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2.
Clin Exp Immunol ; 123(1): 170-7, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11168015

RESUMO

ANCA with specificity for proteinase 3 (PR3), a neutrophil primary granule enzyme, are of diagnostic value in Wegener's granulomatosis (WG) and certain other forms of systemic vasculitis. There is evidence to suggest that they play a pathogenic role in disease, and that the interaction of ANCA with PR3 is likely to be important. We showed, using a resonant mirror biosensor, that C-ANCA from different patients recognized the same or closely related epitopes on PR3. Studies using linear peptides in the SPOT system confirmed the highly restricted nature of this interaction and identified five linear epitopes. Fluid-phase inhibition studies, using a different set of peptides, validated the sequences involved. Using a computer-generated model of the structure of PR3, four of five epitopes were shown to be intimately linked with the catalytic site. The restricted number of epitopes, and their location at the catalytic site, has important implications for the role of C-ANCA in the pathogenesis of vasculitis.


Assuntos
Anticorpos Anticitoplasma de Neutrófilos/metabolismo , Domínio Catalítico/imunologia , Epitopos/imunologia , Serina Endopeptidases/imunologia , Vasculite/enzimologia , Vasculite/imunologia , Sequência de Aminoácidos , Sítios de Ligação de Anticorpos , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Colódio , Enzimas Imobilizadas/química , Enzimas Imobilizadas/imunologia , Enzimas Imobilizadas/metabolismo , Humanos , Membranas Artificiais , Modelos Moleculares , Dados de Sequência Molecular , Mieloblastina , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/imunologia , Fragmentos de Peptídeos/metabolismo , Estrutura Terciária de Proteína , Serina Endopeptidases/química , Serina Endopeptidases/metabolismo , Eletricidade Estática
3.
Development ; 126(24): 5635-44, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10572040

RESUMO

PETAL LOSS is a new class of flower development gene whose mutant phenotype is confined mostly to the second whorl. Two properties are disrupted, organ initiation and organ orientation. Initiation is frequently blocked, especially in later-formed flowers, or variably delayed. The few petals that arise occupy a wider zone of the flower primordium than normal. Also, a minority of petals are trumpet-shaped, thread-like or stamenoid. Studies of ptl combined with homeotic mutants have revealed that the mutant effect is specific to the second whorl, not to organs with a petal identity. We propose that the PTL gene normally promotes the induction of organ primordia in specific regions of the second floral whorl. In ptl mutants, these regions are enlarged and organ induction is variably reduced, often falling below a threshold. A dominant genetic modifier of the ptl mutant phenotype was found in the Landsberg erecta strain that significantly boosts the mean number of petals per flower, perhaps by reinforcing induction so that the threshold is now more often reached. The second major disruption in ptl mutants relates to the orientation adopted by second whorl organs from early in their development. In single mutants the full range of orientations is seen, but when B function (controlling organ identity) is also removed, most second whorl organs now face outwards rather than inwards. Orientation is unaffected in B function single mutants. Thus petals apparently perceive their orientation within the flower primordium by a mechanism requiring PTL function supported redundantly by that of B class genes.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Genes de Plantas , Arabidopsis/ultraestrutura , Mutagênese , Fenótipo , Proteínas de Plantas/genética , Estruturas Vegetais/crescimento & desenvolvimento
4.
Am J Infect Control ; 27(2): 91-6, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10196485

RESUMO

BACKGROUND: A large number (17) of nosocomial respiratory syncytial virus cases led to the development of control measures to prevent transmission of respiratory syncytial virus (RSV) within the Johns Hopkins Hospital's Children's Center. METHODS: The control plan is based on a 2-stage process. In stage 1, the staff are notified that RSV is in the community, and information is distributed through a communication tree. Stage 2 requires that nasopharyngeal aspirates be obtained from all children <3 years of age who have respiratory symptoms. The aspirates are tested directly for RSV antigen and cultured for RSV. The children are placed on pediatric droplet precautions pending those results. RESULTS: The proportion of nosocomial RSV cases dropped from 16.5% before the use of RSV control measures to 7.2% after the initiation of the control program. A case of RSV identified in the hospital was 2.6 times more likely to be nosocomially acquired before the intervention compared with after the intervention. Approximately 14 cases of RSV are prevented each year, which results in a savings of 56 hospital-days and more than $84,000 in direct hospital-related charges alone. CONCLUSIONS: The nosocomial spread of RSV can be reduced by a specific and feasible control plan that includes early identification and rapid isolation of potential RSV cases.


Assuntos
Infecção Hospitalar/prevenção & controle , Controle de Infecções/métodos , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Infecções por Vírus Respiratório Sincicial/transmissão , Baltimore , Pré-Escolar , Infecção Hospitalar/diagnóstico , Feminino , Hospitais Universitários/estatística & dados numéricos , Humanos , Lactente , Recém-Nascido , Masculino , Infecções por Vírus Respiratório Sincicial/diagnóstico
5.
Psychosomatics ; 39(2): 144-53, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9584540

RESUMO

Fourteen videotaped family interviews of patients with diagnosed pseudoseizures were studied to determine the relationship of the symptoms to unspeakable dilemmas as forced choices imposed by family or social circumstances under conditions that also require the ensuing distress to be hidden. An unspeakable dilemma was evident in 13 of 14 interviews, with the patient the most silent family member in 13 interviews. In six cases, there was revealed a realistic threat of physical or sexual assault to a person involved in the problem, although not always the patient. These findings point to an important role for family therapy skills in the evaluation and treatment of pseudoseizures.


Assuntos
Saúde da Família , Família/psicologia , Convulsões/psicologia , Adolescente , Adulto , Criança , Transtorno Conversivo/complicações , Transtornos Autoinduzidos/complicações , Terapia Familiar , Feminino , Humanos , Estudos Retrospectivos , Convulsões/complicações , Convulsões/terapia , Transtornos Somatoformes/complicações
6.
Exp Clin Immunogenet ; 14(3): 196-205, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9493788

RESUMO

Primary systemic vasculitis affecting smaller vessels is usually associated with antineutrophil cytoplasmic antibodies (ANCA). The ANCA-associated vasculitides include Wegener's granulomatosis, microscopic polyangiitis, Churg Strauss syndrome and renal limited vasculitis. There is considerable evidence that genetic factors influence susceptibility to ANCA-associated vasculitis, including reports of familial cases, differences in racial incidence, and associations with polymorphic variants of proteins such as alpha-1-antitrypsin. There is mounting evidence, from clinical and in vitro studies, that ANCA may be pathogenic. However, it is also clear that autoreactive T cells are likely to be involved, by providing T cell help for ANCA production and possibly by producing cell-mediated immune injury. Indeed, T cells from patients with vasculitis have been shown to proliferate in vitro in response to the target antigens of ANCA - proteinase 3 and myeloperoxidase. In most T-cell-dependent autoimmune diseases there are clear positive and/or negative associations with HLA genes. These genes are encoded in the major histocompatibility complex (MHC) and their products, the HLA molecules, play a central role in the generation of T cell responses. For this reason, many investigators have looked for HLA associations in ANCA-associated vasculitides. Problems in analysing these reports include the definition of the diseases concerned, and the varying methodology of HLA typing. A number of positive and negative associations with HLA genes have been reported in systemic vasculitis. However, it is striking that no consistent association has been identified in different series. In recent studies there have been positive associations with HLA DR1, DQw7 or DR8, negative associations with DR3 or DR13, or no significant associations. This lack of an obvious and consistent HLA association is extremely interesting, and suggests that the T cell response in vasculitis may be very heterogeneous, or that a genuine strong association has yet to be identified. Further investigation of this problem is clearly needed to improve our understanding of the pathogenesis of ANCA-associated vasculitides.


Assuntos
Anticorpos Anticitoplasma de Neutrófilos/imunologia , Antígenos HLA/genética , Vasculite/genética , Autoimunidade/imunologia , Humanos , Tolerância Imunológica , Vasculite/imunologia
7.
Ren Fail ; 18(5): 785-802, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8903093

RESUMO

Patients with systemic vasculitis (SV), especially Wegener's granulomatosis and microscopic polyangiitis, regularly present with renal involvement. Although considered a rare disease, either the incidence of SV is increasing or it is being increasingly recognized. Accurate classification systems are required to allow comparison of data from different groups investigating and treating these patients. Systemic vasculitis is known to be an autoimmune disease, but the mechanisms of pathogenesis have not been established, despite many studies on this topic in recent years. Most of this work has been done in vitro, although development of animal models is underway. Patient and renal survival have improved with aggressive immunosuppressive treatment, but morbidity is high and controversies remain in establishing the most effective regimens with minimum adverse effects. In this review we discuss the classification of SV, review the current knowledge of pathogenic mechanisms, and consider the relative merits of different treatment protocols.


Assuntos
Rim/irrigação sanguínea , Vasculite , Animais , Terapia Combinada , Humanos , Indução de Remissão/métodos , Vasculite/classificação , Vasculite/etiologia , Vasculite/terapia
8.
Nephrol Dial Transplant ; 11(3): 438-43, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8671812

RESUMO

BACKGROUND: Antineutrophil cytoplasmic antibodies (ANCA) in vasculitis have either cANCA or pANCA patterns as defined by immunofluorescence. The target autoantigen of cANCA is usually proteinase 3 (PR3), whereas that of pANCA is usually myeloperoxidase (MPO). Alpha-1-antitrypsin (alpha 1AT) is the major physiological inhibitor of PR3, while MPO is an inhibitor of alpha 1AT. METHODS: To determine whether there was an association between ANCA positive vasculitis, ANCA pattern, and alpha 1AT deficiency alleles, we studied alpha 1AT phenotypes of 99 cANCA and 99 pANCA positive vasculitis patients by isoelectric focusing and immunoblotting, and compared them with 2310 controls from the same geographical area. RESULTS: C-ANCA patients showed an increased frequency of the Z allele (0.055 versus 0.018 in controls), conferring a relative risk of 3. They showed no increase in frequency of the S allele. P-ANCA patients showed an increased frequency of the S allele (0.091 versus 0.046 in controls) conferring a relative risk of 2. The frequency of the Z allele also appeared to be increased (0.030 versus 0.018 in controls), but this was not statistically significant. CONCLUSIONS: These findings demonstrate an association between ANCA-positive vasculitis and deficiency phenotypes of alpha 1AT, and suggest a role for alpha 1AT in the development of systemic vasculitis.


Assuntos
Alelos , Autoanticorpos/imunologia , Inibidores da Tripsina/genética , Vasculite/enzimologia , Vasculite/imunologia , alfa 1-Antitripsina/genética , Anticorpos Anticitoplasma de Neutrófilos , Autoantígenos/genética , Autoantígenos/metabolismo , DNA/análise , Ensaio de Imunoadsorção Enzimática , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Focalização Isoelétrica , Mieloblastina , Peroxidase/genética , Peroxidase/metabolismo , Fenótipo , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Inibidores da Tripsina/metabolismo , Vasculite/genética , alfa 1-Antitripsina/metabolismo
9.
Clin Exp Immunol ; 103(2): 253-8, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8565308

RESUMO

T cell-mediated immune responses are likely to be important in the pathogenesis of systemic vasculitis. However, identifying the T cells involved has proved difficult, and there are conflicting reports regarding T cell proliferation in response to different autoantigens. Perinuclear (P) and cytoplasmic (C) anti-neutrophil cytoplasmic antibodies (ANCA) are closely associated with systemic vasculitis, and are generally specific for MPO or PR3, respectively. We studied the proliferative responses to MPO and PR3 of peripheral blood mononuclear cells from patients with P-ANCA or C-ANCA specific for these antigens by ELISA. These responses were compared with those of normal controls, and of disease controls with P- or C-ANCA not specific for MPO or PR3. The patient group as a whole showed significant T cell proliferation in response to the autoantigens compared with controls (P = 0.005). Cells from nine of 13 P-ANCA-positive, anti-MPO-positive patients proliferated in response to MPO, compared with five of 16 controls (P = 0.04). Cells from five of eight C-ANCA-positive, anti-PR3-positive patients proliferated in response to PR3, compared with two of 11 controls (P = 0.05). These experiments demonstrate that patients with P-ANCA or C-ANCA possess T cells which respond to MPO or PR3, respectively. As in other autoimmune diseases, responses to both antigens were also seen in a proportion of healthy controls. Further analysis of these responses will be important in understanding the pathogenesis of systemic vasculitis and in designing specific immunotherapy.


Assuntos
Autoanticorpos/imunologia , Peroxidase/farmacologia , Serina Endopeptidases/farmacologia , Linfócitos T/patologia , Vasculite/imunologia , Divisão Celular/efeitos dos fármacos , Núcleo Celular/imunologia , Células Cultivadas , Citoplasma/imunologia , Humanos , Mieloblastina , Neutrófilos/imunologia , Neutrófilos/ultraestrutura , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia
10.
Antimicrob Agents Chemother ; 36(11): 2398-402, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1489183

RESUMO

Aqueous solutions of 0.02% isoniazid, 0.2% streptomycin, 0.2% para-aminosalicylate, and 0.5% ethambutol and ethylene glycol solutions of 0.5% ethionamide stored at 3 to 7 degrees C remained stable for 1 year, as did aqueous solutions of 0.05% ethionamide hydrochloride, 0.05% kanamycin, 0.05% viomycin, and 0.1% capreomycin stored at -20 degrees C. The ethambutol and capreomycin solutions were tested by microbiologic methods; the other solutions were tested by both spectrophotometric and microbiologic methods. Prepared susceptibility testing media made with cycloserine, rifampin, and the above solutions incorporated into Middlebrook 7H10 medium showed acceptable stability when stored at 3 to 7 degrees C for 1 month. During incubation of the test medium at 37 degrees C, approximately half of the activity of isoniazid, ethionamide, ethambutol, cycloserine, and rifampin was lost after periods ranging from 2 to 4 days for ethambutol to 2 weeks for rifampin.


Assuntos
Antituberculosos/química , Antituberculosos/farmacologia , Química Farmacêutica , Temperatura Baixa , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Congelamento , Isoniazida/química , Isoniazida/farmacologia , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/efeitos dos fármacos , Soluções/química , Temperatura , Fatores de Tempo
11.
Fam Process ; 29(1): 13-28, 1990 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2311750

RESUMO

Using detailed case examples, we contrast first- and second-order cybernetics approaches to family problems involving somatic symptoms in a family member. A second-order cybernetics approach views the reality of the problem as linguistically shaped by those interacting around it, including the therapist and observing team members. This co-constructed reality, the story of the problem, inadvertently contributes to the problem's endurance by narrowing the choice of more effective solutions. In our approach, the therapist elicits from each person his or her story about the illness in the family. The therapist then facilitates a therapeutic conversation that provides a context for new linguistic distinctions to be drawn, including the way mind and body may interact to generate the symptoms. Shifts in beliefs and behaviors follow, and more innovative solutions to the problem can then emerge. Unlike the approach in our previously published work based upon ecosystemic patterns as "system diagnoses," this approach uses only descriptions and explanations of the problem as are collaboratively constructed within this therapeutic conversation.


Assuntos
Cibernética , Terapia Familiar/métodos , Transtornos de Enxaqueca/psicologia , Estresse Psicológico/psicologia , Adulto , Atitude do Pessoal de Saúde , Autoritarismo , Feminino , Humanos , Transtornos de Enxaqueca/etiologia , Transtornos de Enxaqueca/terapia , Semântica , Estresse Psicológico/complicações
12.
Fam Process ; 28(2): 137-52, 1989 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2659387

RESUMO

Effective ways for joining family therapy with other treatment modalities are becoming increasingly important as the efficacy of family therapy gains acceptance in the medical and mental health community. When one interfaces family therapy with medical and psychopharmacological treatments, which find the sources of symptoms within individuals, rather than interpersonal systems, careful attention must be paid to the mind and body relationships that guide interactions between family behavior and the somatic physiology of each family member. We present six mind-body patterns of symptom generation found to be particularly useful for designing multimodality treatments and for communicating the treatment rationale to medical and psychiatric clinicians or to family members. Case examples illustrate their clinical use.


Assuntos
Terapia Familiar/métodos , Terapia Combinada , Cibernética , Humanos , Neuropsicologia , Psicofisiologia , Papel do Doente , Teoria de Sistemas
13.
J Clin Microbiol ; 26(11): 2338-42, 1988 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3235659

RESUMO

The acceptability of different lots of commercial components which constitute our basal medium for susceptibility testing of mycobacteria was evaluated. The basal medium consisted of Middlebrook 7H10 agar supplemented with 10% oleic acid-albumin-dextrose-catalase and 0.5% glycerol. Studies were performed by using three separate microbiologic assays, and results were compared with parallel tests on previously standardized and acceptable lots of media. Components were rejected if comparison with standardized medium showed a major change in growth support or susceptibility status of any reference strain to any antimicrobial agent tested. Of the components tested in such a manner, 7 of 23 (30%) lots of 10% oleic acid-albumin-dextrose-catalase, 2 of 13 (15%) lots of Middlebrook 7H10 agar, and 0 of 5 lots of glycerol were found to be unacceptable. This study demonstrates that individual lots of components of this basal medium may vary significantly in their suitability for susceptibility testing, and failure to detect such variation may dramatically affect susceptibility profiles.


Assuntos
Antibacterianos/farmacologia , Mycobacterium/efeitos dos fármacos , Meios de Cultura , Indicadores e Reagentes , Testes de Sensibilidade Microbiana/métodos , Testes de Sensibilidade Microbiana/normas , Mycobacterium/crescimento & desenvolvimento , Controle de Qualidade
14.
Clin Sci (Lond) ; 75(5): 489-94, 1988 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2855478

RESUMO

1. The relationship between plasma immunoreactive atrial natriuretic factor (Ir-ANF) and the urinary excretion of sodium, guanosine 3':5'-cyclic monophosphate (cyclic GMP) and of tissue kallikrein was examined in seven healthy female volunteers. 2. Each volunteer attended on two occasions, a control and a saline infusion day. On the infusion day saline (2 litres, 0.9% NaCl) was administered over 60 min. Measurements of plasma Ir-ANF and urinary excretion of sodium, cyclic GMP and of tissue kallikrein were made at 30 min intervals during the infusion and for 3 h after the infusion. 3. Mean (+/- SEM) urinary sodium excretion increased from a basal value (time 0) of 102 +/- 15 mumo/min to 222 +/- 47 mumol/min 60-90 min from the start of the infusion and thereafter remained significantly elevated (P less than 0.01) above sodium excretion on the control day. 4. In response to saline infusion there was a transient rise in mean (+/- SEM) plasma Ir-ANF from 6.7 +/- 0.8 pmol/l to a peak of 22.5 +/- 3.7 pmol/l at 75 min, falling to 12.7 +/- 1.9 pmol/l at 135 min. The peak plasma Ir-ANF level on the infusion day was significantly elevated (P less than 0.05) above the time-matched measurement on the control day. 5. Similarly, there was a transient rise in mean (+/- SEM) urinary cyclic GMP excretion on the infusion day from 30.9 +/- 4.4 fmol/min to 64.6 +/- 11.4 fmol/min during the 60-90 min collection period, returning to 43.7 +/- 14.5 fmol/min at 210-240 min.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Fator Natriurético Atrial/sangue , GMP Cíclico/urina , Calicreínas/urina , Adulto , Fator Natriurético Atrial/urina , GMP Cíclico/sangue , Feminino , Humanos , Calicreínas/sangue , Rim/metabolismo , Natriurese , Volume Plasmático , Sódio/sangue , Sódio/urina , Cloreto de Sódio/farmacologia , Calicreínas Teciduais
15.
J Clin Microbiol ; 26(2): 380-1, 1988 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3278000

RESUMO

Legionella gormanii, previously isolated only from the environment, was grown from the bronchial brush specimen of a patient with pneumonia. The organism was characterized by serologic, biochemical, and DNA hybridization studies.


Assuntos
Brônquios/microbiologia , Legionella/isolamento & purificação , Legionelose/microbiologia , Testes de Aglutinação , DNA Bacteriano/análise , Feminino , Imunofluorescência , Humanos , Tolerância Imunológica , Legionella/genética , Legionella/imunologia , Pessoa de Meia-Idade , Hibridização de Ácido Nucleico
16.
Ophthalmic Surg ; 19(1): 20-4, 1988 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3257554

RESUMO

Seventeen consecutive eyes with corneal epithelial basement membrane with symptoms of recurrent erosion and/or decreased vision were treated with corneal epithelial basement membranectomy. Younger patients tended to have recurrent erosion, whereas older patients had decreased vision. All patients' symptoms improved following surgery. Electron microscopy revealed reduplication of the corneal epithelial basal lamina.


Assuntos
Membrana Basal , Distrofias Hereditárias da Córnea/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Membrana Basal/cirurgia , Membrana Basal/ultraestrutura , Córnea/cirurgia , Córnea/ultraestrutura , Epitélio/cirurgia , Epitélio/ultraestrutura , Feminino , Seguimentos , Humanos , Microscopia Eletrônica , Pessoa de Meia-Idade , Fatores de Tempo
20.
J Bacteriol ; 108(3): 1154-60, 1971 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-5139535

RESUMO

Penicillin-resistant mutants of Staphylococcus aureus H were similar to the parent in their response to penicillin though proportionately more penicillin was required for a given effect. The mutants did not inactivate penicillin. Most of the penicillin-binding sites (presumed to be murein transpeptidase molecules) bound penicillin rapidly when exposed to a very low concentration of penicillin (0.1 mug/ml), and yet the mutants retained some functional murein transpeptidase even in the presence of 500 mug of penicillin per ml. An hypothesis based on (i) functional versus nonfunctional transpeptidase molecules and (ii) variations in accessibility to penicillin can explain these findings.


Assuntos
Mutação , Penicilina G/farmacologia , Resistência às Penicilinas , Penicilinase/metabolismo , Staphylococcus/efeitos dos fármacos , Aminoácidos/análise , Amino Açúcares/análise , Proteínas de Bactérias/análise , Proteínas de Bactérias/biossíntese , Sítios de Ligação , Isótopos de Carbono , Parede Celular/análise , Cromatografia em Papel , Meios de Cultura , Genética Microbiana , Hidrólise , Lisina/metabolismo , Penicilina G/metabolismo , Peptídeo Hidrolases/metabolismo , Peptidoglicano/biossíntese , Staphylococcus/análise , Staphylococcus/enzimologia , Staphylococcus/crescimento & desenvolvimento , Staphylococcus/metabolismo
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