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1.
Soc Psychiatry Psychiatr Epidemiol ; 58(10): 1447-1456, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36808500

RESUMO

BACKGROUND: Substance use remains a barrier to recovery for young people accessing early intervention services for psychosis. While correlates of use have been explored in populations experiencing a first episode of psychosis (FEP), sample sizes have been small and less research assesses cohorts at ultrahigh risk of psychosis (UHR). METHODS: This study uses data from a naturalistic cohort including UHR and FEP participants (N = 1252) to elucidate clinical correlates of use in the past 3 months of any illicit substance, amphetamine-type stimulants (ATS), cannabis, and tobacco. Moreover, network analysis based on use of these substances and additionally alcohol, cocaine, hallucinogens, sedatives, inhalants, and opioids was completed. RESULTS: Young people with FEP used substances at significantly higher rates than those at UHR. High concurrence of use was seen between substances. In the FEP group, participants who had used any illicit substance, ATS, and/or tobacco had increased positive symptoms and decreased negative symptoms. Young people with FEP who used cannabis had increased positive symptoms. In the UHR group, participants who had used any illicit substance, ATS, and/or cannabis in the past 3 months showed decreased negative symptoms compared to those who had not. CONCLUSION: A distinct clinical picture of more florid positive symptoms and alleviated negative symptoms seen in those who use substances in the FEP group appears muted in the UHR cohort. Treating young people at UHR in early intervention services represents the earliest opportunity to address substance use early to improve outcomes.


Assuntos
Transtornos Psicóticos , Transtornos Relacionados ao Uso de Substâncias , Humanos , Adolescente , Transtornos Psicóticos/terapia , Transtornos Relacionados ao Uso de Substâncias/epidemiologia
2.
Nat Cell Biol ; 3(4): 409-16, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11283615

RESUMO

TRAIL (tumour-necrosis factor-related apoptosis ligand or Apo2L) triggers apoptosis through engagement of the death receptors TRAIL-R1 (also known as DR4) and TRAIL-R2 (DR5). Here we show that the c-Rel subunit of the transcription factor NF-kappaB induces expression of TRAIL-R1 and TRAIL-R2; conversely, a transdominant mutant of the inhibitory protein IkappaBalpha or a transactivation-deficient mutant of c-Rel reduces expression of either death receptor. Whereas NF-kappaB promotes death receptor expression, cytokine-mediated activation of the RelA subunit of NF-kappaB also increases expression of the apoptosis inhibitor, Bcl-xL, and protects cells from TRAIL. Inhibition of NF-kappaB by blocking activation of the IkappaB kinase complex reduces Bcl-x L expression and sensitizes tumour cells to TRAIL-induced apoptosis. The ability to induce death receptors or Bcl-xL may explain the dual roles of NF-kappaB as a mediator or inhibitor of cell death during immune and stress responses.


Assuntos
Regulação da Expressão Gênica , Proteínas I-kappa B , Glicoproteínas de Membrana/metabolismo , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-rel/metabolismo , Receptores do Fator de Necrose Tumoral/genética , Fator de Necrose Tumoral alfa/metabolismo , Animais , Apoptose , Proteínas Reguladoras de Apoptose , Proteínas de Ligação a DNA/metabolismo , Células HeLa , Humanos , Glicoproteínas de Membrana/farmacologia , Camundongos , Inibidor de NF-kappaB alfa , NF-kappa B/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-rel/genética , Tolerância a Radiação , Receptores do Ligante Indutor de Apoptose Relacionado a TNF , Receptores do Fator de Necrose Tumoral/biossíntese , Ligante Indutor de Apoptose Relacionado a TNF , Fator de Transcrição RelA , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/farmacologia , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteína bcl-X
3.
Nat Med ; 1(1): 65-8, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7584955

RESUMO

AIDS is associated with a high risk of certain malignancies, notably Kaposi's sarcoma (KS) and B-cell non-Hodgkin's lymphoma (NHL). The pathogenesis of these malignancies is not fully understood. One mechanism of malignant transformation recently described in colon tumorigenesis results from defects in DNA mismatch repair, manifest as widespread microsatellite instability. We demonstrate a high rate of microsatellite instability in KS and aggressive lymphomas obtained from HIV-infected patients, whereas there is no evidence of instability in similar lesions from HIV-negative patients. Further elucidation of the underlying mechanisms responsible for HIV-associated instability in primary tumours may provide insight into the pathogenesis of these AIDS-related neoplasms.


Assuntos
DNA de Neoplasias/genética , Infecções por HIV/genética , Linfoma não Hodgkin/genética , Repetições de Microssatélites , Sarcoma de Kaposi/genética , Reparo do DNA , DNA Viral/análise , Marcadores Genéticos , Humanos
4.
Nat Med ; 2(10): 1140-3, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8837615

RESUMO

The induction of tumor cell death by anticancer therapy results from a genetic program of autonomous cell death termed apoptosis. Because the p53 tumor suppressor gene is a critical component for induction of apoptosis in response to DNA damage, its inactivation in cancers may be responsible for their resistance to genotoxic anticancer agents. The cellular response to DNA damage involves a cell-cycle arrest at both the G1/S and G2/M transitions; these checkpoints maintain viability by preventing the replication or segregation of damaged DNA. The arrest at the G1 checkpoint is mediated by p53-dependent induction of p21WAF1/CIP1, whereas the G2 arrest involves inactivation of p34cdc2 kinase. Following DNA damage, p53-deficient cells fail to arrest at G1 and accumulate at the G2/M transition. We demonstrate that abrogation of G2 arrest by caffeine-mediated activation of p34cdc2 kinase results in the selective sensitization of p53-deficient primary and tumor cells to irradiation-induced apoptosis. These data suggest that pharmacologic activation of p34cdc2 kinase may be a useful therapeutic strategy for circumventing the resistance of p53-deficient cancers to genotoxic anticancer agents.


Assuntos
Apoptose/efeitos dos fármacos , Medula Óssea/efeitos dos fármacos , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Proteína Quinase CDC2/metabolismo , Cafeína/farmacologia , Tolerância a Radiação/efeitos dos fármacos , Proteína Supressora de Tumor p53/deficiência , Animais , Apoptose/efeitos da radiação , Medula Óssea/efeitos da radiação , Linfócitos T CD4-Positivos/efeitos da radiação , Linfócitos T CD8-Positivos/efeitos da radiação , Dano ao DNA , Ativação Enzimática/efeitos dos fármacos , Feminino , Fase G2/efeitos dos fármacos , Genes p53 , Masculino , Camundongos , Camundongos Knockout , Proteína Supressora de Tumor p53/fisiologia
5.
Ir J Psychol Med ; 38(1): 30-39, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32317033

RESUMO

INTRODUCTION: Tobacco smoking is a leading cause of preventable death and disease worldwide. Adults with mental ill-health smoke tobacco at substantially higher rates than other adults, with public health approaches effective in the population overall having less impact on those with mental ill-health. However, less is known about the tobacco smoking behaviours, attitudes and knowledge of young people with mental ill-health, despite this being the peak period of onset for both mental illness and cigarette smoking. METHODS: Young people attending a youth mental health centre (providing both primary and specialist care) in Melbourne, Australia were approached by youth peer researchers and asked to complete a survey about smoking behaviours, attitudes and knowledge. We examined smoking and associated attitudes in the sample overall, and as a function of the services accessed. RESULTS: In total, 114 young people completed the survey, with 56.3% reporting lifetime cigarette smoking, 42.0% smoking in the last 12 months and 28.6% in the past week. Of current regular smokers, 75.0% acknowledged they should quit in the future; however, only 23.5% planned to do so in the next month, with 44.4% confident that they could quit. Participants lacked knowledge about interactions between tobacco smoking, mental and physical health. CONCLUSIONS: Youth presenting for mental ill-health had high rates of cigarette smoking relative to population rates. Presentation at youth mental health services may represent a critical window for early intervention to reduce the lifetime impacts of cigarette smoking in mental ill-health. Interventions to support smoking cessation in this group are urgently needed.


Assuntos
Saúde Mental , Abandono do Hábito de Fumar , Adolescente , Adulto , Atitude , Austrália , Humanos , Fumar Tabaco
6.
Science ; 271(5245): 81-4, 1996 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-8539604

RESUMO

A speech processing algorithm was developed to create more salient versions of the rapidly changing elements in the acoustic waveform of speech that have been shown to be deficiently processed by language-learning impaired (LLI) children. LLI children received extensive daily training, over a 4-week period, with listening exercises in which all speech was translated into this synthetic form. They also received daily training with computer "games" designed to adaptively drive improvements in temporal processing thresholds. Significant improvements in speech discrimination and language comprehension abilities were demonstrated in two independent groups of LLI children.


Assuntos
Transtornos da Linguagem/terapia , Terapia da Linguagem , Deficiências da Aprendizagem/terapia , Software , Jogos de Vídeo , Algoritmos , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Percepção da Fala
7.
J Psychopharmacol ; 22(8): 872-81, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18208933

RESUMO

Previous research has found relationships between self-rated memory and ecstasy use, such that heavier users report worse function. These findings have been interpreted in terms of objective memory capacity. However, research on metamemory suggests that self-reported memory may be only weakly related to objective function, with demographics, mood, and memory-related beliefs and feelings also contributing to ratings. This study examined relationships between ecstasy/other drug use and self-reported memory, controlling for effects of demographic factors and mood. Associations between self-reported memory, memory-related beliefs and feelings, and objectively-measured cognitive function were also examined. Forty-five ecstasy polydrug, 48 cannabis polydrug, and 40 legal drug users completed a battery of neuropsychological tests and questionnaire measures of metamemory, including memory-related control beliefs, memory-related anxiety, and self-reported prospective and general/retrospective memory. The combined polydrug groups reported more general/retrospective memory failures. Covariance analysis, however, suggested that this finding was confounded by general anxiety levels. A combination of objective cognitive measures contributed to prediction of self-rated prospective memory, with demographics, mood, and memory-related anxiety also contributing to variability. However, associations between objective and self-reported memory were not strong. Self-report may not be a specific methodology with which to assess objective memory capacities in ecstasy and other drug users.


Assuntos
Transtornos da Memória/induzido quimicamente , N-Metil-3,4-Metilenodioxianfetamina/toxicidade , Transtornos Relacionados ao Uso de Substâncias/psicologia , Adolescente , Adulto , Cognição/efeitos dos fármacos , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Masculino
8.
Caries Res ; 42(6): 435-43, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18832830

RESUMO

Previous studies have shown that sucrose promotes changes in the composition of the extracellular matrix (ECM) of plaque-like biofilm (PLB), but its effect on protein expression has not been studied in vivo. Therefore, the protein compositions of ECM of PLB formed with and without sucrose exposure were analyzed by two-dimensional gel electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). For this purpose, a crossover study was conducted during two phases of 14 days each, during which a volunteer wore a palatal appliance containing eight enamel blocks for PLB accumulation. In each phase, a 20% sucrose solution or distilled and deionized water (control) were extraorally dripped onto the blocks 8x/day. On the 14th day, the PLB were collected, the ECM proteins were extracted, separated by two-dimensional gel electrophoresis, digested by in-gel trypsin and MALDI-TOF MS analyzed. In the ECM of PLB formed under sucrose exposure, the following changes compared with the control PLB were observed: (1) the presence of upregulated proteins that may be involved in bacterial response to environmental changes induced by sucrose and (2) the absence of calcium-binding proteins that may partly explain the low inorganic concentration found in ECM of PLB formed under sucrose exposure. The findings showing that sucrose affected the ECM protein composition of PLB in vivo provide further insight into the unique cariogenic properties of this dietary carbohydrate.


Assuntos
Biofilmes/efeitos dos fármacos , Cariogênicos/farmacologia , Placa Dentária/microbiologia , Matriz Extracelular/efeitos dos fármacos , Proteoma/análise , Sacarose/farmacologia , Adulto , Proteínas de Bactérias/análise , Proteínas de Ligação ao Cálcio/análise , Estudos Cross-Over , Esmalte Dentário/microbiologia , Placa Dentária/química , Eletroforese em Gel Bidimensional , Matriz Extracelular/química , Humanos , Concentração de Íons de Hidrogênio , Isoformas de Proteínas/análise , Proteoma/efeitos dos fármacos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
9.
Indian J Clin Biochem ; 23(1): 33-7, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23105716

RESUMO

Coronary Artery Disease is the major cause of mortality and morbidity worldwide. Traditional risk factors account for only half of the morbidity and mortality from coronary artery disease. There is substantial evidence that oxidative stress plays the major role in the atherosclerotic process. The present study was undertaken to evaluate the level of lipid peroxidation (by measuring malondialdehyde) and antioxidant enzymes (ceruloplasmin, glutathione, superoxide dismutase) in coronary artery disease. Serum malondialdehyde levels and serum ceruloplasmin levels were significantly raised in all the subgroups of study group as compared to control group (p<0.001). Whole blood glutathione levels and hemolysate superoxide dismutase activity was significantly decreased in all the subgroups of study group as compared to control group (p<0.001). Above results suggests that the patients of coronary artery disease show increased oxidative stress and decreased levels of antioxidant enzymes. So it is recommended that the management protocol for coronary artery disease patients should include antioxidant supplementation along with simultaneous lowering of lipid peroxidation.

10.
Malays Orthop J ; 11(1): 71-73, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28435580

RESUMO

Dislocation of multiple metatarsophalangeal joint is an uncommon injury. The mechanism of injury is a high energy force distal to proximal with foot in hyperextension at the metatarsophalangeal (MTP) joint. The acute hyperextension of the toe at the moment of injury causes avulsion of the plantar part of the capsule from the junction of head and neck of the metatarsal. If the collateral ligaments remain intact, they maintain the locked fibrocartilaginous plate over the dorsum of the head of the metatarsal, making closed reduction impossible. We report a case of simultaneous 1st and 2nd MTP joint open dislocation. In the present case, we chose the plantar approach utilizing the already present plantar wound. At 18 months post-operative follow-up, there was no instance of redislocations or signs of avascular necrosis of head of metatarsal.

11.
J Dent Res ; 85(10): 878-87, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16998125

RESUMO

Dental caries is a biofilm-dependent oral disease, and fermentable dietary carbohydrates are the key environmental factors involved in its initiation and development. However, among the carbohydrates, sucrose is considered the most cariogenic, because, in addition to being fermented by oral bacteria, it is a substrate for the synthesis of extracellular (EPS) and intracellular (IPS) polysaccharides. Therefore, while the low pH environment triggers the shift of the resident plaque microflora to a more cariogenic one, EPS promote changes in the composition of the biofilms' matrix. Furthermore, it has recently been shown that the biofilm formed in the presence of sucrose presents low concentrations of Ca, P(i), and F, which are critical ions involved in de- and remineralization of enamel and dentin in the oral environment. Thus, the aim of this review is to explore the broad role of sucrose in the cariogenicity of biofilms, and to present a new insight into its influence on the pathogenesis of dental caries.


Assuntos
Biofilmes , Cariogênicos/efeitos adversos , Cárie Dentária/etiologia , Sacarose Alimentar/efeitos adversos , Polissacarídeos/metabolismo , Cariogênicos/metabolismo , Esmalte Dentário/metabolismo , Placa Dentária/complicações , Placa Dentária/metabolismo , Sacarose Alimentar/metabolismo , Humanos , Desmineralização do Dente/etiologia , Desmineralização do Dente/metabolismo
12.
Cancer Res ; 56(11): 2484-7, 1996 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-8653681

RESUMO

Patients with head and neck cancers have a high (2-3%/year) incidence of second primary lesions. Clinically, these new lesions are identified either simultaneously with the primary lesion (synchronous) or after a period of time (metachronous). This observation has been attributed to the concept of "field carcinogenesis," which is based on the hypothesis that prolonged exposure to carcinogens leads to the independent transformation of multiple epithelial cells at several sites. An alternative theory is based on the premise that any transforming event is rare; following initial transformation, the progeny of the transformed clone spread through the mucosa and give rise to geographically distinct but genetically related tumors. We analyzed the pattern of X-chromosome inactivation in multiple primary tumors from eight female patients with head and neck cancer. In addition, we used microsatellite analysis to examine the pattern of allelic loss on chromosomes 9p and 3p, identified as early events in the progression of head and neck malignancies. In four of four cases, multiple tumors demonstrated the same pattern of X-chromosome inactivation. In the remaining four cases, X-chromosome deletions prevented interpretation (n = 3), or the androgen receptor locus was noninformative (n = 1). In three of nine patients, multiple tumors displayed the same pattern of loss of heterozygosity, two with identical breakpoints on chromosome 9p. In one patient, there was an identical microsatellite alteration at a 3p locus, definitive evidence that these tumors arose from the same clone. Our findings suggest that in at least a proportion of patients with head and neck cancers, multiple primary tumors arise from a single clone.


Assuntos
Neoplasias de Cabeça e Pescoço/patologia , Neoplasias Primárias Múltiplas/patologia , Cromossomos Humanos Par 3 , Cromossomos Humanos Par 9 , Células Clonais , DNA de Neoplasias/genética , Mecanismo Genético de Compensação de Dose , Feminino , Marcadores Genéticos , Neoplasias de Cabeça e Pescoço/genética , Heterozigoto , Humanos , Repetições de Microssatélites , Deleção de Sequência
13.
Cancer Res ; 55(14): 2995-7, 1995 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-7541708

RESUMO

p16INK4A and p15INK4B were initially identified as potent inhibitors of activated cyclin/cyclin-dependent kinase complexes. These genes were colocalized to chromosome 9p21, and p16 was subsequently found to be mutated in familial melanoma and deleted in a wide variety of sporadic cancers. We recently found that de novo methylation of a 5' CpG island led to transcriptional block of full-length p16 in many neoplasms. However, the presence of a truncated p16 transcript in methylated cell lines led us to investigate the presence of an alternative promoter or initiation site. We have now identified an abundant alternative p16 transcript in both methylated and unmethylated cell lines generated from a novel sequence (exon 1 beta) potentially involved in the complex regulation of these critical cell cycle genes.


Assuntos
Proteínas de Transporte/genética , Transcrição Gênica , Sequência de Bases , Cromossomos Humanos Par 9 , Inibidor p16 de Quinase Dependente de Ciclina , DNA de Neoplasias/biossíntese , DNA de Neoplasias/genética , Éxons , Amplificação de Genes , Genes Supressores de Tumor , Humanos , Dados de Sequência Molecular , Neoplasias/genética , Reação em Cadeia da Polimerase , RNA/análise , RNA/genética , Análise de Sequência de DNA , Células Tumorais Cultivadas
14.
Cancer Res ; 55(9): 1811-6, 1995 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-7728743

RESUMO

Colorectal tumorigenesis proceeds through an accumulation of specific genetic alterations. Studies of the mechanism by which these genetic changes effect malignant transformation have focused on the deregulation of cell proliferation. However, colorectal epithelial homeostasis is dependent not only on the rate of cell production but also on apoptosis, a genetically programmed process of autonomous cell death. We investigated whether colorectal tumorigenesis involved an altered susceptibility to apoptosis by examining colorectal epithelium from normal mucosa, adenomas from familial adenomatous polyposis, sporadic adenomas, and carcinomas. The transformation of colorectal epithelium to carcinomas was associated with a progressive inhibition of apoptosis. The inhibition of apoptosis in colorectal cancers may contribute to tumor growth, promote neoplastic progression, and confer resistance to cytotoxic anticancer agents.


Assuntos
Apoptose/fisiologia , Transformação Celular Neoplásica/patologia , Neoplasias Colorretais/etiologia , Neoplasias Colorretais/patologia , Polipose Adenomatosa do Colo/genética , Polipose Adenomatosa do Colo/patologia , Transformação Celular Neoplásica/genética , Colo/citologia , Colo/fisiologia , Neoplasias Colorretais/genética , Células Epiteliais , Epitélio/patologia , Epitélio/fisiologia , Humanos , Mucosa Intestinal/citologia , Mucosa Intestinal/fisiologia , Mutação , Reto/citologia , Reto/fisiologia
15.
Cancer Res ; 58(20): 4531-6, 1998 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-9788595

RESUMO

The p53 tumor suppressor gene plays an instrumental role in transcriptional regulation of target genes involved in cellular stress responses. p53-dependent transactivation and transrepression require its interaction with p300/CBP, a coactivator that also interacts with the RelA subunit of nuclear factor-kappaB. We find that p53 inhibits RelA-dependent transactivation without altering RelA expression or inducible kappaB-DNA binding. p53-mediated repression of RelA is relieved by p300 overexpression and the increased RelA activity conferred by p53-deficiency is counteracted by either transactivation domain-deficient p300 fragments that bind RelA or a transdominant mutant of IkappaB alpha. Our results suggest that p53 can regulate diverse kappaB-dependent cellular responses.


Assuntos
Genes p53/fisiologia , Ligases/antagonistas & inibidores , Proteínas Nucleares/fisiologia , Transativadores/fisiologia , Proteína de Ligação a CREB , DNA/metabolismo , Humanos , Ligases/análise , Ligases/química , NF-kappa B/metabolismo , Transcrição Gênica
16.
Biochim Biophys Acta ; 842(1): 90-9, 1985 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-3899182

RESUMO

Four hybridoma cell lines have been established that secrete monoclonal antibodies to nonapeptide bradykinin. Bradykinin coupled to ovalbumin, using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide as coupling agent, was used to immunize BALB/c mice. Spleen cells from the immunized animals were fused to P3-X63-AG8-653 mouse myeloma cells. The resultant hybrid cells were screened by enzyme-linked immunoassay for production of antibodies to bradykinin. Hybrids from four positive wells were subcloned by limiting dilution and expanded as ascites tumor into pristane-primed mice. All the four hybrids secreted monoclonal antibodies of IgG1 (k) isotype. Unlabeled peptides bradykinin, lysyl-bradykinin (kallidin) and methionyl-lysyl-bradykinin competed with the radiolabeled [Tyr1]kallidin for monoclonal antibody binding sites. These antibodies recognized preferentially either NH2- or COOH-terminals of the nonapeptide bradykinin and can distinguish between des-Arg1-bradykinin and des-Arg9-bradykinin. Bradykinin fragments smaller than eight residues were not recognized by these antibodies. Monoclonal antibodies BK-D6A5, BK-B6C9 and BK-A3D9 neutralized the smooth muscle contractile activity of bradykinin. An enzyme-linked immunoassay developed using these monoclonal antibodies showed the effective range of bradykinin determination between 5 and 150 ng.


Assuntos
Anticorpos Monoclonais/imunologia , Bradicinina/imunologia , Animais , Especificidade de Anticorpos , Bradicinina/análogos & derivados , Reações Cruzadas , Técnicas Imunoenzimáticas , Cininogênios/imunologia , Camundongos , Contração Muscular , Músculo Liso/fisiologia
17.
Biochim Biophys Acta ; 1208(2): 316-23, 1994 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-7947964

RESUMO

The complete carbohydrate structure of the asparagine-linked oligosaccharides of rat plasma thiostatin was elucidated through chemical and enzymatic methods including gas chromatography-mass spectrometry (GC-MS) and lectin affinity chromatography. Pronase digestion of thiostatin yielded a major glycopeptide fraction with asparagine the most abundant amino acid present. Based on one mole of aspartic acid, the following molar ratios obtained for the four major amino acids: aspartic acid (1.0), threonine (0.53), glycine (0.48) and serine (0.30). Neutral sugar analysis yielded a 3:2 molar ratio for mannose to galactose based on an assigned value to mannose of 3. On this basis, the fraction also contained 3 residues of sialic acid and, on average, 0 to 1 residue of fucose. GC-MS of partially methylated alditol acetates from the glycopeptide fraction identified the presence of biantennary and triantennary structure. Analyses of the neutral sugar and amino-acid composition, together with methylation data, support a biantennary N-linked structure for this major glycopeptide fraction and a triantennary N-linked structure as a lesser component. Sequencing of the desialyated 14C-labelled glycopeptide fraction by sequential exoglycosidase digestion and lectin affinity chromatography uncovered the following saccharide order: terminal galactose, N-acetylglucosamine and pentasaccharide inner core. This sequence is consistent with the N-linked glycan structures demonstrated by methylation and compositional analyses.


Assuntos
Asparagina/química , Cininogênios/química , Oligossacarídeos/química , Aminoácidos/análise , Animais , Sequência de Carboidratos , Carboidratos/análise , Glicopeptídeos/isolamento & purificação , Glicosídeo Hidrolases , Cininogênios/sangue , Cininogênios/isolamento & purificação , Dados de Sequência Molecular , Pronase , Ratos , Álcoois Açúcares/análise
18.
Clin Cancer Res ; 1(3): 257-60, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9815980

RESUMO

Kaposi's sarcoma is generally believed to be a non-neoplastic hyperproliferation because it may regress spontaneously and its spindle cells lack features of typical tumor cells, such as aneuploidy, nuclear atypia, and permissive growth in cell culture. A fundamental characteristic of neoplasms is clonality, in that they arise from clonal replication of a single cell whereas reactive processes are derived from polyclonal proliferation. We used an X chromosome inactivation assay to determine the clonality of Kaposi's sarcoma nodules from patients with AIDS-related disease. The assay is based on a methyl-sensitive restriction digest followed by PCR amplification of the highly polymorphic androgen receptor gene. Two of three evaluable cases had a monoclonal pattern of inactivation, and the third case had a clonal expansion of cells with an altered microsatellite repeat sequence. These data suggest that Kaposi's sarcoma (at least in the AIDS setting) is a clonal neoplasm.


Assuntos
Síndrome da Imunodeficiência Adquirida/complicações , Soropositividade para HIV/complicações , Sarcoma de Kaposi/genética , Sarcoma de Kaposi/patologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Biópsia , DNA de Neoplasias/genética , Feminino , HIV-1 , Humanos , Regressão Neoplásica Espontânea , Reação em Cadeia da Polimerase , Receptores Androgênicos/genética , Mapeamento por Restrição , Cromossomo X
19.
J Histochem Cytochem ; 37(4): 515-28, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2926128

RESUMO

We studied the subcellular localization of two major secretory products of adult rat submandibular gland (RSMG), blood group A-reactive mucin glycoprotein and glutamine/glutamic acid-rich protein (GRP), by light and electron microscopic immunocytochemistry. The structure of the major neutral oligosaccharide of the mucin was shown to be: GalNAc alpha 1,3(Fuc alpha 1,2)Gal beta 1,3GalNAc. A mouse monoclonal antibody (1F9) with specificity for blood group A determinants was prepared against the mucin. The antibody recognized a single band of approximately 114 KD on Western blots of RSMG extract. A previously characterized monoclonal antibody (59) against GRP (Mirels et al.: J Biol Chem 262: 7289, 1987) reacted with a doublet of 45-50 KD on Western blots of extraparotid saliva. Immunofluorescence and immunoperoxidase staining of cryostat sections of RSMG with anti-mucin antibodies and anti-GRP antibodies revealed reactivity in acinar cells of the gland. No specific labeling was seen in duct cells of RSMG or in mucous acinar cells of the adjacent sublingual gland. Post-embedding immunogold labeling of thin sections of glutaraldehyde-fixed RSMG with anti-mucin showed strong labeling of the Golgi apparatus and secretory granules of acinar cells. Gold particles were seen mainly over electron-lucent areas of the granules. No labeling occurred over the endoplasmic reticulum. The labeling pattern with the anti-GRP antibodies was similar, except that both electron-dense and -lucent areas of the granules were labeled, and the endoplasmic reticulum was reactive. Double labeling with two different sizes of gold particles showed that both mucin and GRP co-localized in the same granules. Pre-absorption of the antibodies with their respective antigens eliminated immunolabeling of the acinar cells. These antibodies will be useful in studies of cell differentiation in RSMG and of synthesis, processing, and packaging of RSMG secretory products.


Assuntos
Glutamatos/metabolismo , Glutamina/metabolismo , Mucinas/metabolismo , Glândula Submandibular/metabolismo , Animais , Anticorpos Monoclonais/análise , Imuno-Histoquímica , Masculino , Microscopia Eletrônica , Mucinas/análise , Ratos , Ratos Endogâmicos , Glândula Submandibular/citologia , Glândula Submandibular/ultraestrutura
20.
Biochem Pharmacol ; 32(13): 2061-9, 1983 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-6870934

RESUMO

Low molecular weight (LMW) kininogen was purified 70-fold with a 16% yield from fresh rat plasma by DEAE-Sephadex chromatography, ammonium sulfate precipitation, Sephadex G-200 gel filtration, SP-Sephadex chromatography, CM-cellulose chromatography, and Sephadex G-200 gel filtration. Ferguson plots of polyacrylamide gel electrophoretic patterns revealed four bands with relative molecular weights of 64,000, 123,500, 252,436 and 357,900 (ratio of 1:2:4:6). Sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis provided a single protein band with a molecular weight of 72,000, suggesting that the four kininogen bands had been caused by the aggregation of a single oligomeric protein. The purified LMW rat kininogen Fraction B (3.9 micrograms bradykinin/mg) was used to elicit an antiserum in the rabbit. Monospecificity of the antiserum was demonstrated by immunoelectrophoresis (Laurell rocket and Grabar methods) and, thus, the homogeneity of the kininogen was also. The purified kininogen (both Fractions A and B) formed kinin with human urinary kallikrein, rat urinary kallikrein and hog pancreatic kallikrein. Murphy-Sturm lymphosarcoma acid protease also formed kinin when incubated with the kininogen at pH 3.0. The isoelectric point for both fractions was at pH 4.3. Amino acid analyses showed the two kininogen fractions to be rich in acidic amino acids and to have a total carbohydrate content of 8.5% consisting of galactose (1.2 to 1.5%), mannose (1.9 to 2.1%), N-acetylglucosamine (4.3 to 5.1%), N-acetylgalactosamine (0.3%), and sialic acid (0.68%).


Assuntos
Cininogênios/sangue , Aminoácidos/análise , Animais , Carboidratos/análise , Fenômenos Químicos , Precipitação Química , Química , Cromatografia em Gel , Cromatografia por Troca Iônica , Eletroforese em Gel de Poliacrilamida , Imunoeletroforese , Focalização Isoelétrica , Cininogênios/isolamento & purificação , Cininas/metabolismo , Peso Molecular , Ratos
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