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Itaconate was initially identified as an antimicrobial compound produced by myeloid cells. Beyond its antimicrobial role, itaconate may also serve as a crucial metabolic and immune modulator. We therefore examined the roles of aconitate decarboxylase 1 (Acod1) and itaconate in house dust mite (HDM)-sensitized and -challenged mice, a model of T helper 2 (Th2)-driven allergic airways disease. HDM treatment induced lung Acod1 mRNA expression and bronchoalveolar lavage (BAL) itaconate levels in wild-type C57BL/6 mice. Acod1 knockout mice (Acod1-KO) with negligible BAL itaconate showed heightened HDM-induced type 2 cytokine expression, increased serum IgE, and enhanced recruitment of Th2 cells in the lung, indicating a shift towards a more pronounced Th2 immune response. Acod1-KO mice also showed increased eosinophilic airway inflammation and hyperresponsiveness. Experiments in chimeric mice demonstrated that bone marrow from Acod1-KO mice is sufficient to increase type 2 cytokine expression in wild-type mice, and that restitution of bone marrow from wild type mice attenuates mRNA expression of Th2 cytokines in Acod1-KO mice. Specific deletion of Acod1 in lysozyme-secreting macrophages (LysM-cre+Acod1flox/flox) recapitulated the exaggerated phenotype observed in whole-body Acod1-KO mice. Adoptive transfer of Acod1-KO bone marrow-derived macrophages also increased lung mRNA expression of Th2 cytokines. In addition, treatment of Th2-polarized CD4 cells with itaconate impeded Th2 cell differentiation, as shown by reduced expression of Gata3 and decreased release of IL-5 and IL-13. Finally, public datasets of human samples show lower Acod1 expression in subjects with allergic asthma, consistent with a protective role of itaconate in asthma pathogenesis. Together, these data suggest that itaconate plays a protective, immunomodulatory role in limiting airway type 2 inflammation after allergen challenge by attenuating T cell responses.
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Sex differences in immune responses impact cancer outcomes and treatment response, including in glioblastoma (GBM). However, host factors underlying sex specific immune-cancer interactions are poorly understood. Here, we identify the neurotransmitter γ-aminobutyric acid (GABA) as a driver of GBM-promoting immune response in females. We demonstrated that GABA receptor B (GABBR) signaling enhances L-Arginine metabolism and nitric oxide synthase 2 (NOS2) expression in female granulocytic myeloid-derived suppressor cells (gMDSCs). GABBR agonist and GABA analog promoted GBM growth in females in an immune-dependent manner, while GABBR inhibition reduces gMDSC NOS2 production and extends survival only in females. Furthermore, female GBM patients have enriched GABA transcriptional signatures compared to males, and the use of GABA analogs in GBM patients is associated with worse short-term outcomes only in females. Collectively, these results highlight that GABA modulates anti-tumor immune response in a sex-specific manner, supporting future assessment of GABA pathway inhibitors as part of immunotherapy approaches.
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In most mammals the pancreas develops from the foregut endoderm as ventral and dorsal buds. These buds fuse and develop into a complex organ composed of endocrine, exocrine and ductal components. This developmental process depends upon an integrated network of transcription factors. Gene targeting experiments have revealed critical roles for Pdx1, Isl1, Pax4, Pax6 and Nkx2-2 (refs 3,4,5,6,7, 8,9,10). The homeobox gene HLXB9 (encoding HB9) is prominently expressed in adult human pancreas, although its role in pancreas development and function is unknown. To facilitate its study, we isolated the mouse HLXB9 orthologue, Hlxb9. During mouse development, the dorsal and ventral pancreatic buds and mature beta-cells in the islets of Langerhans express Hlxb9. In mice homologous for a null mutation of Hlxb9, the dorsal lobe of the pancreas fails to develop. The remnant Hlxb9-/- pancreas has small islets of Langerhans with reduced numbers of insulin-producing beta-cells. Hlxb9-/- beta-cells express low levels of the glucose transporter Glut2 and homeodomain factor Nkx 6-1. Thus, Hlxb9 is key to normal pancreas development and function.
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Proteínas de Homeodominio/genética , Islotes Pancreáticos/anomalías , Proteínas del Tejido Nervioso , Páncreas/anomalías , Factores de Transcripción/genética , Animales , Proteínas de Unión al ADN/metabolismo , Proteínas del Ojo , Factores de Transcripción Forkhead , Genotipo , Glucagón/metabolismo , Proteína Homeobox Nkx-2.2 , Proteínas de Homeodominio/metabolismo , Humanos , Inmunohistoquímica , Insulina/metabolismo , Islotes Pancreáticos/embriología , Islotes Pancreáticos/metabolismo , Proteínas con Homeodominio LIM , Ratones , Modelos Genéticos , Datos de Secuencia Molecular , Neuronas Motoras/metabolismo , Proteínas Nucleares , Factor de Transcripción PAX6 , Factores de Transcripción Paired Box , Páncreas/embriología , Páncreas/metabolismo , Polipéptido Pancreático/metabolismo , Proteínas Represoras , Somatostatina/metabolismo , Factores de Tiempo , Transactivadores/metabolismo , Factores de Transcripción/metabolismo , Proteínas de Pez CebraRESUMEN
PURPOSE: To evaluate the predictive value of computed tomography (CT) scanning and single-photon emission computed tomography (SPECT) gallium (Ga) scanning in the disease-free survival of patients receiving high-dose chemotherapy and autologous stem-cell transplantation for non-Hodgkin's lymphoma (NHL). PATIENTS AND METHODS: One hundred forty-three patients undergoing transplant for NHL underwent CT scanning of chest, abdomen, and pelvis, and a SPECT Ga scan before transplantation and at day + 100 after transplant. The failure-free survival (FFS) by scan result was analyzed. RESULTS: In the diffuse aggressive lymphoma patients, the 1-year FFS for patients having a positive SPECT Ga scan at day + 100 was 15% compared with a 3-year FFS of 47% for those with a negative scan (P < .001). Patients with a positive CT scan at day + 100 had a 36% 3-year FFS, and those with a negative CT scan had a 39% 3-year FFS (P = not significant [NS]). An analysis of the combination of CT scan and SPECT Ga scan results at day + 100 posttransplant demonstrated a 3-year FFS of 14% if they were both abnormal; if the CT was positive and Ga was negative, the 3-year FFS was 68%; positive Ga with a negative CT was 25%; and both negative was 34% (P = .0015). For the patients with follicular NHL, those with a positive SPECT Ga at day + 100 had a 14% 1-year FFS compared with those with a negative scan, who had a 45% 3-year FFS (P < .001). In the follicular NHL patients, the 3-year FFS of those with a positive CT was 17% compared with a 64% 3-year FFS for patients with a negative CT scan (P < .001). CONCLUSION: The use of SPECT Ga scan at day + 100 posttransplant for evaluation of disease activity in patients with diffuse aggressive NHL was highly predictive of eventual outcome and was more predictive than the CT scan results. However, for patients with follicular NHL, the addition of SPECT Ga scanning to CT scanning did not add substantially to the evaluation of transplant outcome.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Radioisótopos de Galio , Trasplante de Células Madre Hematopoyéticas , Linfoma no Hodgkin/terapia , Tomografía Computarizada de Emisión de Fotón Único , Tomografía Computarizada por Rayos X , Adolescente , Adulto , Terapia Combinada , Supervivencia sin Enfermedad , Femenino , Humanos , Linfoma Folicular/diagnóstico por imagen , Linfoma Folicular/mortalidad , Linfoma Folicular/terapia , Linfoma no Hodgkin/diagnóstico por imagen , Linfoma no Hodgkin/mortalidad , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Trasplante AutólogoRESUMEN
PURPOSE: To evaluate the effectiveness and safety of samarium-153 (153Sm) lexidronam (EDTMP) in a double-blind, placebo-controlled study. PATIENTS AND METHODS: Patients with painful bone metastases secondary to a variety of primary malignancies were randomized to receive 153Sm-EDTMP 0.5 or 1.0 mCi/kg, or placebo. Treatment was unblinded for patients who did not respond by week 4, with those who had received placebo eligible to receive 1.0 mCi/kg of active drug in an open-label manner. Patient and physician evaluations were used to assess pain relief, as was concurrent change in opioid analgesia. RESULTS: One hundred eighteen patients were enrolled onto the study. Patients who received 1.0 mCi/kg of active drug had significant reductions in pain during each of the first 4 weeks in both patient-rated and physician-rated evaluations. Pain relief was observed in 62% to 72% of those who received the 1.O-mCi/kg dose during the first 4 weeks, with marked or complete relief noted in 31% by week 4. Persistence of pain relief was seen through week 16 in 43% of patients who received 1.0 mCi/kg, of active drug. A significant correlation (P = .01) was observed between reductions in opioid analgesic use and pain scores only for those patients who received 1.0 mCi/kg 153Sm-EDTMP. Bone marrow suppression was mild, reversible, and not associated with grade 4 toxicity. CONCLUSION: A single dose of 1.0 mCi/kg of 153Sm-EDTMP provided relief from pain associated with bone metastases. Pain relief was observed within 1 week of administration and persisted until at least week 16 in the majority of patients who responded.
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Analgésicos no Narcóticos/uso terapéutico , Neoplasias Óseas/secundario , Compuestos Organometálicos/uso terapéutico , Compuestos Organofosforados/uso terapéutico , Dolor Intratable/tratamiento farmacológico , Cuidados Paliativos , Adulto , Anciano , Anciano de 80 o más Años , Analgésicos no Narcóticos/administración & dosificación , Analgésicos no Narcóticos/efectos adversos , Neoplasias Óseas/complicaciones , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Compuestos Organometálicos/administración & dosificación , Compuestos Organometálicos/efectos adversos , Compuestos Organofosforados/administración & dosificación , Compuestos Organofosforados/efectos adversos , Dimensión del Dolor , Dolor Intratable/etiologíaRESUMEN
Platelet-activating factor (PAF) is a potent inflammatory mediator that is thought to play a role in cutaneous inflammation. These studies used mass spectrometry to examine the molecular species of PAF precursor glycerophosphocholine lipids (GPC) as well as the biosynthesis of PAF and other sn-2 acetyl-GPC in a human keratinocyte-derived cell line (HaCaT keratinocytes). Approximately 28% of HaCaT keratinocyte GPC consisted of 1-alkyl species, and the relative amounts of the sn-1 alkyl constituents of the PAF precursor 1-alkyl-2-acyl-GPC were as follows: hexadecyl > octadecenyl > octadecyl. Ionophore (A23187)-stimulated HaCaT keratinocytes synthesized both PAF (1-hexadecyl, 1-octadecenyl, and 1-octadecyl species) and less potent 1-acyl analogs (1-palmitoyl, 1-oleoyl, and 1-stearoyl species). PAF production was rapid and maximal by 10 min. The major species of sn-2acetyl-GPC at 2.5 min were 1-hexadecyl-2-acetyl-GPC (2.2 ng/10(6) cells) and 1-palmitoyl-2-acetyl-GPC (2.4 ng/10(6) cells). HaCaT keratinocytes also synthesized PAF and 1-acyl PAF analogs when stimulated with the peptide growth factor endothelin-1 and the nonhydrolyzable PAF receptor agonist carbamyl-PAF. Both 1-hexadecyl-2- acetyl-GPC and 1-palmitoyl-2-acetyl-GPC stimulated intracellular calcium mobilization in HaCaT cells, indicating that these sn-2 acetyl-GPC act in autocrine fashion. These studies revealed that the human keratinocyte-derived cell line HaCaT can synthesize significant amounts of PAF and 1-acyl analogs in vitro from both nonspecific (A23187) and specific (endothelin-1, carbamyl-PAF) stimulation, suggesting a role for this inflammatory lipid mediator in keratinocyte pathophysiology.
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Queratinocitos/metabolismo , Factor de Activación Plaquetaria/biosíntesis , Calcimicina/farmacología , Calcio/metabolismo , Línea Celular , Endotelina-1/farmacología , Humanos , Membranas Intracelulares/metabolismo , Factor de Activación Plaquetaria/análogos & derivados , Factor de Activación Plaquetaria/farmacología , Estimulación QuímicaRESUMEN
Oxidation of phospholipids results in chain-shortened fragments and oxygenated derivatives of polyunsaturated sn-2 fatty acyl residues, generating a myriad of phospholipid products. Certain oxidation products of phosphatidylcholine bind to and activate the human receptor for PAF, and these PAF-like lipids are potent, selective inflammatory mediators. Formation of PAF-like lipids is nonenzymatic and so their accumulation is unregulated. PAF-like lipids are produced in vivo in response to oxidative stresses and are responsible for attendant acute inflammatory responses. PAF-like lipids almost exclusively contain an ether-linked alkyl residue at the sn-1 position of the phosphatidylcholine backbone and molecular identification of these is facilitated by phospholipase A(1) treatment to remove the bulk of the inactive phospholipids. The identity of biologically active species generated by oxidative fragmentation and oxidation can be elucidated by understanding relevant reactions leading to the formation of PAF-like lipids, and then their structure can be established by tandem mass spectrometry and chemical synthesis.
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Peroxidación de Lípido/fisiología , Fosfolípidos/química , Fosfolípidos/metabolismo , Receptores de Superficie Celular , Receptores Acoplados a Proteínas G , Animales , Cricetinae , Radicales Libres/metabolismo , Cromatografía de Gases y Espectrometría de Masas , Glicerofosfolípidos/química , Glicerofosfolípidos/metabolismo , Humanos , Inflamación/inducido químicamente , Inflamación/metabolismo , Lipoproteínas LDL/metabolismo , Espectrometría de Masas , Oxidación-Reducción , Fosfatidilcolinas/química , Factor de Activación Plaquetaria/metabolismo , Glicoproteínas de Membrana Plaquetaria/metabolismo , Humo/efectos adversosRESUMEN
Leukocytes labeled with 99mTc-HMPAO and 111In have been used extensively in imaging inflammatory disorders, including inflammatory bowel disease (IBD), which has the appearance of tubular bowel activity. Peritonitis is inflammation of the serosal surfaces lining the peritoneal cavity which envelopes the bowel, giving a pattern of diffuse abdominal uptake on imaging. We present a case of an elderly man with surgically and pathologically confirmed peritonitis whose preoperative leukocyte scan mimicked the findings of IBD. Our findings suggest that diffuse peritonitis can mimic IBD on an 111In-leukocyte scan.
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Radioisótopos de Indio , Enfermedades Inflamatorias del Intestino/diagnóstico por imagen , Leucocitos , Peritonitis/diagnóstico por imagen , Abdomen/diagnóstico por imagen , Anciano , Diagnóstico Diferencial , Humanos , Masculino , CintigrafíaRESUMEN
UNLABELLED: The objective of this work was to determine the potential clinical usefulness of SPECT to image 511-keV annihilation photons. METHODS: A triple-headed gamma camera equipped with ultra-high-energy collimators was used to image 18F. Sensitivity measurements were carried out and the FWHM and FWTM were determined in air and for a unit-density scattering medium. Additionally, tomographic phantom studies were acquired to evaluate image quality. RESULTS: The sensitivities of the three cameras were, for all practical purposes, identical. At a source-to-collimator distance of 100 mm, the FWHM and FWTM were 13 and 29 mm, respectively. A tomographic phantom study demonstrated that spheres with a diameter of 20 mm were well resolved when filled with 18F activity and placed inside a water-filled phantom. CONCLUSION: The triple-headed SPECT camera in this investigation is a practical means of acquiring tomographic 18F images. The reconstructed slices were of sufficient quality to be of value in some clinical studies.
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Radioisótopos de Flúor , Procesamiento de Imagen Asistido por Computador , Tomografía Computarizada de Emisión de Fotón Único , Cámaras gamma , Humanos , Modelos Estructurales , Sensibilidad y Especificidad , Tomografía Computarizada de Emisión de Fotón Único/instrumentación , Tomografía Computarizada de Emisión de Fotón Único/métodosRESUMEN
Although ventilation-perfusion lung scanning is widely used in evaluating patients with suspected pulmonary embolus, additional rapid screening tests are needed to supplement scintigraphy in patients in whom the scan is indeterminate or the scan results are discordant with clinical suspicion. D-dimer is a fibrin degradation product which should be elevated in the presence of intravascular coagulation. We prospectively studied patients referred for lung scanning by obtaining a plasma D-dimer latex agglutination assay at the time of the scan. Of 64 patients who had pulmonary angiography to confirm the diagnosis, 16 were positive for pulmonary embolus and only one had a normal D-dimer. The D-dimer was normal in 27 of 48 patients without embolus and elevated in 21. Although an elevated D-dimer level is a nonspecific finding, we conclude that a normal D-dimer is a good negative predictor for pulmonary embolus, with a negative predictive value of 0.97.
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Productos de Degradación de Fibrina-Fibrinógeno/análisis , Pulmón/diagnóstico por imagen , Embolia Pulmonar/diagnóstico , Ensayo de Inmunoadsorción Enzimática , Humanos , Valor Predictivo de las Pruebas , Estudios Prospectivos , Arteria Pulmonar/diagnóstico por imagen , Embolia Pulmonar/sangre , Embolia Pulmonar/epidemiología , Radiografía , Cintigrafía , Sensibilidad y Especificidad , Agregado de Albúmina Marcado con Tecnecio Tc 99m , Relación Ventilacion-Perfusión/fisiología , Radioisótopos de XenónRESUMEN
UNLABELLED: The objective of this work was to develop patient-specific dosimetry for patients with metastatic gastrointestinal tract cancers who received 111In-CC49 IgG for imaging before therapy with 90Y-CC49 IgG. METHODS: Whole-body imaging of 12 patients, who received 111-185 MBq (3-5 mCi) of 111In-CC49, commenced in < 2 hr postinfusion and was continued daily for 4-5 days. SPECT data were acquired at 24 and 72 hr to determine the range of 111In-CC49 activity concentrations in tumors and normal organs. Time-activity curves were generated from the image data and scaled from 111In-CC49 to 90Y-CC49 for dosimetric purposes. Absorbed-dose calculations for 90Y-CC49 included the mean and range in tumor and normal organs. Computed 90Y-CC49 activity concentrations were compared with measurements on 10 needle biopsies of normal liver and four tumor biopsies. RESULTS: In 9 of 10 normal liver samples, the range of computed 90Y-CC49 activity concentrations bracketed measured values. This was also the case for 3 of 4 tumor biopsies. Absorbed-dose calculations for 90Y-CC49 were based on patients' images and activities in tissue samples and, hence, were patient-specific. CONCLUSION: For the radiolabeled antibody preparations used in this study, quantitative imaging of 111In-CC49 provided the data required for 90Y-CC49 dosimetry. The range of activities in patients' SPECT images was determined for a meaningful comparison of measured and computed values. Knowledge of activity distributions in tumors and normal organs was essential for computing mean values and ranges of absorbed dose and provided a more complete description of the absorbed dose from 90Y-CC49 than was possible with planar methods.
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Anticuerpos Monoclonales , Neoplasias Gastrointestinales/diagnóstico por imagen , Neoplasias Gastrointestinales/radioterapia , Radioisótopos de Indio , Radioinmunoterapia , Radioisótopos de Itrio/uso terapéutico , Absorción , Anciano , Antígenos de Neoplasias/inmunología , Femenino , Neoplasias Gastrointestinales/secundario , Glicoproteínas/inmunología , Semivida , Humanos , Radioisótopos de Indio/farmacocinética , Hígado/efectos de la radiación , Masculino , Persona de Mediana Edad , Dosificación Radioterapéutica , Bazo/efectos de la radiación , Tomografía Computarizada de Emisión de Fotón Único , Radioisótopos de Itrio/farmacocinéticaRESUMEN
UNLABELLED: The emphasis of radiolabeled iododeoxyuridine (*IUdR) research at our institution to date has been to assess its safety as a potential therapeutic agent. Toward this goal, we have performed preclinical and clinical studies, using various routes of administration, to detect adverse changes in normal tissues in both humans and animals. As IUdR is rapidly dehalogenated by the liver, the intravenous route is unlikely to be successful in therapeutic efforts. We have therefore focused our attention on more "protected" routes: intra-arterial and intravesicular administration. METHODS: Studies were performed in farm pigs after multiple administrations of [125I]IUdR into the aorta, carotid artery and bladder. IUdR and metabolites were measured in venous blood samples at appropriate time intervals after administration, after which histologic examination of tissues was performed. Studies in human have been performed after intra-arterial administration of [123I]IUdR in patients with liver metastases and intravesicular administration in patients with bladder carcinoma, initially using [123I]IUdR and currently using both [123I]IUdR and [125I]IUdR. Blood samples for pharmacokinetics and metabolite analysis and tissue for autoradiography (when feasible) have been obtained. RESULTS: To date, no evidence of adverse effects on normal tissue or alteration of hematologic or metabolic indices have been seen in pigs or humans. When instilled in the bladder, there is little leakage of IUdR in the circulation. CONCLUSION: When [125I]IUdR is used as a therapeutic agent, we anticipate little or no effect on normal tissues.
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Idoxuridina/toxicidad , Radioisótopos de Yodo/toxicidad , Administración Intravesical , Animales , Femenino , Humanos , Idoxuridina/administración & dosificación , Idoxuridina/uso terapéutico , Inyecciones Intraarteriales , Radioisótopos de Yodo/administración & dosificación , Radioisótopos de Yodo/uso terapéutico , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/secundario , Masculino , Porcinos , Neoplasias de la Vejiga Urinaria/radioterapiaRESUMEN
A method employing stable isotope labeling and fast-atom bombardment (FAB) tandem mass spectrometry has been developed to directly assess events of biosynthesis and metabolism of arachidonic acid containing phospholipid molecular species by cells carried in culture. Mast cells, cultured with [(13)C]linoleic acid, converted this precursor into arachidonic acid which was then incorporated into cellular phospholipids. Over a 24 hour period, the extent of label enrichment in each arachidonate-containing phospholipid molecular species was monitored by using negative FAB ionization with selected reaction monitoring. Specific incorporation of [(13)C17] labeled arachidonate was determined from the ratio of the carboxylate anions at m/z 320 and 303, which correspond to [(13)C17]arachidonate and unlabeled arachidonate, respectively, produced by collision-induced dissociation of each specific molecular anion. The use of [(13)C]linoleic acid as a precursor of arachidonic acid avoids the problem of changing the endogenous pool size by directly adding labeled arachidonic acid. Measurement of the [(13)C17]label also avoids interferences from endogenous isobaric fatty acids that are naturally present at low levels.
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The analysis of 1-hexadecyl-2-acetyl-glycerophosphocholine (platelet activating factor, PAF) by negative ion and normal-phase liquid chromatography/tandem mass spectrometry (LC/MS/MS) was investigated as an alternative technique to the currently used gas chromatography/MS and positive ion LC/MS/MS procedures. The positive ion [M + H]+ derived from PAF and generated by electrospray ionization is abundant, but the potential presence of isobaric 1-octadecanoyl-2-lyso-glycerophosphocholine (stearoyl-lyso-GPC) and 1-hexadecanoyl-2-formyl-glycerophosphocholine (PFPC) in biological samples limits the use of the most abundant collision-induced decomposition (CID) transition (formation of the phosphocholine ion, m/z 524-->184) if chromatographic separation is not achieved. Less abundant CID product ions, such as loss of the neutral ketene molecule derived from the respective fatty acyl groups, provide the requisite specificity, but the intensity of these transitions yields a signal-to-noise ratio that greatly diminishes the analytical sensitivity. With negative ion LC/MS/MS, however, the molecular anions [M - 15]- derived from PAF, stearoyl-lyso-GPC and PFPC decompose to the carboxylate anions at m/z 59, 283 and 255, respectively, permitting discrimination of these isobaric molecules even without chromatographic separation. In addition, the CID of [M - 15]- was favorable, yielding ion currents of sufficient intensity to permit the measurement of PAF when isolated from small quantities of biological material. With the use of a stable isotopically labeled variant of PAF and isotope dilution, negative ion LC/MS/MS was found to measure PAF reliably even in the presence of the isobaric stearoyl-lyso-GPC and permitted the use of non-chlorinated mobile phases for normal-phase high-performance LC.
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Espectrometría de Masas , Factor de Activación Plaquetaria/química , Humanos , Espectrometría de Masas/métodosRESUMEN
Oxidized low-density lipoprotein (LDL) is thought to play an important role in atherogenesis and cardiovascular disease in humans. Oxidized LDL is a complex mixture of many oxidized species, including numerous oxidized glycerophospholipids. Electrospray ionization and tandem mass spectrometry as well as microchemical derivatization of high-performance liquid chromatographically purified fractions derived from oxidized LDL were investigated as means to determine the structure of individual components present in oxidized LDL. One major oxidized phosphocholine lipid had an [M + H](+) ion at m/z 650. Derivatization to the trimethylsilyl ether and methoxime caused shifts in mass which, along with negative ion collision-induced dissociation mass spectra, were consistent with the presence of three species, 1-palmitoyl-2-(9-oxononanoyl)glycerophosphocholine and two isomeric 1-octadecanoyl-2-(hydroxyheptenoyl)glycerophosphocholines. These species were chemically synthesized. Trimethylsilylation of free hydroxyl groups increased the mass of the phospholipid acyl chains containing hydroxyl groups by 72 u. Conversion of carbonyl groups to the methoxylamine derivative increased the mass by 29 u. Ozonolysis of those products which contained double bonds proved to be a facile technique to determine the position and number of double bonds present. The use of these techniques was illustrated in the structural characterization of one major component (m/z 650, positive ions) in oxidized LDL as 1-octadecanoyl-2-(7-hydroxyhepta-5-enoyl)glycerophosphocholi ne. A possible mechanism for the formation of this unique chain-shortened glycerophospholipid is proposed.
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Glicerilfosforilcolina/análisis , Fosfolípidos/análisis , Cromatografía Líquida de Alta Presión , Humanos , Hidrólisis , Indicadores y Reactivos , Lipoproteínas LDL/análisis , Espectrometría de Masas , Metoxamina/química , Oxidación-Reducción , Ozono/química , Espectrofotometría Ultravioleta , Compuestos de Trimetilsililo/químicaRESUMEN
Estimates of maternal deaths per 100,000 births are 270 for Latin America, 420 for Asia and 640 for Africa, compared to only 30 in developed countries. In places with high maternal death rates, women who fail to receive antenatal care and who then report to hospital only when their lives are threatened by major obstetric complications constitute the crux of the problem. In reducing maternal deaths in such places, especially in Africa, the need is to provide vigorous treatment for the unbooked emergencies and, at the same time, work towards the removal of the cultural, health and socio-economic conditions which create the unbooked emergencies. The first objective can be achieved through developing a network of first referral hospitals so that life saving measures are accessible to all who need them before it is too late. The second objective can be realized only through the universal provision and utilization of basic but professional antenatal care and also through modernization of the society as a whole. For all of these goals, universal formal education is fundamental.
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Complicaciones del Embarazo/mortalidad , África/epidemiología , Agentes Comunitarios de Salud , Servicios de Planificación Familiar , Femenino , Hospitalización , Humanos , Mortalidad Materna , Aceptación de la Atención de Salud , Embarazo , Atención Prenatal , Factores Socioeconómicos , Clima TropicalRESUMEN
Antibodies against a variety of tumor-associated antigens have been studied, as well as a number of modifications to the antibodies themselves, including Fab' fragments and chimeric, humanized, and human antibodies. The appropriate use of radioimmunoconjugates in the evaluation of cancer patients has not yet been clearly defined. Only a few studies have assessed their use, primarily through the intravenous route, in initial disease staging. To date, immunolymphoscintigraphy has not proven promising in the staging of cancers. More emphasis has been given to the use of IV radioimmunoconjugates to detect residual and recurrent disease, with generally favorable results. In addition, radioimmunoguided surgery, using small, handheld probes to detect foci of antibody accumulation, appears to be a valuable tool. As better production techniques become available and large clinical trials provide more clearly defined indications for radioimmunoconjugate use, these agents should enter the arena for routine diagnostic use.
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Anticuerpos Antineoplásicos , Antígenos de Neoplasias/inmunología , Neoplasias/diagnóstico por imagen , Radioinmunodetección , Anticuerpos Monoclonales , Humanos , Radioisótopos de Indio , Oligopéptidos , Ácido Pentético/análogos & derivadosRESUMEN
Protons of a specific energy, 55 MeV, have been found to induce primary high grade astrocytomas (HGA) in the Rhesus monkey (Macaca mulatta). Brain tumors of this type were not induced by protons of other energies (32-2,300 MeV). Induction of HGA has been identified in human patients who have had radiation therapy to the head. We believe that the induction of HGA in the monkey is a consequence of dose distribution, not some unique "toxic" property of protons. Comparison of the human experience with the monkey data indicates the RBE for induction of brain tumors to be about one. It is unlikely that protons cause an unusual change in oncogenic expression, as compared to conventional electromagnetic radiation.
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Astrocitoma/etiología , Neoplasias Inducidas por Radiación , Protones , Radiación Ionizante , Animales , Relación Dosis-Respuesta en la Radiación , Ependimoma/etiología , Humanos , Macaca mulatta , Dosis de Radiación , Efectividad Biológica RelativaRESUMEN
A correlational analysis was conducted to assess the relationship among various assessment instruments, including Kagan, Rosman, Day, Albert, and Phillips's (1964) Matching Familiar Figures Test (MFFT), and actual classroom performance vis-à-vis impulsive responding. Subjects were 22 children (16 male, 6 female), ages 5 to 11 years, enrolled in an academic remediation program. The results do not support a relationship between impulsivity, as measured by the MFFT, and academic progress in a classroom setting. Implications for task-specific measures of impulsivity and remediation are discussed.
Asunto(s)
Conducta Impulsiva/psicología , Discapacidades para el Aprendizaje/psicología , Logro , Atención , Niño , Preescolar , Educación Especial , Femenino , Humanos , Conducta Impulsiva/diagnóstico , Discapacidades para el Aprendizaje/diagnóstico , Masculino , Tiempo de ReacciónRESUMEN
PIP: Serial observations have been made on the total and differential leucocyte counts of Nigerian primigravidae during pregnancy and the puerperium, and of their newborn infants. There was a neutrophil leucocytosis of double non-pregnant values during the 2nd and 3rd trimesters, and a peak during labor. The total white cell and neutrophil counts behaved in a manner similar to that reported in Caucasians, but counts were on average about 3.0 x 1 billionth 1 lower in the Nigerians. Eosinophil counts were high, presumably due to helminthic infections, but were lower in pregnancy than in non-pregnant state: there was a dramatic lowering of the eosinophil count at the time of delivery. Visual counting did not allow meaningful observations on changes in the basophil count. Monocyte counts were unaltered by pregnancy, but there was a significant drop in mean count caused by a great number of 0 differential counts at delivery. There was a slight but significant depression of lymphocyte count during pregnancy, but no further change at the time of delivery. All counts at 6 weeks after delivery were similar to those of adult male Nigerians. The leucocyte counts of African and Caucasian newborn appear to be similar. The data provide reference ranges of white cell counts in African or women of African descent during pregnancy.^ieng