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1.
Adolesc Med ; 12(3): 379-88, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11602441

RESUMO

Most people would agree that it is preferable to grow up in a wealthy family than in one that is impoverished. However, adolescents who live in affluent families are in danger of developing a sense of entitlement that may impede future vocational and social success. Parental presence may be minimal, with discipline and child-rearing delegated to paid caretakers. The pressure to achieve in school may overwhelm the less than gifted adolescent. Excessive parental participation in school affairs may deter the adolescent from developing a sense of independence and competency. Eating disorders are more likely to develop in affluent youth. Participation in delinquent behaviors may be due to boredom with the affluent lifestyle, and such behavior may not be punished since youth from affluent families are often shielded from proper discipline by law enforcement authorities. Because of their social standing in the community and as a consequence of their wealth, affluent youth are in unique positions to become leaders and to participate in altruistic endeavors. Health care providers taking care of adolescents in wealthy families should be aware of these issues and should discuss them with adolescents and their families.


Assuntos
Comportamento do Adolescente , Psicologia do Adolescente , Classe Social , Adolescente , Humanos , Desenvolvimento da Personalidade , Relações Médico-Paciente
2.
Cancer ; 87(4): 184-9, 1999 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-10455205

RESUMO

BACKGROUND: The aim of this study was to quantify the prevalence of cervical smear abnormalities in sexually active adolescents and identify the effect of immune-modifying conditions. METHODS: Two hundred seventy-one females ages 13-22 years attending a clinic for sexually transmitted disease (STD) evaluation had cervical Papanicoloau (Pap) smears and completed sexual history questionnaires. Results of all follow-up Pap smears were obtained. Medical charts were available for 54 patients with cytologic follow-up and were reviewed for the presence of immune-modifying conditions. Follow-up smear results for patients with and without immune-modifying conditions were compared. Abnormality rates for all cervical smears seen in 1995 at Montefiore Medical Center were also obtained. RESULTS: The smear abnormality rate for adolescents was 20. 7% (abnormal squamous cells of undetermined significance [ASCUS], 12. 2%; low grade squamous intraepithelial lesion [LGSIL], 7.7%; high grade squamous intraepithelial lesion [HGSIL], 0.7%) compared with all adult females, for whom the rate was 13.2% (ASCUS, 9.9%; LGSIL, 2.5%; HGSIL, 0.6%; carcinoma 0.2%) (P < 0.0002). Of 20 initial ASCUS patients, 6 (30%) showed LGSIL or HGSIL on follow-up. Chart review allowed the clinical immune status of 54 patients to be determined. Of 14 patients with an immune-modifying condition (9 HIV positive patients, 3 receiving oral steroids, 1 liver transplant patient receiving steroids, and 1 with intestinal lymphangiectasia), 11 (78. 6%) developed or maintained an abnormality on cytologic follow-up. Of 40 patients with no identifiable immune-modifying condition, 11 (27.5%) developed or maintained an abnormality on cytologic follow-up (P < 0.00082). CONCLUSIONS: Sexually active adolescents are at higher risk of developing a significant cervical smear abnormality, especially LGSIL. Patients with an atypical Pap smear or immune-modifying condition require more attentive gynecologic monitoring. Cancer (Cancer Cytopathol)


Assuntos
Sistema Imunitário , Teste de Papanicolaou , Displasia do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/epidemiologia , Esfregaço Vaginal , Adolescente , Adulto , Progressão da Doença , Feminino , Seguimentos , Humanos , Cidade de Nova Iorque/epidemiologia , Prevalência , Fatores de Risco , Comportamento Sexual , Parceiros Sexuais , Neoplasias do Colo do Útero/patologia , Displasia do Colo do Útero/patologia
4.
J Adolesc Health ; 22(5): 389-93, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9589340

RESUMO

PURPOSE: This study was undertaken to determine if homelessness could serve as a marker for previous hepatitis B infection (HBI), and thus justify prevaccination screening. METHODS: One hundred sexually active 13-21-year-olds (mean = 17 years), 74% female, attending an inner-city hospital-based adolescent clinic (HOSP), and 48 sexually active 13-21-year-olds (mean = 19 years), 40% female, attending a clinic based at an urban drop-in center (UDC) for street youth were consecutively enrolled, screened for HBI serum markers and administered a structured interview about sexual practices, sexual abuse, prior sexually transmitted diseases (STDs), and injection drug use. RESULTS: For the HOSP group, 7% were homeless and 4% were HBI positive. In the UDC group, 96% were homeless and 23% were HBI positive. Homelessness was significantly associated with HBI (p < 0.001), and this was corroborated by logistic regression analysis (p < 0.01). Other factors significantly associated with HBI in adolescents included a history of anal sex (p < or = 0.002), anal-receptive sex (p < or = 0.01), genital Chlamydia (p < or = 0.03), prostitution (p < or = 0.03), and sexual abuse (p < or = 0.002). For both populations, gender, sexual orientation, intravenous drug use, and genital sex were not related to HBI. CONCLUSION: These data indicate that homelessness and associated high-risk sexual practices may be indications for prevaccination screening for HBI in adolescents.


Assuntos
Hepatite B/prevenção & controle , Jovens em Situação de Rua , Programas de Rastreamento , Assunção de Riscos , Adolescente , Adulto , Feminino , Vacinas contra Hepatite B , Humanos , Masculino , Fatores de Risco , Infecções Sexualmente Transmissíveis , População Urbana , Vacinação
6.
J Dev Behav Pediatr ; 16(5): 339-44, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8557834

RESUMO

This study examines the prevalence of problem behaviors (sexual activity, substance use, delinquency, and school failure) in a clinical hospital-based sample of 217 inner-city, 14 to 17 year olds with a variety of serious, chronic medical illnesses and compares this prevalence to that in a group of 121 similar-aged, healthy friends with no known chronic illnesses living in the same community. No differences were found between groups in substance use, delinquency, percent who had ever had sexual intercourse, or mean age at first intercourse. There was a significant interaction effect of chronic illness and gender on age at first intercourse (p = .015); boys without chronic illness initiated sexual intercourse at a younger age than their girlfriends without illness. Contrary to expectations, significantly more of the healthy friends had repeated a grade in school than had those with chronic illness (p = .002). Results are discussed in terms of the interrelationships of chronic illness, gender, and environment on problem behaviors.


Assuntos
Encenação , Doença Crônica/psicologia , Delinquência Juvenil/psicologia , Deficiências da Aprendizagem/psicologia , População Urbana , Adaptação Psicológica , Adolescente , Feminino , Humanos , Lactente , Deficiências da Aprendizagem/diagnóstico , Masculino , Cidade de Nova Iorque , Comportamento Sexual , Papel do Doente , Ajustamento Social , Meio Social
8.
Exp Hematol ; 22(7): 582-6, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8013574

RESUMO

Murine studies have reported elevated serum macrophage colony-stimulating factor (M-CSF) concentrations in animals inoculated with fungus; however, the human cytokine response to fungemia has not been described. Endogenous M-CSF serum concentrations were measured in 18 autologous bone marrow transplant patients with positive blood fungal cultures. Seventeen of the 18 patients received the same high-dose chemotherapy regimen with autologous hematopoietic support. M-CSF concentrations were determined in serum samples obtained 1 week before and within 2 days of the first positive blood culture. Serum M-CSF rose more than three-fold in a majority of patients at the time of positive culture in contrast to concentrations obtained in the previous week (medians 11.1 and 2.8 ng/mL, respectively; p = 0.001). Median values at the time of positive blood culture were also significantly higher than those obtained in a matched control group of patients without positive blood cultures (n = 18; median 2.60 ng/mL; p = 0.001). These data demonstrate that endogenous serum M-CSF is elevated in the early stages of human systemic fungal infection and thus may have important diagnostic and therapeutic implications.


Assuntos
Transplante de Medula Óssea/efeitos adversos , Fungemia/sangue , Fator Estimulador de Colônias de Macrófagos/sangue , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/terapia , Fatores Estimuladores de Colônias/uso terapêutico , Feminino , Humanos , Masculino , Melanoma/terapia , Pessoa de Meia-Idade
9.
J Immunol ; 152(5): 2421-9, 1994 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-8133053

RESUMO

IL-11 and IL-6 are fibroblast-derived cytokines with overlapping biologic properties. To determine whether IL-11 and IL-6 are similarly regulated, we characterized the effects of rIL-1 and TGF-beta (beta 1 and beta 2) on human lung fibroblast IL-11 production and compared this regulation with that of IL-6. Unstimulated fibroblasts did not produce significant amounts of IL-11, whereas rIL-1 alpha and TGF-beta were dose-dependent stimulators of IL-11 protein production, mRNA accumulation, and gene transcription. rIL-1 alpha and TGF-beta also interacted in a synergistic fashion to further increase IL-11 protein production and mRNA accumulation. The effects of rIL-1 and TGF-beta individually were not altered by the cyclic nucleotide-dependent protein kinase inhibitor HA1004, protein kinase C (PKC) inhibition with staurosporine, or chronic phorbol ester preincubation, or the calmodulin antagonists W7 and TFP. The effects of rIL-1 alpha and TGF-beta in combination were also unaltered by HA1004, staurosporine, and chronic phorbol ester exposure. A23187, however, did induce IL-11 mRNA accumulation and W7 and TFP did reverse the synergistic stimulation caused by rIL-1 and TGF-beta in combination. In contrast with the regulation of IL-11, TGF-beta did not effectively stimulate IL-6 mRNA accumulation, rIL-1 alpha was a more potent stimulator of IL-6 than IL-11 production, and rIL-1-induced IL-6 mRNA accumulation was augmented by W7 and TFP. These studies demonstrate that: 1) rIL-1, TGF-beta, and agents that increase intracellular calcium stimulate lung fibroblast IL-11; 2) the IL-11 stimulatory effects of rIL-1 and TGF-beta are, at least partially, transcriptionally mediated and are the result of signal transduction pathways that are largely PKC, cyclic nucleotide, and calmodulin independent; and 3) rIL-1 and TGF-beta interact in a synergistic fashion to further increase fibroblast IL-11 production and that this synergy is mediated by a largely PKC- and cyclic nucleotide-independent and calmodulin-dependent activation pathway. Importantly, they also demonstrate that rIL-1 and TGF-beta stimulate lung fibroblast IL-6 and IL-11 production via distinct and differentially regulatable activation pathways.


Assuntos
Fibroblastos/imunologia , Interleucina-11/metabolismo , Interleucina-1/farmacologia , Fator de Crescimento Transformador beta/farmacologia , Calcimicina/farmacologia , Linhagem Celular , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Interleucina-11/genética , Ouabaína/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes/farmacologia , Sistemas do Segundo Mensageiro , Transdução de Sinais , Acetato de Tetradecanoilforbol/farmacologia , Transcrição Gênica/efeitos dos fármacos
10.
Blood ; 81(11): 2925-35, 1993 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-8499631

RESUMO

Coagulation factor VIII (FVIII) is a cofactor in the intrinsic pathway of blood coagulation for which deficiency results in the bleeding disorder hemophilia A. FVIII contains a domain structure of A1-A2-B-A3-C1-C2 of which the B domain is dispensable for procoagulant activity in vitro. In this report, we compare the properties of B-domain-deleted FVIII (residues 760 through 1639, designated LA-VIII) to wildtype recombinant FVIII. In transfected Chinese hamster ovary (CHO) cells, LA-VIII was expressed at a 10- to 20-fold greater level compared with wildtype FVIII. The specific activity of purified LA-VIII was indistinguishable from wild-type recombinant FVIII and both exhibited similar thrombin activation coefficients. Wildtype recombinant-derived FVIII and LA-VIII also displayed similar timecourses of thrombin activation and heavy chain cleavage. However, compared with wildtype recombinant-derived FVIII, the light chain of LA-VIII was cleaved fivefold more rapidly by thrombin. Addition of purified von Willebrand factor (vWF) did not alter the kinetics of thrombin cleavage or activation of either wildtype recombinant-derived FVIII or LA-VIII. The immunogenicity of LA-VIII was compared with wildtype FVIII in a novel model of neonatal tolerance induction in mice. The results did not detect any immunologic differences between wildtype FVIII and LA-VIII, suggesting that LA-VIII does not contain significant new epitopes that are absent in wildtype FVIII. LA-VIII was tolerated well on infusion into FVIII-deficient dogs and was able to correct the cuticle bleeding time similar to wildtype recombinant factor VIII. In vivo, LA-VIII was bound to canine vWF and exhibited a half-life similar to wildtype recombinant FVIII. These studies support that B-domain-deleted FVIII may be efficacious in treatment of hemophilia A in humans.


Assuntos
Fator VIII/química , Animais , Células CHO , Cricetinae , Cães , Fator VIII/imunologia , Fator VIII/metabolismo , Expressão Gênica , Glicoproteínas/metabolismo , Humanos , Tolerância Imunológica , Peso Molecular , Processamento de Proteína Pós-Traducional , RNA Mensageiro/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/imunologia , Relação Estrutura-Atividade , Fator de von Willebrand/metabolismo
11.
J Clin Invest ; 90(5): 1879-88, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1385477

RESUMO

IL-3 is a glycoprotein cytokine involved in the hematopoietic response to infectious, immunologic, and inflammatory stimuli. In addition, clinical administration of recombinant IL-3 augments recovery in states of natural and treatment-related marrow failure. IL-3 acts by binding to high affinity cell surface receptors present on hematopoietic cells. To determine the site(s) at which IL-3 binds to it receptor, we analyzed a series of interspecies chimera of the growth factor for species-specific receptor binding and biological activity. The results suggest that IL-3 binds to its receptor and triggers a proliferative stimulus through two noncontiguous helical domains located near the amino terminus and the carboxy terminus of the molecule. To corroborate these findings, we have also mapped the binding epitopes of 10 mAb of human or murine IL-3, and have defined four distinct epitopes. Two of these epitopes comprise the amino-terminal receptor binding domain. A third epitope corresponds to the carboxy-terminal receptor interactive domain, and the fourth epitope, apparently not involved in the interaction of IL-3 and its receptor, lies between these sites. And on the basis of sandwich immunoassays using pairs of these mAbs, the two receptor interactive regions appear to reside in close juxtaposition in the tertiary structure of the molecule. These results provide a correlation of the structure-function relationships of IL-3 that should prove useful in evaluating the details of IL-3-IL-3 receptor interaction and in the rational design of clinically useful derivatives of this growth factor.


Assuntos
Interleucina-3/farmacologia , Proteínas Recombinantes de Fusão/farmacologia , Adulto , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/imunologia , Reações Cruzadas , Epitopos/análise , Humanos , Hylobates , Interleucina-3/química , Interleucina-3/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Ratos , Ratos Endogâmicos Lew , Receptores de Interleucina-3/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Relação Estrutura-Atividade
12.
Pediatr Rev ; 13(8): 314-8, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1437897

RESUMO

Abuse of drugs and alcohol is pervasive in our society. The role of the pediatrician as a health-care provider from birth through young adulthood includes recognizing the stigmata in newborns of prenatally ingested drugs as well as being able to treat neonatal drug withdrawal syndromes. Questioning about drug use and other closely related topics should be incorporated into all health-care maintenance visits, starting at the age of 10 y, with parental participation and anticipatory guidance being offered. Physical examination and laboratory testing are not as helpful in confirming an impression of substance abuse as a comprehensive interview and a full appreciation of the warning signs of substance abuse. Treatment of the problematic user with a multidisciplinary team that understands adolescent development and behavior as well as the problem of substance abuse is crucial. The decision to treat the teen in an ambulatory or inpatient setting is determined by the extent of abuse, underlying medical problems and psychopathology, and the degree of family dysfunction. The pediatrician must not avoid addressing these issues with patients. If, however, upon identifying an adolescent or a newborn with a drug problem, the pediatrician feels uncomfortable or ill-prepared to manage the patient, appropriate professional referrals are warranted. Despite exercising the referral option for treatment, as advocate for child and family, the pediatrician remains professionally bound to track all drug abuse-related referrals while continuing to participate in the general ongoing care of the patient and family. Finally, the pediatrician should retain a public advocacy role in the community by offering educational, preventive, and supportive efforts in the continuing struggle against drug abuse.


Assuntos
Comportamento do Adolescente , Efeitos Tardios da Exposição Pré-Natal , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Transtornos Relacionados ao Uso de Substâncias/terapia , Adolescente , Feminino , Humanos , Recém-Nascido , Entrevistas como Assunto , Pediatria , Exame Físico , Gravidez
13.
Proc Natl Acad Sci U S A ; 88(18): 8006-10, 1991 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-1654552

RESUMO

The encephalomyocarditis virus (EMCV) leader sequence is responsible for efficient, cap-independent translation initiation from the viral RNA. It has been used to increase the expression of internal coding regions on polycistronic mRNA encoded by recombinant DNA constructs. We have designed a sequence-replacement-type vector for targeting to immunoglobulin heavy-chain loci in hybridoma cells. Homologous recombination of this vector introduces a human gamma 1 constant-region sequence linked to the EMCV leader and a neomycin phosphotransferase (neo) gene. The resulting cells express a bicistronic mRNA encoding at the 5' end a chimeric murine VDJH-human C gamma 1 heavy chain, followed by neo linked to the internal ribosome binding site provided by the EMCV leader. These homologous recombinants express the chimeric heavy chain at levels equivalent to the heavy chain in the parental hybridoma. This strategy of using an EMCV-neo cassette to obtain efficient selectable marker gene expression has potential application to a range of gene targeting vectors.


Assuntos
Vírus da Encefalomiocardite/genética , Rearranjo Gênico de Cadeia Pesada de Linfócito B , Genes de Imunoglobulinas , Cadeias Pesadas de Imunoglobulinas/genética , Recombinação Genética , Ribossomos/metabolismo , Animais , Sequência de Bases , Expressão Gênica , Genes de Troca , Vetores Genéticos , Hibridomas , Camundongos , Dados de Sequência Molecular , Oligonucleotídeos/química , Biossíntese de Proteínas , RNA Mensageiro/genética , Proteínas Recombinantes de Fusão
14.
J Immunol ; 145(9): 3011-6, 1990 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-2120343

RESUMO

The expression of lambda L and microH chain cDNA was examined in Chinese hamster ovary cells. Each cDNA was linked to a different, amplifiable, selectable drug marker gene, and expression was monitored in the presence of increasing concentrations of the selective drugs. Cells were obtained that produced greater than 60 micrograms/10(6) cells/48 h of assembled antibody. This Chinese hamster ovary cell-synthesized IgM was polymeric, and exhibited specific hapten binding and C fixation. The expression strategy employed here may prove useful for the future production of genetically engineered antibodies and other multi-subunit proteins.


Assuntos
Anticorpos/genética , Proteínas de Choque Térmico , Imunoglobulinas/genética , Chaperonas Moleculares , Animais , Especificidade de Anticorpos , Sequência de Bases , Proteínas de Transporte/metabolismo , Linhagem Celular , Clonagem Molecular/métodos , Testes de Fixação de Complemento , Cricetinae , Cricetulus , DNA/genética , Chaperona BiP do Retículo Endoplasmático , Engenharia Genética/métodos , Cadeias lambda de Imunoglobulina/genética , Cadeias mu de Imunoglobulina/genética , Dados de Sequência Molecular , Nitrofenóis/imunologia , Fenilacetatos , Proteínas Recombinantes , Transfecção
15.
Blood ; 75(4): 874-80, 1990 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-2154268

RESUMO

We have generated four high affinity monoclonal antibodies (MoAbs) to recombinant human erythropoietin (EPO). All four MoAbs immunoprecipitate radioiodinated native EPO, and the concentrations of MoAbs required for maximum binding range from 10 nmol/L to 100 nmol/L. Two MoAbs, designated Group I MoAbs, bind to an epitope within the N-terminal 20 amino acids of EPO and also immunoprecipitate sodium dodecyl sulfate (SDS)-denatured EPO. Two other MoAbs (Group II MoAbs) do not immunoprecipitate SDS-denatured EPO and do not bind to any of the eight endo C fragments of EPO. We first used murine erythroleukemia (MEL) cells to test the MoAbs for inhibition of EPO-receptor binding. MEL cells, although unresponsive to EPO, express 760 high affinity receptors for EPO per cell (Kd = 0.24 nmol/L). To assay our MoAbs, MEL cells were grown as monolayers on fibronectin-coated Petri dishes and incubated at 4 degrees C with radioiodinated EPO. Group I MoAbs do not inhibit binding of radioiodinated EPO to the MEL EPO-receptor, but Group II MoAbs do inhibit binding in a dose-dependent manner. We next examined the neutralization of EPO bioactivity by our MoAbs, using EPO-dependent cell line. Only Group II MoAbs inhibit a newly developed EPO-dependent cell growth, demonstrating that inhibition of EPO-receptor binding correlates with neutralization of EPO bioactivity.


Assuntos
Anticorpos Monoclonais/imunologia , Eritropoetina/metabolismo , Receptores de Superfície Celular/metabolismo , Animais , Anticorpos Monoclonais/isolamento & purificação , Linhagem Celular , Membrana Celular/ultraestrutura , Eritropoetina/imunologia , Leucemia Eritroblástica Aguda/sangue , Leucemia Eritroblástica Aguda/patologia , Camundongos , Camundongos Endogâmicos BALB C , Testes de Neutralização , Testes de Precipitina , Receptores de Superfície Celular/antagonistas & inibidores , Receptores da Eritropoetina
16.
Experientia ; 42(10): 1159-62, 1986 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-3533608

RESUMO

Six of a total of 14 human colon carcinoma cell lines produce and secrete lysozyme in vitro. Three also produce the enzyme when propagated in vivo in athymic mice. None of the lysozyme positive cells stained in a manner typical of Paneth cells. Additionally, lysozymes from all six colon lines possess identical molecular weights (approximately 14,000 daltons).


Assuntos
Neoplasias do Colo/enzimologia , Muramidase/metabolismo , Animais , Linhagem Celular , Histocitoquímica , Humanos , Técnicas Imunoenzimáticas , Camundongos , Camundongos Endogâmicos BALB C , Transplante de Neoplasias
17.
Biochemistry ; 24(27): 7866-71, 1985 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-2418873

RESUMO

Plasma membranes from the human colon adenocarcinoma cell line HT-29 have been isolated and examined for the presence of angiogenic activity. Membrane-associated macromolecules extracted with Triton X-100 were fractionated on immobilized wheat germ agglutinin. The fraction which bound specifically (about 200 ng of protein/mL packed cells) was highly angiogenic when assayed on the chick embryo chorioallantoic membrane. As little as 0.2 ng of this human tumor derived material consistently induced neovascularization. Similarly, 1-2 ng of this material implanted into the rabbit cornea induced new vessel growth (5-8 mm) within 10 days. The plasma membranes of eight other human tumor lines were examined for angiogenic activity. For each, the wheat germ agglutinin bound material induced neovascularization at the low nanogram level. In contrast, the wheat germ agglutinin bound material derived from purified plasma membranes of two normal human diploid fibroblast cell lines failed to induce an angiogenic response on the chick chorioallantoic membrane, even at microgram levels.


Assuntos
Membrana Celular/fisiologia , Neoplasias/fisiopatologia , Neovascularização Patológica , Animais , Fracionamento Celular , Linhagem Celular , Membrana Celular/ultraestrutura , Córnea/irrigação sanguínea , Humanos , Coelhos
18.
Int J Cancer ; 36(4): 473-8, 1985 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-4044056

RESUMO

The established human colon adenocarcinoma cell line, HT-29, secretes a vascular permeability factor (VPF) in vitro. The factor has been purified from serum-free conditioned medium by acidification, cation-exchange, and reverse-phase and anion-exchange high-performance liquid chromatography. The VPF is a non-glycosylated acidic protein of apparent molecular weight 45,000, and is at least 4 orders of magnitude more potent than histamine as an inducer of vascular permeability. Its biological activity is unaffected by soybean trypsin inhibitor or by inhibitors of histamine, kinins, prostaglandins, or acid proteases. The VPF induces vascular permeability within minutes, which suggests a direct effect on the endothelial cell.


Assuntos
Adenocarcinoma/metabolismo , Permeabilidade Capilar , Neoplasias do Colo/metabolismo , Linfocinas/isolamento & purificação , Linhagem Celular , Cromatografia de Afinidade , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Eletroforese em Gel de Poliacrilamida , Humanos , Linfocinas/metabolismo , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
19.
Biochemistry ; 24(19): 4969-73, 1985 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-2416338

RESUMO

The angiogenic capacity of the class 1 heparin-binding growth factor from bovine brain, an anionic endothelial cell mitogen of Mr 16 000, has been evaluated. Its ability to induce the growth of new blood vessels has been assessed by means of two established assay systems. On the embryonic chick chorioallantoic membrane dose-response studies demonstrate that 160 ng (10 pmol) of mitogen is required to induce angiogenesis in greater than 50% of the eggs within 72 h. In the presence of 1 unit of exogenous heparin only 40 ng of mitogen (2.5 pmol) is needed to induce a similar response. Moreover, this occurs within 48 h, indicating that heparin also augments the angiogenic response by enhancing the rate of induction of angiogenesis. Eighty nanograms (5 pmol) of mitogen also induces the ingrowth of new blood vessels into the rabbit cornea, both in the presence and in the absence of heparin. These results establish that the class 1 heparin-binding growth factor from bovine brain is an angiogenesis factor. Importantly, the neovascularization induced by this angiogenesis factor is enhanced by heparin. The mechanistic implications for neovascularization under certain normal and pathological conditions are discussed.


Assuntos
Encéfalo/fisiologia , Circulação Cerebrovascular , Substâncias de Crescimento/fisiologia , Heparina/fisiologia , Neovascularização Patológica , Animais , Encéfalo/efeitos dos fármacos , Bovinos , Córnea/irrigação sanguínea , Córnea/efeitos dos fármacos , Transplante de Córnea , Fator 1 de Crescimento de Fibroblastos , Substâncias de Crescimento/isolamento & purificação , Substâncias de Crescimento/farmacologia , Heparina/isolamento & purificação , Heparina/farmacologia , Cinética , Coelhos
20.
Biochemistry ; 24(20): 5486-94, 1985 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-2866794

RESUMO

The amino acid sequence and disulfide bond pairing of human tumor derived angiogenin, the first tumor angiogenesis factor to be isolated in pure form from human sources, have been determined by conventional sequencing techniques adapted and applied to nanomole and subnanomole levels of material. Angiogenin, obtained from conditioned media of a human colonic adenocarcinoma cell line, is a single-chain protein consisting of 123 amino acids with the following sequences: less than Glu1-Asp-Asn-Ser-Arg-Tyr-Thr-His- Phe-Leu-Thr-Gln-His-Tyr-Asp15-Ala-Lys-Pro-Gln-Gly-Arg-Asp-Asp- Arg-Tyr-Cys-Glu-Ser-Ile-Met30- Arg-Arg-Arg-Gly-Leu-Thr-Ser-Pro-Cys-Lys-Asp-Ile-Asn-Thr- Phe45-Ile-His-Gly-Asn-Lys-Arg-Ser -Ile-Lys-Ala-Ile-Cys-Glu-Asn-Lys60-Asn-Gly-Asn-Pro-His-Arg-Glu-Asn -Leu-Arg-Ile -Ser-Lys-Ser-Ser75 -Phe-Gln-Val-Thr-Thr-Cys-Lys-Leu-His-Gly-Gly-Ser-Pro-Trp-Pro90-Pro -Cys-Gln-Tyr -Arg-Ala-Thr-Ala -Gly-Phe-Arg-Asn-Val-Val-Val105-Ala-Cys-Glu-Asn-Gly-Leu-Pro-Val- His-Leu-Asp-Gln-Ser-Ile-Phe120-Arg-Arg-Pro123-OH. Three disulfide bonds link the half-cystinyl residues 26-81, 39-92, and 57-107. The sequence is homologous to that of the pancreatic ribonucleases with 35% identity and many of the remaining residues conservatively replaced. Similarities are especially apparent around the major active-site residues His-12, Lys-41, and His-119 of ribonuclease which are conserved as are three of the four disulfide bonds.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Adenocarcinoma/análise , Indutores da Angiogênese/isolamento & purificação , Neoplasias do Colo/análise , Substâncias de Crescimento/isolamento & purificação , Proteínas de Neoplasias/isolamento & purificação , Ribonuclease Pancreático , Sequência de Aminoácidos , Animais , Linhagem Celular , Brometo de Cianogênio , Cavalos , Humanos , Hidroxilamina , Hidroxilaminas , Indicadores e Reagentes , Fragmentos de Peptídeos/análise , Piroglutamil-Peptidase I , Especificidade da Espécie , Tripsina
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