positive scan and positive biopsy. In 21 of the 44 patients with osseous involvement, no other focus of distant metastasis was found. The bone scan showed greater than or equal to 3 areas of increased uptake in 15 patients, 2 areas of increased uptake in 13 patients, and 1 area in 7 patients. The number of patients with bone marrow biopsy results positive for tumor in these 3 groups were 5, 3, and 2, respectively. Our study shows a lack of correlation between bone scan and bone marrow biopsy results. The bone scan and bone marrow biopsy identify independent patterns of osseous metastasis. Both procedures should be performed in the evaluation of patients with small cell lung cancer.


Asunto(s)
Médula Ósea/patología , Carcinoma de Células Pequeñas/patología , Neoplasias Pulmonares/patología , Pulmón/patología , Biopsia , Neoplasias Óseas/diagnóstico por imagen , Neoplasias Óseas/patología , Neoplasias Óseas/secundario , Huesos/diagnóstico por imagen , Carcinoma de Células Pequeñas/diagnóstico por imagen , Carcinoma de Células Pequeñas/secundario , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Estadificación de Neoplasias , Pronóstico , Cintigrafía
8.
J Lipid Res ; 26(3): 351-9, 1985 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3921637

RESUMEN

The nonionic detergent Triton WR-1339 was injected intravenously into normolipidemic dogs in a single dose of 150 mg/kg body weight followed by three other injections (75 mg/kg) on days 2, 6, and 12. The Triton produced a significant elevation of the plasma cholesterol of these animals, but not of their triglyceride levels, and profound changes of their plasma lipoproteins, particularly of the high density lipoprotein class. These changes were dependent on the concentration of Triton attained in plasma; when the levels were above 1.5 mg/ml, density gradient ultracentrifugation, electrophoretic, and chemical analyses indicated that an interaction between Triton and HDL had occurred. This interaction was attended by a gradual loss of the surface components of HDL, namely apoA-I, phospholipids, and unesterified cholesterol, and by the appearance of two cholesteryl ester-rich lipoproteins of d 1.019-1.024 g/ml and d 1.038-1.058 g/ml containing apoA-I and proteins with electrophoretic mobilities of apoB, apoE, and apoA-IV. At the time that these changes had occurred, the activities of the enzymes lecithin: cholesterol acyltransferase and post-heparin lipase were unaffected. When 125I-labeled apoA-I was injected intravenously into animals receiving Triton, the residence time of the radiolabeled protein in plasma increased from a control value of 3.1 days to 7.2 days. However, the apparent half-times of the radiolabeled apoA-I varied among the lipoprotein fractions it was associated with: d 1.119-1.159 g/ml, 5.28 days; d 1.019-1.024 g/ml, 7.55 days, and d 1.038-1.058 g/ml, 5.39 days.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Lipoproteínas HDL/sangre , Lipoproteínas/sangre , Polietilenglicoles/farmacología , Animales , Apolipoproteína A-I , Apolipoproteínas A/sangre , Centrifugación por Gradiente de Densidad , Colesterol/sangre , Perros , Electroforesis/métodos , Inmunoensayo/métodos , Inyecciones Intravenosas , Cinética , Masculino , Polietilenglicoles/administración & dosificación , Triglicéridos/sangre
9.
J Biol Chem ; 259(23): 14531-6, 1984 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-6094562

RESUMEN

Human high-density lipoprotein class-3 (HDL3) was incubated with freshly isolated blood polymorphonuclear leukocytes (PMN) at 37 and 4 degrees C. At both temperatures the release of proteolytic activity (PA) causing the specific hydrolysis of apo-A-II was dependent on the concentration of HDL3 in the medium. At 37 degrees C, the efflux of PA was linear and no saturation was reached up to an HDL3 protein concentration in the medium of 800 micrograms/ml. In turn, at 4 degrees C, maximal PA release was reached at a concentration below 600 micrograms/ml of HDL3 protein/ml in the medium. Canine HDL, which contains apo-A-I, but not apo-A-II, was as effective as human HDL3 in promoting the release of PA from PMN. This property was also exhibited by egg lecithin/cholesterol vesicles containing apo-A-I. At 4 degrees C, there was no strict correlation between efflux of PA affected by HDL3 and specific binding of 125I-apo-A-I (HDL3). In competitive binding experiments, a 50-fold excess of unlabeled HDL3 prevented more than 90% of the binding of 125I-apo-A-I (HDL3) to PMN, whereas an excess of unlabeled low-density lipoprotein exhibited no effect. When human HDL3 was incubated with PMN at 4 or 37 degrees C and then subjected to ultracentrifugation at d 1.21 g/ml, most of the PA that was initially associated with this lipoprotein was recovered in the bottom of the tube. By gel filtration, both PA and HDL3 were in the same peak in a low ionic strength buffer, but were dissociated from each other by a high-salt solution (d 1.21 g/ml). We conclude that both naturally occurring HDLs and apo-A-I-stabilized lipid vesicles favor the release from PMN of an enzymatic activity which cleaves human apo-A-II. This release appears to be dependent both on the interaction of the cells with the lipoprotein ligand and on the lipoprotein surface area acting as the acceptor for the enzyme, probably through electrostatic forces.


Asunto(s)
Apolipoproteínas A/sangre , Proteínas Portadoras , Lipoproteínas HDL/sangre , Neutrófilos/enzimología , Elastasa Pancreática/sangre , Péptido Hidrolasas/sangre , Proteínas de Unión al ARN , Receptores de Lipoproteína , Animales , Apolipoproteína A-I , Apolipoproteína A-II , Perros , Humanos , Radioisótopos de Yodo , Cinética , Lipoproteínas HDL3 , Receptores de Superficie Celular/metabolismo , Temperatura
11.
J Biol Chem ; 259(23): 14537-43, 1984 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-6438100

RESUMEN

The proteolytic activity directed against apolipoprotein A-II (apo-A-II) which is released from human blood polymorphonuclear cells (PMN) when they are incubated with human plasma high-density lipoprotein-3 (HDL3) was studied to assess the properties and site specificity of the enzyme. When 125I-apo-A-II-labeled HDL3 was incubated with the PMN protease at 37 degrees C, a complete cleavage of apo-A-II was observed which paralleled the formation of bands of approximately 11,000 and 7,000 daltons by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The 7,000-dalton component had the following N-terminal sequence: NH2-Thr-Asp-Tyr-Gly-Lys-Asp-Leu-Met-Glu-Lys. This corresponds to residues 19 through 28 of the intact apo-A-II monomer. Methoxysuccinyl (MeO-Suc)-Ala-Ala-Pro-Val-chloromethylketone-(CH2Cl) caused a 90% inhibition of apo-A-II hydrolysis at the highest concentration tested (6 X 10(-4)M). Besides apo-A-II, the PMN enzyme also hydrolyzed a synthetic substrate, MeO-Suc-Ala-Ala-Pro-Val-4-nitroanilide and its 4-methylcoumaryl-7-amide analogue. The protease appeared to have a mass of 28,000 daltons as assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the [3H]diisopropylfluorophosphate-labeled PMN enzyme. That the PMN enzyme which cleaves apo-A-II is an elastase was derived from the following criteria: 1) cleavage at the Val-X bond in apo-A-II and in the two synthetic substrates studied; 2) prevention of the cleavage by MeO-Suc-Ala-Ala-Pro-Val-CH2Cl, a known specific elastase inhibitor; and 3) a mass comparable to that reported for a pure PMN elastase. These studies establish that apolipoproteins can be suitable substrates for enzymes of the elastase family.


Asunto(s)
Apolipoproteínas A/sangre , Lipoproteínas HDL/sangre , Neutrófilos/enzimología , Elastasa Pancreática/sangre , Apolipoproteína A-II , Electroforesis en Gel de Poliacrilamida , Humanos , Isoflurofato/farmacología , Lipoproteínas HDL3 , Peso Molecular , Tritio
12.
Cancer Treat Rep ; 68(11): 1375-7, 1984 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-6094002

RESUMEN

Fifty-five patients with small cell lung cancer underwent computerized cranial tomography (CCT) and a complete neurologic examination as part of their staging work-up. Fifteen patients (27%) had evidence of brain metastases detected by CCT at the time of diagnosis. Eleven of these 15 patients had new focal abnormalities upon neurologic examination. Of the 44 patients who had no new focal abnormalities upon neurologic examination, four (9%) had CCT findings consistent with brain metastases, and, in three of these patients, the central nervous system was the only site of metastatic disease. Thus, through the use of CCT as a routine procedure in the staging of small cell lung cancer, three patients whose tumors would otherwise have been classified as limited-stage were found to have extensive-stage disease.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Carcinoma de Células Pequeñas/diagnóstico por imagen , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Encefálicas/secundario , Humanos , Metástasis de la Neoplasia , Tomografía Computarizada por Rayos X
13.
Am J Clin Oncol ; 6(3): 301-4, 1983 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6846248

RESUMEN

Sixteen patients with advanced squamous cell carcinoma of the head and neck were treated with a 48-hour I.V. vindesine infusion. The dosage was 3 mg/m2/48 hours every 2 weeks. Toxicity consisted of leukopenia, paresthesias, and phlebitis. Major objective responses were seen in four patients (one CR, three PR), with a median duration of 4 months.


Asunto(s)
Antineoplásicos/administración & dosificación , Carcinoma de Células Escamosas/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Vinblastina/análogos & derivados , Anciano , Antineoplásicos/uso terapéutico , Evaluación de Medicamentos , Femenino , Humanos , Infusiones Parenterales , Masculino , Persona de Mediana Edad , Vinblastina/administración & dosificación , Vinblastina/uso terapéutico , Vindesina
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