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1.
Artigo em Inglês | MEDLINE | ID: mdl-37164797

RESUMO

INTRODUCTION AND AIM: Hepatocellular carcinoma (HCC) is the third most frequent cancer of digestive tract tumors in Peru, with a high mortality rate of 17.7 per 100,000 inhabitants. A significant number of HCC cases in Peru do not follow the classic clinical epidemiology of the disease described in other parts of the world. Those patients present with a distinct transcriptome profile and a singular tumor process, suggesting a particular type of hepatocarcinogenesis in a portion of the Peruvian population. Our aim was to understand the clinical and biologic involvement of the epigenetic profile (methylation) and gene expression (transcriptome) of HCC in Peruvian patients. METHODS: HCC and liver transcriptome and DNA methylation profiles were evaluated in 74 Peruvian patients. RESULTS: When grouped by age, there was greater DNA methylation in younger patients with HCC but no differences with respect to the transcriptomic profile. A high prevalence of the hepatitis B virus (HBV) (>90%) was also observed in the younger patients with HCC. Enrichment analyses in both molecular profiles pinpointed PRC2 as an important molecular effector of that liver tumor process in Peruvian patients. CONCLUSION: HCC in Peruvian patients has a unique molecular profile, associated with the presence of HBV, as well as overall DNA hypermethylation related to undifferentiated liver cells or cellular reprogramming.

2.
Acta Ortop Mex ; 28(5): 305-9, 2014.
Artigo em Espanhol | MEDLINE | ID: mdl-26021095

RESUMO

Parosteal osteosarcoma originates on the surface of long bones and spares the medullary canal. Its peak incidence occurs in the third decade of life and it is more frequent in females than males. The juxtacortical variety of parosteal osteosarcoma is one of the most common ones, accounting for 1-6% of all osteosarcomas. The classical radiographic appearance of osteosarcoma includes high ossification density and a lobed mass, usually in the posterior aspect of the distal femur, sparing the medullary canal. We report herein the case of a 31 year-old male patient with a clinical picture that included left knee pain and who was seen as outpatient. He was started on treatment for enbloc resection of the tumor and implantation of the OSS (Orthopedic Salvage System) prosthesis. Treatment consisted of broad resection of the proximal tibia, of approximately 14 cm, as well as the implantation of a nonconventional modular tibial prosthesis. Both the radiographic and the clinical results were good and appropriate at the three week follow up.


Assuntos
Neoplasias Ósseas/cirurgia , Osteossarcoma/cirurgia , Próteses e Implantes , Tíbia , Adulto , Humanos , Masculino , Desenho de Prótese
3.
Laser Ther ; 22(1): 37-42, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24155548

RESUMO

BACKGROUND AND AIMS: Raman spectroscopy is a vibrational technique which provides information about the chemical structure. Nevertheless, since many chemicals are present in a cell at very low concentration, the Raman signal observed from a single cell is extremely weak. In surface enhanced Raman scattering (SERS), Raman signals can be enhanced by many orders of magnitude when nanoparticles are incorporated into the cell. Materials (subjects) and methods: The tumor biopsies were obtained from 5 patients who were clinically diagnosed with breast cancer. Breast cancer cells isolated from the biopsy were washed, centrifuged and seeded out. Cultivation took place in DMEM at 37°C in a humidified of 5% CO2 in air with addition of colloidal silver nanoparticles of 40 nm into the cell by sonication. Immediately, the washed cells were analyzed in phosphate buffered saline (PBS) at pH 7. Raman analysis was carried out on the Jobin-Yvon LabRAM HR800 microscope system, with a NIR 830 nm laser excitation source. RESULTS: The strongly enhanced Raman signals allow Raman measurements of a single cell in the 200-1800 cm(-1) range in relatively short collection times (5 second) using 17 mW near-infrared excitation. Observed spectral features differed across the cell, but chemical constituents in the cell nucleus and cytoplasm, such as DNA, RNA, and amino acids tyrosine and phenylalanine can be identified. CONCLUSIONS: Particularly strong field enhancement can be observed when nanoparticles form colloidal clusters. The results suggest that SERS could be a new technique for the identification of breast cancer cell.

4.
Acta Ortop Mex ; 27(1): 22-6, 2013.
Artigo em Espanhol | MEDLINE | ID: mdl-24701746

RESUMO

OBJECTIVE: To assess the clinical results and integrity of arthroscopic repair of rotator cuff tears using the suture bridge technique. MATERIAL AND METHODS: Fifty-six shoulders with total thickness rotator cuff tears were assessed. Mean follow-up was 19 months. Repair integrity was analyzed postoperatively with imaging and recovery times. RESULTS: The University of California at Los Angeles scale was used during the followup; the preoperative mean improved from 13.2 points to 29.7 (p\001). The rotator cuff healed completely in 66.7 of the 56 shoulders. The incidence of fatty regeneration of rotator cuff muscles was more common in individuals > 60 years of age (p = 0.002). The latter had a higher chance of recurrent tear (p\001). DISCUSSION: There was significant pain relief in the visual analogue scale and improvement in ranges of motion. The advantages of this technique include that it allows immobilizing with a sling without the need for maximum abduction protection; it is a safer repair due to the configuration of the double band intercrossed over the tendon that provides greater fixation and stability, with greater coverage of the tear defect.


Assuntos
Artroscopia/métodos , Manguito Rotador/cirurgia , Técnicas de Sutura , Adulto , Idoso , Artrometria Articular , Feminino , Seguimentos , Humanos , Imobilização , Masculino , Pessoa de Meia-Idade , Medição da Dor , Dor Pós-Operatória/etiologia , Dor Pós-Operatória/prevenção & controle , Estudos Retrospectivos , Índice de Gravidade de Doença , Síndrome de Colisão do Ombro/prevenção & controle , Resultado do Tratamento
5.
J Interferon Cytokine Res ; 16(12): 1079-88, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8974012

RESUMO

On the basis of their relative hydropathy and alpha-helical structure, we prepared antibodies to four synthetic peptides with amino acid sequences homolgous to four hydrophilic, extracellular regions of the murine 80 kDa type I interleukin-1 receptor (IL-1RI). Antibodies to each of the four peptides recognized their specific immunogen. Human [125I]-IL-1 alpha or -beta was crosslinked to murine EL4 and D10S cells. Antiserum to peptide 150-166 precipitated the IL-1/IL-1R complex, whereas antibodies to peptide 66-84, 190-200, or 266-285 did not. Antibody to peptide 150-166 did not precipitate the type II IL-1R. Anti-IL-1RI150-166 blocked 71% of the binding of radiolabeled human IL-1 beta to EL4 cells and 50% of the binding to D10S cells. Using affinity-purified anti-IL-1RI150-166, we compared the ability of this antibody to inhibit the binding of murine or human IL-1 alpha to that of murine or human IL-1 beta. At a concentration of 20 ng/ml, affinity-purified anti-IL-1RI150-166 blocked 50% binding of murine IL-1 beta. At 1 microgram/ml, 90% blockage was observed. In contrast, no significant blockade of IL-1 alpha binding was observed at concentrations as high as 3 micrograms/ml of anti-IL-1RI150-166. The selective blockade of IL-1 beta forms was not due to differences in the affinities of these ligands for receptors on these cells. The antibody also blocked the binding of human IL-1 beta but not human IL-1 alpha to EL4 cells. The biologic activity of murine IL-1 beta but not IL-1 alpha on EL4 cells was also inhibited by this antibody. These data suggest (1) that antibody to a specific epitope on the extracellular domain interferes with the binding of IL-1 beta but not IL-1 alpha, (2) the differential inhibition of binding of IL-1 beta but not IL-1 alpha by anti-IL-1RI150-166 also blocks biologic activity, and (3) IL-1 alpha and IL-1 beta may transduce different signals by binding to separate loci on the IL-1RI.


Assuntos
Reações Antígeno-Anticorpo , Interleucina-1/metabolismo , Fragmentos de Peptídeos/imunologia , Estrutura Secundária de Proteína , Receptores de Interleucina-1/imunologia , Sequência de Aminoácidos , Animais , Sítios de Ligação , Linhagem Celular , Humanos , Imunoglobulinas/química , Camundongos , Dados de Sequência Molecular , Peso Molecular , Testes de Precipitina , Receptores de Interleucina-1/química , Receptores de Interleucina-1/metabolismo , Solubilidade , Células Tumorais Cultivadas , Água/química
6.
Rev Alerg Mex ; 43(2): 29-33, 1996.
Artigo em Espanhol | MEDLINE | ID: mdl-8814887

RESUMO

Asthma results from a complex interaction between genetics and environmental factors. Authors have demonstrated the role play by these, however a greatest number of family and asthmatic patients not identify the sources of pollution into their home. A sampling of 369 patients finds that males were predominant mainly affecting before five years of age. 67.2% have factors of risk in their microenvironment (RR = 4.06; OR = 11.38; RA = 53.21; P = .001). Tobacco predominant with 129 patients (RR = 3.12; OR = 3.76; RA = 37.08; P = 0.04). Carpets in 32.29% (RR = 2.81; OR = 4.52; RA = 31.44; P = .007). Animals 19.24% (RR = 1.64; OR = 1.90; RA = 11.27; P = .051). Patients with a great number of broncoespasm acute description have been hospitalized rely on factors risk in their home. Data demonstrate the necessity to design projects of education to limit the family injury.


Assuntos
Alérgenos/efeitos adversos , Asma/etiologia , Exposição Ambiental , Habitação , Adolescente , Animais , Asma/epidemiologia , Gatos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Fatores de Risco
7.
Artigo em Inglês | MEDLINE | ID: mdl-8788584

RESUMO

The naphthoquinones 2-hydroxy-3-(1,1-dimethylallyl)-1,4-naphthoquinone (CS-1), (-)-2,3,3-trimethyl-2-3-dihydronaphtho[2,3-b]furan-4,9-quinone (CS-3), and 2-acetoxy-3-(1,1-dimethylallyl)-1,4-naphthoquinone (CS-5) isolated from Calceolaria sessilis were tested against Trypanosoma cruzi epimastigotes, the TA3 tumor cell line and the methotrexate-resistant subline TA3-MTX-R. Naphthoquinone CS-3 was the most active; the 50% culture growth inhibition (I50) on T. cruzi (Tulahuén and LQ strain and DM28c clone) was at concentrations ranging from 2.1 to 5.2 mumolar. Also CS-3 inhibited TA3 and TA3-MTX-R culture growth with an I50 of 2.1 and 3.8 mumolar, respectively. Naphthoquinone CS-3 inhibited the respiration of the tumor cells by interfering with the electron transport at some point between NADH and ubiquinone. The respiration of T. cruzi was not inhibited by naphthoquinone CS-3. Naphthoquinone CS-3 produced a temporary increase of oxygen consumption in T. cruzi and tumor cells, suggesting the generation and participation of free radicals.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Naftoquinonas/farmacologia , Plantas Medicinais/química , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Antineoplásicos Fitogênicos/isolamento & purificação , Respiração Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Masculino , Camundongos , Naftoquinonas/isolamento & purificação , Consumo de Oxigênio/efeitos dos fármacos , Explosão Respiratória/efeitos dos fármacos , Tripanossomicidas/isolamento & purificação , Trypanosoma cruzi/crescimento & desenvolvimento , Trypanosoma cruzi/metabolismo , Células Tumorais Cultivadas
8.
Biochem Pharmacol ; 48(10): 1935-42, 1994 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-7986205

RESUMO

The effects of nordihydroguaiaretic acid (NDGA), best known as an inhibitor of lipoxygenase activities, on the culture growth, oxygen consumption, ATP level, viability, and redox state of some electron carriers of intact TA3 and 786A ascites tumor cells have been studied. NDGA inhibited the respiration rate of these two tumor cell lines by preventing electron flow through the respiratory chain. Consequently, ATP levels, cell viability and culture growth rates were decreased. NDGA did not noticeably inhibit electron flow through both cytochrome oxidase and ubiquinone-cytochrome b-c1 complex. Also, the presence of NDGA changed to redox state of NAD(P)+ to a more reduced level, and the redox states of ubiquinone, cytochrome b and cytochromes c + c1 changed to a more oxidized level. These observations suggest that the electron transport in the tumor mitochondria was inhibited by NDGA at the NADH-dehydrogenase-ubiquinone level (energy-conserving site 1). As a consequence, mitochondrial ATP synthesis would be interrupted. This event could be related to the cytotoxic effect of NDGA.


Assuntos
Masoprocol/farmacologia , Consumo de Oxigênio/efeitos dos fármacos , Trifosfato de Adenosina/metabolismo , Animais , Transporte de Elétrons , Masculino , Camundongos , Mitocôndrias/metabolismo , Oxirredução , Células Tumorais Cultivadas
9.
Brain Res ; 612(1-2): 165-71, 1993 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-8330197

RESUMO

Several peptides (cytokines), viz., interleukin-1 (IL-1), interferon-alpha (IFN-alpha), interleukin-6 (IL-6), tumor necrosis factor (TNF), are formed in response to conditions causing tissue inflammation or damage and are implicated in reactive changes of the host, including fever, while IL-1 has been considered an important mediator of fever, the other cytokines, specifically IL-6 and TNF, have recently acquired prominence. The present study extends earlier research on IL-1 and addresses the question of the role of IL-6 and TNF in the genesis of fever. Experiments were conducted in the conscious cat, and IL-6 and TNF were assayed concomitantly in cerebrospinal fluid (CSF) from the third ventricle using specific bioassays. In the absence of fever, IL-6 was usually below the threshold of the assay (4-32 pg/ml), while TNF appeared measurable (424 +/- 57 pg/ml) in most experiments. A single intravenous injection of endotoxin (bolus) or continuous infusion of IL-1 at doses eliciting a sustained fever increased CSF levels of IL-6, but had no effect on concentrations of TNF. Intracerebroventricular injection of a pyrogenic dose of endotoxin led to an elevation of TNF and IL-6 and, in either case, the effect was manifest during the latent period before the fever. In addition, by the same route, IL-1 caused a rise in IL-6. We conclude that brain is intrinsically capable of producing both IL-6 and TNF depending on the site of challenge. However, since IL-6 CSF levels are elevated regardless of the site of pyrogen injection, IL-6 lends itself better to a role in the pathogenesis of fever.


Assuntos
Febre/líquido cefalorraquidiano , Interleucina-6/líquido cefalorraquidiano , Fator de Necrose Tumoral alfa/líquido cefalorraquidiano , Animais , Temperatura Corporal/efeitos dos fármacos , Química Encefálica/fisiologia , Gatos , Ventrículos Cerebrais/metabolismo , Escherichia coli , Feminino , Febre/induzido quimicamente , Injeções Intravenosas , Injeções Intraventriculares , Masculino , Polissacarídeos Bacterianos/farmacologia
10.
Infect Immun ; 61(3): 926-32, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8432613

RESUMO

Klebsiella pneumoniae, a worldwide cause of nosocomial infections, is one of the most common causes of death in newborns in nurseries. In this study, we investigated the role of interleukin-1 (IL-1) in an experimental animal model of neonatal sepsis, using a natural antagonist of IL-1 receptors, the IL-1 receptor antagonist (IL-1Ra), to block IL-1's effects in neonatal Klebsiella sepsis in the absence of antibiotic treatment. Newborn Wistar-Kyoto rats were injected intraperitoneally with a single dose (10 mg/kg) of either IL-1Ra (n = 43) or human serum albumin as a control (n = 40). At the same time, a 50% lethal dose of K. pneumoniae was injected subcutaneously. No antibiotics were given at any time. After 10 days, survival was 60% for the albumin group and 80% for the IL-1Ra group (P < 0.01). IL-1Ra treatment also afforded protection when the dose of bacteria was increased sixfold (P < 0.01). There were two episodes of leukopenia in the control group, which were suppressed by IL-1Ra (P < 0.01 and P < 0.001). IL-1 and IL-6 levels were lower in the IL-1Ra-treated group (P < 0.05 and P < 0.001, respectively). No differences between the two groups were observed in the number of bacteria in cultures of the blood, lungs, liver, or spleen. When IL-1Ra (10 mg/kg) was given both at time zero and 24 h after bacterial challenge, lethality was significantly increased (P < 0.01). Single doses of IL-1Ra of from 20 to 40 mg/kg progressively increased lethality compared with controls (P < 0.01) in both Wistar-Kyoto and Sprague-Dawley strain rats. In the same model, low doses of IL-1 itself (0.4 ng per rat), given 24 h prior to bacterial challenge, afforded protection (P < 0.001). These studies suggest that, in the absence of antibiotics, partial blockade of IL-1 receptors improves survival, whereas a longer or greater blockade increases lethality in newborn rats infected with K. pneumoniae.


Assuntos
Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/patogenicidade , Sialoglicoproteínas/administração & dosagem , Animais , Animais Recém-Nascidos , Atividade Bactericida do Sangue , Relação Dose-Resposta a Droga , Proteína Antagonista do Receptor de Interleucina 1 , Interleucina-1/metabolismo , Interleucina-6/metabolismo , Infecções por Klebsiella/imunologia , Ratos , Ratos Endogâmicos WKY , Ratos Sprague-Dawley , Receptores de Interleucina-1/efeitos dos fármacos
11.
Brain Res ; 562(2): 199-206, 1991 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-1773338

RESUMO

Fever induced by endogenous as well as exogenous pyrogens is often prevented by cyclooxygenase inhibitors; endogenous pyrogens stimulate prostaglandin E2 (PGE2) in or near the thermoregulatory centers of the brain. The cytokines, interleukin-1 (IL-1) and tumor necrosis factor (TNF), are two pyrogens which stimulate brain PGE2 formation during fever and also increase PGE2 synthesis in human mononuclear cells in vitro. In the present study, we examined whether interleukin-6 (IL-6) stimulates PGE2 formation in a manner similar to IL-1 and TNF. Both glycosylated and non-glycosylated forms of recombinant human IL-6 were tested. Following intravenous injection into rabbits, the glycosylated IL-6 was more pyrogenic than the non-glycosylated form and there was no evidence of synergy in the production of fever when IL-6 and IL-1 were given simultaneously. IL-6 fever was blocked by prior administration of the cyclooxygenase inhibitor ibuprofen. IL-6 was also pyrogenic in the cat by either the systemic or the intraventricular route. However, in both species, IL-6 was less effective than IL-1 beta. When given intraventricularly to cats, IL-6 produced an increase in PGE2 levels of the cerebrospinal fluid in parallel with the rise in body temperature. In the latter respect, IL-6 imitated IL-1 beta; however, IL-6 from 0.15-15 micrograms/ml did not increase mononuclear cell PGE2 production in vitro whereas IL-1 beta induced 20-30-fold increases in PGE2 at 100 ng/ml.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Encéfalo/metabolismo , Dinoprostona/biossíntese , Interleucina-6/fisiologia , Leucócitos Mononucleares/metabolismo , Pirogênios , Adulto , Animais , Bioensaio , Gatos , Dinoprostona/líquido cefalorraquidiano , Feminino , Humanos , Infusões Intravenosas , Interleucina-1/fisiologia , Ativação Linfocitária/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Coelhos , Linfócitos T/citologia
12.
J Biol Chem ; 266(22): 14147-50, 1991 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-1830582

RESUMO

The interleukin-1 receptor antagonist (IL-1ra) inhibits the binding of interleukin-1 (IL-1) to T-cell lines possessing the type I IL-1 receptor; evidence has been published (Carter, D. B., Deibel, M. R. J., Dunn, C. J., Tomich, C. S., Laborde, A. L., Slightom, J. L., Berger, A. E., Bienkowski, M. J., Sun, F. F., McEwan, R. N., Harris, P. K. W., Yem, A. W., Waszak, G. A., Chosay, J. G., Sieu, L. C., Hardee, M. M., Zurcher-Neely, H. A., Reardon, I. M., Heinrickson, R. L., Truesdell, S. E., Shelly, J. A., Eessalu, T. E., Taylor, B. M., and Tracey, D. E. (1990) Nature 344, 633-638; Hannum, C. H., Wilcox, C. J., Arend, W. P., Joslin, F. G., Dripps, D. J., Heimdal, P. L., Armes, L. G., Sommer, A., Eisenberg, S. P., and Thompson, R. C. (1990) Nature 343, 336-340) that IL-Ira does not bind to the type II IL-1 receptor (IL-1RtII). In this study we examined the ability of human recombinant IL-1ra to block the binding of IL-1 to the IL-1RtII on human polymorphonuclear leukocytes (PMN) and Raji human B-lymphoma cells. The binding of 125I-IL-1 beta to PMN was competively inhibited by IL-1ra. IL-1 beta was more potent in inhibiting the binding of 125I-IL-1 beta than IL-1ra. Incubating PMN with 125I-IL-1ra in the presence of increasing concentrations of IL-1 beta or IL-1ra showed that IL-1 beta was an approximately 40-fold more potent inhibitor of binding of 125I-IL-1ra than unlabeled IL-1ra. The IL-1ra was approximately 500-fold less potent in inhibiting the binding of 125I-IL-1 alpha than IL-1 alpha. IL-1ra was also able to competitively inhibit binding of 125I-IL-1 beta to Raji cells. PMN or Raji cells were also incubated with 125I-IL-1 in the absence or presence of IL-1 or IL-1ra. After cross-linking of IL-1 to cells followed by specific immunoprecipitation, sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed a band at 85 kDa corresponding to the 68-kDa IL-1RtII. However, in the presence of an excess of either unlabeled IL-1 or IL-1ra, the 85-kDa IL-1.IL-1RtII complex was not present. These findings demonstrate that the IL-1ra recognizes and blocks IL-1 binding to the IL-1RtII.


Assuntos
Interleucina-1/metabolismo , Receptores Imunológicos/antagonistas & inibidores , Ligação Competitiva , Reagentes de Ligações Cruzadas , Eletroforese em Gel de Poliacrilamida , Humanos , Interleucina-1/antagonistas & inibidores , Linfoma de Células B/metabolismo , Linfoma de Células B/patologia , Neutrófilos/metabolismo , Testes de Precipitina , Receptores Imunológicos/metabolismo , Receptores de Interleucina-1 , Proteínas Recombinantes/antagonistas & inibidores , Proteínas Recombinantes/metabolismo , Células Tumorais Cultivadas
13.
Bol Med Hosp Infant Mex ; 47(8): 589-92, 1990 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-2257098

RESUMO

This is a case study of a six year old boy with a previous history of a contuse trauma of the cervical spinal region who later developed fever, stiffening of the neck, and signs of spinal compression. A descending myelography detected a lesion at C4. The Nuclear Magnetic Resonance study of the area showed an anterior epidural mass extending from C5 to T1 which displaced the spinal cord. Surgery revealed an epidural abscess which was drained. The patient received parenteral antibiotic therapy.


Assuntos
Abscesso/diagnóstico , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Doenças da Medula Espinal/diagnóstico , Infecções Estafilocócicas/diagnóstico , Criança , Espaço Epidural , Humanos , Masculino
14.
Blood ; 75(1): 40-7, 1990 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-2294996

RESUMO

Interleukin-6 (IL-6) shares several biologic properties with IL-1, including hematopoietin-1 activity and stimulation of T cells. Because many of their biologic activities overlap, we developed and used a specific radioimmunoassay (RIA) for IL-6 to compare production of this cytokine on a molar basis with that of IL-1 alpha, IL-1 beta, and tumor necrosis factor (TNF)alpha. The RIA correlated well with the hybridoma bioassay for IL-6 (r = .87, P less than .001). Freshly isolated human peripheral blood mononuclear cells (PBMC) cultured in the absence of stimuli did not produce IL-6 in most cases. Kinetics of secretion and cell-association of IL-6 were studied. In contrast to IL-1 alpha but similar to TNF, IL-6 was almost entirely secreted into the extracellular fluid. Incubation with different stimuli (lipopolysaccharide [LPS], phytohemagglutinin [PHA], Staphylococcus epidermidis, or IL-1 alpha) resulted in production of IL-6. However, on a molar basis PBMC produced approximately two to three times less IL-6 than IL-1 alpha, IL-1 beta, or TNF, regardless of the stimulus. The amount of IL-6 produced from PBMC was consistent when measured in the same subjects six time during a 12-week period. In a cohort of 38 donors, the coefficient of variation for IL-6 production was .32, compared with .92 for IL-1 beta and .96 for TNF. Comparing cytokine production by PBMC, there was a significant correlation between IL-6 and IL-1 beta (r = .72) and between IL-6 and TNF (r = .66). IL-6 did not stimulate IL-1 beta or TNF production, but suppressed IL-1 beta and TNF production induced by LPS or PHA by 30% (P less than .01). This suppression of IL-1 beta and TNF by IL-6 appears to be on the level of transcription.


Assuntos
Interleucina-1/biossíntese , Interleucina-6/biossíntese , Leucócitos Mononucleares/metabolismo , Fator de Necrose Tumoral alfa/biossíntese , Bioensaio , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Técnicas In Vitro , Interleucina-1/genética , Interleucina-1/farmacologia , Interleucina-6/análise , RNA Mensageiro/genética , Radioimunoensaio , Fator de Necrose Tumoral alfa/genética
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