RESUMEN
PURPOSE: Older cancer survivors required medical care during the COVID-19 pandemic, but there are limited data on medical care in this age group. METHODS: We evaluated care disruptions in a longitudinal cohort of non-metastatic breast cancer survivors aged 60-98 from five US regions (n = 321). Survivors completed a web-based or telephone survey from May 27, 2020 to September 11, 2020. Care disruptions included interruptions in seeing or speaking to doctors, receiving medical treatment or supportive therapies, or filling prescriptions since the pandemic began. Logistic regression models evaluated associations between care disruptions and education, medical, psychosocial, and COVID-19-related factors. Multivariate models included age, county COVID-19 death rates, comorbidity, and post-diagnosis time. RESULTS: There was a high response rate (n = 262, 81.6%). Survivors were 32.2 months post-diagnosis (SD 17.5, range 4-73). Nearly half (48%) reported a medical disruption. The unadjusted odds of care disruptions were higher with each year of education (OR 1.22, 95% CI 1.08-1.37, p = < 0.001) and increased depression by CES-D score (OR 1.04, CI 1.003-1.08, p = 0.033) while increased tangible support decreased the odds of disruptions (OR 0.99, 95% CI 0.97-0.99, p = 0.012). There was a trend between disruptions and comorbidities (unadjusted OR 1.13 per comorbidity, 95% CI 0.99-1.29, p = 0.07). Adjusting for covariates, higher education years (OR1.23, 95% CI 1.09-1.39, p = 0.001) and tangible social support (OR 0.98 95% CI 0.97-1.00, p = 0.006) remained significantly associated with having care disruptions. CONCLUSION: Older breast cancer survivors reported high rates of medical care disruptions during the COVID-19 pandemic and psychosocial factors were associated with care disruptions. CLINICALTRIALS. GOV IDENTIFIER: NCT03451383.
Asunto(s)
Neoplasias de la Mama , COVID-19 , Supervivientes de Cáncer , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/terapia , Femenino , Humanos , Persona de Mediana Edad , Pandemias , SARS-CoV-2RESUMEN
Pathogen burden is a construct developed to assess the cumulative effects of multiple, persistent pathogens on morbidity and mortality. Despite the likely biological wear and tear on multiple body systems caused by persistent infections, few studies have examined the impact of total pathogen burden on such outcomes and specifically on preclinical markers of dysfunction. Using data from two waves of the National Health and Nutrition Examination Survey, we compared three alternative methods for measuring pathogen burden, composed of mainly persistent viral infections, using a cumulative deficits index (CDI) as an outcome: single pathogen associations, a pathogen burden summary score and latent class analyses. We found significant heterogeneity in the distribution of the CDI by age, sex, race/ethnicity and education. There was an association between pathogen burden and the CDI by all three metrics. The latent class classification of pathogen burden showed particularly strong associations with the CDI; these associations remained after controlling for age, sex, body mass index, smoking, race/ethnicity and education. Our results suggest that pathogen burden may influence early clinical indicators of poor health as measured by the CDI. Our results are salient since we were able to detect these associations in a relatively young population. These findings suggest that reducing pathogen burden and the specific pathogens that drive the CDI may provide a target for preventing the early development of age-related physiological changes.
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Infecciones Bacterianas/complicaciones , Infecciones Bacterianas/epidemiología , Enfermedad Crónica/epidemiología , Enfermedad Crónica/mortalidad , Virosis/complicaciones , Virosis/epidemiología , Adulto , Bacterias/aislamiento & purificación , Infecciones Bacterianas/microbiología , Infecciones Bacterianas/mortalidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Estados Unidos/epidemiología , Virosis/mortalidad , Virosis/virología , Virus/aislamiento & purificación , Adulto JovenRESUMEN
PURPOSE: We examined acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) events among 9679 women treated for breast cancer on four adjuvant Alliance for Clinical Trials in Oncology trials with >90 months of follow-up in order to better characterize the risk for AML/MDS in older patients receiving anthracyclines. METHODS: We used multivariable Cox regression to examine factors associated with AML/MDS, adjusting for age (≥65 vs. <65 years; separately for ≥70 vs. <70 years), race/ethnicity, insurance, performance status, and anthracycline receipt. We also examined the effect of cyclophosphamide, the interaction of anthracycline and age, and outcomes for those developing AML/MDS. RESULTS: On Cancer and Leukemia Group B (CALGB) 40101, 49907, 9344, and 9741, 7290 received anthracyclines; 15% were in the age ≥65 and 7% were ≥70. Overall, 47 patients developed AML/MDS (30 AML [0.3%], 17 MDS [0.2%]); 83% of events occurred within 5 years of study registration. Among those age ≥65 and ≥70, 0.8 and 1.0% developed AML/MDS (vs. 0.4% for age <65), respectively. In adjusted analyses, older age and anthracycline receipt were significantly associated with AML/MDS (adjusted hazard ratio [HR] for age ≥65 [vs. <65] = 3.13, 95% confidence interval [CI] 1.18-8.33; HR for anthracycline receipt [vs. no anthracycline] = 5.16, 95% CI 1.47-18.19). There was no interaction between age and anthracycline use. Deaths occurred in 70% of those developing AML/MDS. CONCLUSIONS: We observed an increased risk for AML/MDS for older patients and those receiving anthracyclines, though these events were rare. Our results help inform discussions surrounding anticipated toxicities of adjuvant chemotherapy in older patients.
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Neoplasias de la Mama/complicaciones , Neoplasias de la Mama/epidemiología , Leucemia Mieloide Aguda/epidemiología , Leucemia Mieloide Aguda/etiología , Síndromes Mielodisplásicos/epidemiología , Síndromes Mielodisplásicos/etiología , Neoplasias Primarias Secundarias , Factores de Edad , Anciano , Anciano de 80 o más Años , Antraciclinas/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias de la Mama/tratamiento farmacológico , Quimioterapia Adyuvante/efectos adversos , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Riesgo , Factores de TiempoRESUMEN
BACKGROUND: Two Cancer and Leukemia Group B (CALGB) studies were utilized to determine the efficacy and tolerability of paclitaxel (Taxol) in older patients with metastatic breast cancer. PATIENTS AND METHODS: CALGB 9840 evaluated weekly paclitaxel (80 mg/m(2)) versus paclitaxel every 3 weeks (175 mg/m(2)); CALGB 9342 evaluated three doses of paclitaxel as follows: 175, 210 and 250 mg/m(2) each over 3 h every 3 weeks. Of the 1048 patients, paclitaxel was used first line in 57%. The groups: (i) <55 years (45%), (ii) 55-64 years (29%), and (iii) ≥65 years (26%). RESULTS: Tumor response was also similar among age groups. First-line therapy (P = 0.0001) and better performance status (PS) (P = 0.018) were significantly related to higher response. Age did not significantly relate to overall survival (OS) or progression-free survival (PFS). First-line therapy, better PS, estrogen receptor positive status and a fewer number of metastatic sites were significantly related to improved OS and PFS. The grade ≥3 toxic effects that increased linearly with age were leucopenia (P = 0.0099), granulocytopenia (P = 0.022), anorexia (P = 0.028), bilirubin elevation (P = 0.0035) and neurotoxicity (P < 0.0001). Patients over 65 years receiving second-line therapy had the shortest time to neurotoxicity. CONCLUSIONS: Older women with breast cancer derive similar efficacy from treatment with paclitaxel as younger women. Older women are at increased risk for specific toxic effects.
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Antineoplásicos/efectos adversos , Neoplasias de la Mama/tratamiento farmacológico , Paclitaxel/efectos adversos , Adulto , Factores de Edad , Anciano , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Supervivencia sin Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Persona de Mediana Edad , Metástasis de la Neoplasia , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios RetrospectivosRESUMEN
BACKGROUND: Cyclophosphamide-methotrexate-5-fluorouracil (CMF) is often selected as adjuvant chemotherapy for older patients with early-stage breast cancer due to perceived superior tolerability. We sought to measure persistence with CMF, adherence to oral cyclophosphamide, and the association of these with toxic effects. PATIENTS AND METHODS: CALGB 49907 was a randomized trial comparing standard chemotherapy (CMF or AC, provider/patient choice) with capecitabine in patients aged ≥65 with stage I-IIIB breast cancer. Those randomized to standard therapy and choosing CMF were prescribed oral cyclophosphamide 100 mg/m(2) for 14 consecutive days in six 28-day cycles. Persistence was defined as being prescribed six cycles of at least one of the three CMF drugs. Adherence was the number of cyclophosphamide doses that women reported they had taken divided by the number prescribed. Persistence and adherence were based on case report forms and medication calendars. RESULTS: Of 317 randomized to standard chemotherapy, 133 received CMF. Median age was 73 (range 65-88). Seventy-one percent submitted at least one medication calendar; 65% persisted with CMF. Non-persistence was associated with node negativity (P = 0.019), febrile neutropenia (P = 0.002), and fatigue (P = 0.044). Average adherence was 97% during prescribed cycles. CONCLUSIONS: Self-reported adherence to cyclophosphamide was high, but persistence was lower, which may be attributable to toxic effects.
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Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Cumplimiento de la Medicación , Cooperación del Paciente , Factores de Edad , Anciano , Anciano de 80 o más Años , Capecitabina , Quimioterapia Adyuvante/efectos adversos , Ciclofosfamida/efectos adversos , Ciclofosfamida/uso terapéutico , Desoxicitidina/efectos adversos , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapéutico , Femenino , Fluorouracilo/efectos adversos , Fluorouracilo/análogos & derivados , Fluorouracilo/uso terapéutico , Humanos , Metotrexato/efectos adversos , Metotrexato/uso terapéuticoRESUMEN
PurposeOlder cancer survivors required medical care during the COVID-19 pandemic despite infection risks, but there are limited data on medical care in this age group. METHODS: We evaluated care disruptions in a longitudinal cohort of non-metastatic breast cancer survivors ages 60-98 from five US regions (n=321). Survivors completed a web-based or telephone survey from May 27, 2020 to September 11, 2020. Care disruptions included self-reported interruptions in ability to see doctors, receive treatment or supportive therapies, or fill prescriptions. Logistic regression models evaluated bivariate and multivariate associations between care disruptions and education, medical, psychosocial and COVID-19-related factors. Multivariate models included age, county COVID-19 rates, comorbidity and post-diagnosis time. RESULTS: There was a high response rate (n=262, 81.6%). Survivors were 32.2 months post-diagnosis (SD 17.5, range 4-73). Nearly half (48%) reported a medical disruption. The unadjusted odds of care disruptions were significantly higher with more education (OR 1.23 per one-year increase, 95% CI 1.09-1.39, p =0.001) and greater depression (OR 1.04 per one-point increase in CES-D score, CI 1.003-1.08, p=0.033); tangible support decreased the odds of disruptions (OR 0.99, 95% CI 0.97-0.99 per one-point increase, p=0.012). There was a trend for associations between disruptions and comorbidity (unadjusted OR 1.13 per 1 added comorbidity, 95% CI 0.99-1.29, p=0.07). Adjusting for covariates, only higher education (p=0.001) and tangible social support (p=0.006) remained significantly associated with having care disruptions. CONCLUSIONS: Older breast cancer survivors reported high rates of medical care disruptions during the COVID-19 pandemic and psychosocial factors were associated with care disruptions.
RESUMEN
We describe a newly recognized 40 kD FcR for IgG on human neutrophilic granulocytes. An mAb (IV3) developed against the IgG FcR of K562 cells, and specific as well for a 40 kD FcR on human monocytes and platelets, was found to purify by affinity adsorption a 40 kD protein from detergent lysates of surface-radioiodinated neutrophils. This protein, proteolytically degraded to 33 kD when purified in the absence of diisopropylfluorophosphate, is distinct from the 51-73 kD protein precipitated by the anti-neutrophil FcR mAb, 3G8, previously described by others. Complete inhibition of binding of rabbit IgG-coated erythrocytes to neutrophils was achieved only when both antibodies, IV3 and 3G8, were used. Fab fragments of IV3 were as effective inhibitors as the intact molecule. IV3 IgG or Fab fragments completely and selectively inhibited immune complex-mediated generation of superoxide by human neutrophils; superoxide generation by other stimulants was not abrogated by IV3. This antibody (IV3) bound also to human eosinophils and completely inhibited the binding of IgG-coated erythrocytes to eosinophils. IV3 appears to define the human homolog of the murine macrophage FcRII identified initially by mAb 2.4G2 and present in the mouse on both neutrophils and eosinophils.
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Inmunoglobulina G/análisis , Neutrófilos/metabolismo , Receptores Fc/análisis , Anticuerpos Monoclonales , Complejo Antígeno-Anticuerpo , Eosinófilos/metabolismo , Citometría de Flujo , Humanos , Fragmentos Fab de Inmunoglobulinas/farmacología , Formación de Roseta , Superóxidos/metabolismoRESUMEN
BACKGROUND: Disparities in adult morbidity and mortality may be rooted in patterns of biological dysfunction in early life. We sought to examine the association between pathogen burden and a cumulative deficits index (CDI), conceptualized as a pre-clinical marker of an unhealthy biomarker profile, specifically focusing on patterns across levels of social disadvantage. METHODS: Using the data from the National Health and Nutrition Examination Survey 2003-2004 wave (aged 20-49 years), we examined the association of pathogen burden, composed of seven pathogens, with the CDI. The CDI comprised 28 biomarkers corresponding to available clinical laboratory measures. Models were stratified by race/ethnicity and education level. RESULTS: The CDI ranged from 0.04 to 0.78. Nearly half of Blacks were classified in the high burden pathogen class compared with 8% of Whites. Among both Mexican Americans and other Hispanic groups, the largest proportion of individuals were classified in the common pathogens class. Among educational classes, 19% of those with less than a high school education were classified in the high burden class compared with 7% of those with at least a college education. Blacks in the high burden pathogen class had a CDI 0.05 greater than those in the low burden class (P < 0.05). Whites in the high burden class had a CDI only 0.03 greater than those in the low burden class (P < 0.01). DISCUSSION: Our findings suggest there are significant social disparities in the distribution of pathogen burden across race/ethnic groups, and the effects of pathogen burden may be more significant for socially disadvantaged individuals.
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Patógenos Transmitidos por la Sangre/aislamiento & purificación , Escolaridad , Etnicidad/estadística & datos numéricos , Disparidades en el Estado de Salud , Encuestas Epidemiológicas/estadística & datos numéricos , Grupos Raciales/estadística & datos numéricos , Adulto , Biomarcadores/sangre , Femenino , Encuestas Epidemiológicas/métodos , Humanos , Laboratorios , Masculino , Persona de Mediana Edad , Pobreza/estadística & datos numéricos , Factores Socioeconómicos , Estados Unidos , Adulto JovenRESUMEN
A continuous tissue culture cell line (Karpas line 120), derived from a patient with acute myeloblastic leukemia, not only demonstrates myeloblastic morphology and in vitro expression of several myeloid-specific biochemical markers but also contains Epstein-Barr virus (EBV) nuclear antigen. The present studies demonstrate EBV-genome-specific DNA within the total cellular DNA by molecular hybridization, thus establishing the presence of stable viral genome integration. The cells demonstrate complex coordinated myeloid functions including ingestion, degranulation, and respiratory burst activity. Line 120 cells show a respiratory burst (superoxide and hydrogen peroxide generation and hexosemonophosphate shunt activity) in response to soluble (phorbol myristate acetate) and particulate (latex beads) stimuli, as do normal granulocytes. They ingest complement-opsonized particles (lipopolysaccharide-oil droplets, zymosan, and bacteria), and degranulate in response to them. However, unlike normal granulocytes, the line 120 cells do not demonstrate respiratory burst activity in response to these complementopsonized particles. The dissociation between ingestion of complement-opsonized particles and activation of oxygen-dependent bactericidal activity severely impairs bacterial killing as compared with normal polymorphonuclear phagocytes.
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Transformación Celular Viral , Herpesvirus Humano 4 , Leucemia Mieloide Aguda/fisiopatología , Consumo de Oxígeno , Fagocitosis , Animales , Actividad Bactericida de la Sangre , Línea Celular , ADN Viral/análisis , Herpesvirus Humano 4/genética , Hexosafosfatos/metabolismo , Peróxido de Hidrógeno/metabolismo , Leucemia Experimental/fisiopatología , Superóxidos/metabolismoRESUMEN
Polar solvents induce terminal differentiation in the human promyelocytic leukemia cell line HL-60. The present studies describe the functional changes that accompany the morphologic progression from promyelocytes to bands and poly-morphonuclear leukocytes (PMN) over 9 d of culture in 1.3 percent dimethylsulfoxide (DMSO). As the HL-60 cells mature, the rate of O(2-) production increase 18-fold, with a progressive shortening of the lag time required for activation. Hexosemonophosphate shunt activity rises concomitantly. Ingestin of paraffin oil droplets opsonized with complement or Ig increases 10-fold over 9 d in DMSO. Latex ingestion per cell by each morphologic type does not change significantly, but total latex ingestion by groups of cells increases with the rise in the proportion of mature cells with greater ingestion capacities. Degranulation, as measured by release of beta-glucuronidase, lysozyme, and peroxidase, reaches maximum after 3-6 d in DMSO, then declines. HL-60 cells contain no detectable lactoferrin, suggesting that their secondary granules are absent or defective. However, they kill staphylococci by day 6 in DMSO. Morphologically immature cells (days 1-3 in DMSO) are capable of O(2-) generation, hexosemonophosphate shunt activity, ingestion, degranulation, and bacterial killing. Maximal performance of each function by cells incubated in DMSO for longer periods of time is 50-100 percent that of normal PMN. DMSO- induced differentiation of HL-60 cells is a promising model for myeloid development.
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Diferenciación Celular/efectos de los fármacos , Dimetilsulfóxido/farmacología , Leucemia Mieloide Aguda/patología , Lisosomas/enzimología , Línea Celular , Humanos , Neutrófilos/fisiología , Oxidación-Reducción , Fagocitosis , Superóxidos/metabolismoRESUMEN
The phenomenon of redistribution of surface membrane immunoglobulin (Ig) components (capping) has been well described in mouse lymphoid cells. The characteristics of this process in human lymphocytes are less clear. This study characterizes the phenomenon of surface membrane Ig redistribution of normal and chronic lymphocytic leukemia (CLL) lymphocytes with the use of fluoroscein-labeled anti-Ig sera. Normal lymphocytes underwent rapid cap formation after incubation with anti-Ig serum in the cold and subsequent rewarming. The morphology was characteristic with aggregation over the pole of the cell opposite the nucleus and over the uropod when present. The process was energy dependent but independent of protein synthesis, and could be inhibited by vincristine, vinblastine, and colchicine but not by cytochalasin B. CLL cells, on the other hand, though showing fluorescent complex aggregation on the surface, rarely demonstrated unidirectional movement of these aggregates to form a cap. Cap formation in these cells could not be stimulated by supplementing the energy source or protein concentration of the medium nor by adding glutamic acid which could partially reverse the vincristine and vinblastine inhibition of normal capping. The failure of agents which inhibit motility to inhibit capping of the normal lymphocytes suggests that active locomotion is not a direct prerequisite for capping. The results also suggest the involvement of microtubules in normal capping and the possibility that abnormal membrane structure or microtubular function could explain the failure of CLL cells to behave normally in this regard. The role of this cellular defect in the immune deficiencies exhibited by many patients with CLL, however, is not established.
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Inmunoglobulinas , Leucemia Linfoide/inmunología , Linfocitos/inmunología , Animales , Anticuerpos Antiidiotipos , Azidas/farmacología , Bovinos , Membrana Celular/efectos de los fármacos , Membrana Celular/inmunología , Supervivencia Celular/efectos de los fármacos , Colchicina/farmacología , Medios de Cultivo , Cianuros/farmacología , Citocalasina B/farmacología , Depresión Química , Fluoresceínas , Técnica del Anticuerpo Fluorescente , Glutamatos/farmacología , Humanos , Leucemia Linfoide/sangre , Linfocitos/efectos de los fármacos , Microscopía Fluorescente , Puromicina/farmacología , Tiocianatos , Factores de Tiempo , Alcaloides de la Vinca/farmacologíaRESUMEN
Stimulation of guinea pig granolocytes by digitonin results in superoxide (O-2) generation. A continuous assay shows that there is a lag between the addition of digitonin and the onset of O-2 production. The rate of activation of the O-2 generating system is dependent upon the concentration of digitonin and the temperature. The final linear rate of O-2 production is affected by the concentration of digitonin, temperature, pH, and the presence of exogenous reduced pyridine nucleotides. Thus, factors which alter either the activation process or the activity of the O-2 generating system can affect O-2 production by stimulated granolocytes.
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Glicósidos Digitálicos/farmacología , Digitonina/farmacología , Granulocitos/metabolismo , Leucocitos/metabolismo , Oxígeno/biosíntesis , Superóxidos/biosíntesis , Animales , Grupo Citocromo c/metabolismo , Detergentes/farmacología , Cobayas , Peróxido de Hidrógeno/metabolismo , Concentración de Iones de Hidrógeno , Cinética , Masculino , NAD/farmacología , NADP/farmacología , Superóxido Dismutasa/metabolismo , TemperaturaRESUMEN
Erythrocytes coated with varying amounts of human complement were used to detect lymphocytes with complement receptors from normal subjects and patients with chronic lymphocytic leukemia. The relationship between the percentage of lymphocytes rosetting and the quantity of C3 present on complement-coated erythrocytes were studied. Small quantities of C3 (less than 5 fg/erythrocyte) caused maximal rosetting of normal lymphocytes. Maximal rosetting with chronic lymphocytic leukemia lymphocytes was not reached until much greater amounts of C3 were used to coat the erythrocytes. This difference in sensitivity to erythrocyte-bound complement was not due to an increased fraction of complement receptor-bearing cells in the leukemic patients. This loss of sensitivity of the chronic lymphocytic leukemia lymphocyte for complement may play a role in the immune deficiency present in this disease.
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Complemento C3 , Proteínas del Sistema Complemento , Leucemia Linfoide/inmunología , Linfocitos/inmunología , Membrana Celular/inmunología , Membrana Celular/metabolismo , Complemento C3/metabolismo , Complemento C3b/metabolismo , Proteínas del Sistema Complemento/metabolismo , Eritrocitos/inmunología , Humanos , Leucemia Linfoide/metabolismo , Linfocitos/metabolismo , Unión Proteica , Formación de RosetaRESUMEN
N-ethylmaleimide, divalent cations, ethylene glycol bis (beta aminoethyl ether) N,N,N',N',-tetraacetate, 2-deoxyglucose, cyanide, and dinitrophenol were examined for their effect on the ability of guinea pig granulocytes to generate superoxide (O(2) (-)) when stimulated by digitonin. N-ethylmaleimide (1 mM) inhibits only when added before complete activation of the O(2) (-) generating system, and at lower concentrations (0.05-0.2 mM) slows the activation process. Ca(++) is required for maximum O(2) (-) generation, and Mg(++) decreases the amount of Ca(++) required. Ethylene glycol bis (beta aminoethyl ether) N,N,N',N',-tetraacetate (10 mM) inhibits only if added before complete activation. Incubation of cells in 2-DOG causes a time- and concentration-dependent inhibition of O(2) (-) generation. It also increases the time required for activation of this system. Cyanide and dinitrophenol increase the rate of O(2) (-) production. However, when these compounds are added to cells whose O(2) (-) production is partially inhibited by incubation in 2-deoxyglucose, complete inhibition results. If cyanide or dinitrophenol is added after activation of 2-deoxyglucose-treated cells, no further inhibition occurs. On the basis of the above results, we conclude that the activation of the O(2) (-) generating system is N-ethylmaleimide sensitive, Ca(++) dependent, and energy requiring, but that the activity of the enzyme system in the cell is not.
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Metabolismo Energético , Granulocitos/metabolismo , Leucocitos/metabolismo , Oxígeno/biosíntesis , Superóxidos/biosíntesis , Animales , Líquido Ascítico/citología , Cationes Bivalentes/farmacología , Cianuros/farmacología , Digitonina/farmacología , Dinitrofenoles/farmacología , Metabolismo Energético/efectos de los fármacos , Etilmaleimida/farmacología , Cobayas , Macrófagos/metabolismo , Fagocitosis/efectos de los fármacos , Alveolos Pulmonares/citología , ConejosRESUMEN
Glutathione peroxidase (GSHPx) activity is an indicator of selenium status in selenium-deficient individuals. Utilizing polyclonal monospecific antibodies to purified erythrocyte GSHPx, we were able to determine the relationship between enzymatic activity and protein content. In erythrocytes from a selenium-deficient individual who was treated with selenium, and in HL-60 cells grown in the absence of selenium and then returned to selenium-containing medium, there was a direct relationship between enzymatic activity and protein content. Thus, selenium deficiency results not only in a decrease of GSHPx activity, but also in a decrease of GSHPx protein.
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Glutatión Peroxidasa/análisis , Selenio/deficiencia , Anticuerpos Monoclonales , Eritrocitos/enzimología , Humanos , Leucemia Mieloide Aguda/enzimologíaRESUMEN
Chronic granulomatous disease (CGD), an often fatal syndrome of recurrent infections results from the inability of patients' peripheral blood phagocytic leukocytes to generate superoxide despite otherwise normal phagocytic functions such as ingestion and degranulation. Circulating granulocytes and monocytes are the progeny of bone marrow progenitor cells, colony-forming units in culture. We compared the function of cells grown in two different in vitro cuture systems from the bone marrow of a CGD patient with those from normal subjects. The cells of normal colony-forming unit in culture colonies grown in semisolid medium reduced nitroblue tetrazolium dye when stimulated by phorbol myristate acetate; none of the cells from colonies derived from CGD marrow did so. Cells grown in liquid suspension culture from normal marrow generated superoxide nearly as well as normal peripheral blood granulocytes; those from CGD marrow produced no superoxide, similarly cultured cells from both normal and CGD marrow ingested opsonized bacteria at rates equal to peripheral blood granulocytes. CGD marrow-derived cells showed increased exocytic degranulation relative to both normal marrow-derived cells and normal peripheral blood granulocytes. These studies demonstrate that the basic functional characteristics of CGD are embedded in the genetic program of granulocyte progenitors.
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Enfermedad Granulomatosa Crónica/metabolismo , Células Madre Hematopoyéticas/metabolismo , Adolescente , Adulto , Actividad Bactericida de la Sangre , Células de la Médula Ósea , Células Cultivadas , Femenino , Humanos , Masculino , Nitroazul de Tetrazolio/metabolismo , Proteínas Opsoninas , Oxidación-Reducción , Superóxidos/metabolismo , Acetato de Tetradecanoilforbol/farmacología , Zimosan/farmacologíaRESUMEN
BACKGROUND: Abnormalities in taste and smell functioning occur with elevated frequency in both older adults and patients with cancer. With the predicted increase in both of these populations in the coming decades, it is imperative to evaluate potential interventions that are designed to help older cancer patients compensate for the additive burden of this disease and its treatment on age-related taste and smell losses. OBJECTIVE: The purpose of the current study was to determine if providing instruction and products for flavor enhancement of foods to elderly cancer patients in addition to nutritional information would improve their nutritional status, and, by extension, functional and immune status as well as quality of life. DESIGN: One hundred and seven subjects enrolled in the study. Fifty-four subjects were in the experimental group that received flavor enhancement plus nutritional information; fifty-three control subjects received only nutritional information. Subjects were evaluated 1 month, 3 months, and 8 months after beginning chemotherapy. At every session, subjects completed taste and smell assessments as well as questionnaires related to nutritional status, activities of daily living, and quality of life. Blood samples were also obtained to determine immune parameters. RESULTS: At the eight-month time point, experimental subjects had better scores on the mini nutritional assessment (MNA) and the physical function assessment of the quality of life questionnaire. Also at eight months, self-reported taste and smell perception for experimental subjects was better than that of controls as well as better than at earlier time points. Tests that assessed quantity and quality of food intake, as well as a number of immune parameters declined over time and did not differ significantly between groups. CONCLUSION: The combination of flavor enhancement, chemosensory education, and nutritional information for elderly cancer patients improved their nutritional assessment on the MNA and physical function over time. On the whole, experimental subjects perceived themselves to be better functioning at eight months than did their control counterparts.
Asunto(s)
Antineoplásicos/efectos adversos , Aromatizantes/uso terapéutico , Estado Nutricional , Trastornos del Olfato/terapia , Trastornos del Gusto/terapia , Actividades Cotidianas , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/tratamiento farmacológico , Femenino , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Masculino , Desnutrición/inducido químicamente , Desnutrición/terapia , Persona de Mediana Edad , Evaluación Nutricional , Trastornos del Olfato/inducido químicamente , Calidad de Vida , Olfato/fisiología , Gusto/fisiología , Trastornos del Gusto/inducido químicamente , Resultado del TratamientoRESUMEN
BACKGROUND: Treatment of tumor cells with hydroxyurea and other DNA-damaging agents has been shown to increase the experimental metastatic potential of these cells. PURPOSE: We sought to elucidate some of the biochemical and genetic changes that promote tumor cell metastasis in hydroxyurea-treated cells. We hypothesized that drug treatment induces resistance to oxidative damage and that elimination of this resistance reverses the drug-induced experimental metastatic capabilities of tumor cells. METHODS: We examined the effect of hydroxyurea treatment on B16 melanoma cells with respect to experimental metastatic potential, resistance to hydrogen peroxide (H2O2), glutathione peroxidase activity and messenger RNA (mRNA) level, glutathione reductase activity, glutathione levels, glutathione-S-transferase activity, and catalase activity and mRNA level. RESULTS: Hydroxyurea-treated cells were transiently more metastatic following intravenous injection in syngeneic mice and transiently more resistant than untreated cells to exogenous H2O2. Hydroxyurea-induced experimental metastases and H2O2 resistance were eliminated by depletion of intracellular glutathione with buthionine sulfoximine. Glutathione peroxidase activity and mRNA level, glutathione reductase activity, and reduced glutathione levels were all transiently increased in hydroxyurea-treated cells, whereas the increase in glutathione-S-transferase activity was sustained. Catalase activity was modestly increased with no increase in its mRNA levels. CONCLUSIONS: In B16 melanoma cells, experimental metastasis induced by hydroxyurea appears to depend on a process that requires glutathione. Hydroxyurea treatment also induces resistance to exogenous H2O2, which may be due to induction of glutathione and antioxidant enzyme activity. IMPLICATIONS: The role of antioxidants in B16 melanoma cells offers new insights into the metastatic process and the cellular response to chemotherapy.
Asunto(s)
Hidroxiurea/farmacología , Melanoma Experimental/patología , Metástasis de la Neoplasia , Animales , Butionina Sulfoximina , Catalasa/metabolismo , Femenino , Expresión Génica , Glutatión/metabolismo , Glutatión Peroxidasa/metabolismo , Glutatión Transferasa/metabolismo , Peróxido de Hidrógeno/metabolismo , Metionina Sulfoximina/análogos & derivados , Metionina Sulfoximina/farmacología , Ratones , Ratones Endogámicos C57BL , Oxidación-Reducción , ARN Mensajero/genética , ARN Neoplásico/metabolismoRESUMEN
We used the promyelocytic leukemic cell line HL-60 to explore the molecular mechanisms regulating stimulus-induced actin polymerization in myeloid cells. HL-60 cells express very few chemotactic peptide receptors in their undifferentiated state and fail to undergo actin polymerization when stimulated with the chemotactic peptide N-formyl-methionyl-leucyl-phenylalanine (FMLP). However, when the cells were induced to differentiate with dibutyryl cyclic AMP (dbcAMP) or retinoic acid, they acquired the ability to undergo actin polymerization on stimulation with FMLP or phorbol myristate acetate. Kinetic experiments revealed that in the first 48 h of retinoic acid treatment there was no increase in the chemotactic peptide receptors on HL-60 cells, but the cells were capable of undergoing actin polymerization on stimulation with FMLP. Similarly, treatment with dbcAMP showed no increase in chemotactic peptide receptors until 24 h but stimulus-induced actin polymerization was demonstrable as early as 4 h after the treatment. In addition, with dbcAMP-treated cells the magnitude of stimulus-induced actin polymerization showed large variation depending on the duration of exposure to the drug. Dual-label studies using propidium iodide to measure DNA content and NBD-phallacidin to measure the F-actin content revealed that these variations were not related to the stages of cell cycle. Cells in all stages of the cell cycle responded to stimulus-induced actin polymerization, but the magnitude of the response appeared to be more in cells in G2/M phase. The observations reported here indicate that the small number of chemotactic peptide receptors present on HL-60 cells are adequate to mount an actin polymerization response, provided the required intracellular mechanisms exist. Differentiation-inducing agents, therefore, must cause changes within the cell, such as induction of actin-binding proteins, to cause actin polymerization following FMLP stimulation. The HL-60 system serves as a useful model for studying the molecular mechanisms regulating stimulus-induced actin polymerization in human neutrophils.
Asunto(s)
Actinas/metabolismo , Bucladesina/farmacología , Leucemia Promielocítica Aguda/metabolismo , Receptores Inmunológicos/biosíntesis , Tretinoina/farmacología , Ciclo Celular , Diferenciación Celular/efectos de los fármacos , Humanos , Leucemia Promielocítica Aguda/patología , N-Formilmetionina Leucil-Fenilalanina/farmacología , Polímeros/metabolismo , Receptores de Formil Péptido , Células Tumorales CultivadasRESUMEN
L-Asparaginase (ASNase) is a potent antileukemic enzyme routinely used in the treatment of children with acute lymphoblastic leukemia. As part of investigations of the biological activity of ASNase, we have developed techniques which measure the in vitro and in vivo cell killing ability of ASNase. To study the effect of ASNase on in vitro survival of primary lymphoblasts, bone marrow mononuclear cells obtained from untreated patients with acute lymphoblastic leukemia were cultured with and without ASNase. After 5 days, viable cells were counted using trypan blue exclusion to calculate total cell kill due to ASNase. Propidium iodide exclusion, leukemia cell surface antigens, and flow cytometry were used to determine leukemia cell kill due to ASNase. Comparison of leukemia cell kill and total cell kill showed a direct linear relationship (n = 24, r = 0.7), preferential killing of leukemia cells by ASNase (slope = 0.66), and that use of leukemia cell surface markers yielded a more accurate measurement of leukemia cell killing. ASNase at concentrations from 0.0001 to 0.1 IU/ml had equal effects on extent of leukemia cell killing (P = 0.3 to 0.7), suggesting the absence of a dose response at the ASNase concentrations tested. As a measure of the in vivo response to ASNase treatment, the number of viable bone marrow leukemia cells in the patient prior to and 5 days after treatment with ASNase was measured as the product of (% of rhodamine 123 fluorescent [viable] cells) x (absolute leukemic infiltrate). The change which occurred in the viable leukemic infiltrate was the same for patients whether they received 25,000 or 2,500 IU/m2 of ASNase as a single drug. There was a linear correlation (n = 8, r = 0.9) between in vivo and in vitro leukemia cell killing by ASNase. Thus, the in vitro assay described here can be used to predict in vivo sensitivity to ASNase in acute lymphoblastic leukemia.