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1.
Hum Reprod ; 37(12): 2768-2776, 2022 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-36223599

RESUMO

STUDY QUESTION: Is a strategy starting with transvaginal hydrolaparoscopy (THL) cost-effective compared to a strategy starting with hysterosalpingography (HSG) in the work-up for subfertility? SUMMARY ANSWER: A strategy starting with THL is cost-effective compared to a strategy starting with HSG in the work-up for subfertile women. WHAT IS KNOWN ALREADY: Tubal pathology is a common cause of subfertility and tubal patency testing is one of the cornerstones of the fertility work-up. Both THL and HSG are safe procedures and can be used as a first-line tubal patency test. STUDY DESIGN, SIZE, DURATION: This economic evaluation was performed alongside a randomized clinical trial comparing THL and HSG in 300 subfertile women, between May 2013 and October 2016. For comparisons of THL and HSG, the unit costs were split into three main categories: costs of the diagnostic procedure, costs of fertility treatments and the costs for pregnancy outcomes. PARTICIPANTS/MATERIALS, SETTING, METHODS: Subfertile women scheduled for tubal patency testing were eligible. Women were randomized to a strategy starting with THL or a strategy starting with HSG. The primary outcome of the study was conception leading to a live birth within 24 months after randomization. The mean costs and outcomes for each treatment group were compared. We used a non-parametric bootstrap resampling of 1000 re-samples to investigate the effect of uncertainty and we created a cost-effectiveness plane and cost-effectiveness acceptability curves. MAIN RESULTS AND THE ROLE OF CHANCE: We allocated 149 women to THL and 151 to HSG, and we were able to achieve complete follow-up of 142 versus 148 women, respectively. After the fertility work-up women were treated according to the Dutch guidelines and based on a previously published prognostic model. In the THL group, 83 women (58.4%) conceived a live born child within 24 months after randomization compared to 82 women (55.4%) in the HSG group (difference 3.0% (95% CI: -8.3 to 14.4)). The mean total costs per woman were lower in the THL group compared to the HSG group (THL group €4991 versus €5262 in the HSG group, mean cost difference = -€271 (95% CI -€273 to -€269)). Although the costs of only the diagnostic procedure were higher in the THL group, in the HSG group more women underwent diagnostic and therapeutic laparoscopies and also had higher costs for fertility treatments. LIMITATIONS, REASONS FOR CAUTION: Our trial was conducted in women with a low risk of tubal pathology; therefore, the results of our study are not generalizable to women with high risk of tubal pathology. Furthermore, this economic analysis was based on the Dutch healthcare system, and possibly our results are not generalizable to countries with different strategies or costs for fertility treatments. WIDER IMPLICATIONS OF THE FINDINGS: After 2 years of follow-up, we found a live birth rate of 58.4% in the THL group versus 55.4% in the HSG group and a lower mean cost per woman in the THL group, with a cost difference of -€271. The findings of our trial suggest that a strategy starting with THL is cost-effective compared to a strategy starting with HSG in the workup for subfertile women. However, the cost difference between the two diagnostic strategies is limited compared to the total cost per woman in our study and before implementing THL as a first-line strategy for tubal patency testing, more research in other fields, such as patient preference and acceptance, is necessary. STUDY FUNDING/COMPETING INTEREST(S): The authors received no external financial support for the research. B.W.J.M. is supported by an NHMRC Investigator Grant (GNT1176437). B.W.J.M. reports consultancy for ObsEva, Merck KGaA, Guerbet. B.W.J.M. reports receiving travel support from Merck KGaA. C.T.P. reports consultancy for Guerbet, outside of this manuscript. All other authors have no conflicts to declare. TRIAL REGISTRATION NUMBER: NTR3462.


Assuntos
Histerossalpingografia , Infertilidade , Feminino , Humanos , Gravidez , Coeficiente de Natalidade , Análise Custo-Benefício , Nascido Vivo
2.
Dalton Trans ; 45(26): 10771-9, 2016 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-27292266

RESUMO

Similar reactions of 2,6-dipicolinoylbis(N,N-diethylthiourea) (H2L(a)) with: (i) Ni(NO3)2·6H2O, (ii) a mixture of Ni(NO3)2·6H2O and AgNO3, (iii) a mixture of Ni(OAc)2·4H2O and PrCl3·7H2O and (iv) a mixture of Ni(OAc)2·4H2O and BaCl2·2H2O give the binuclear complex [Ni2(L(a))2(MeOH)(H2O)], the polymeric compound [NiAg2(L(a))2]∞, and the heterobimetallic complexes [Ni2Pr(L(a))2(OAc)3] and [Ni2Ba(L(a))3], respectively. The obtained assemblies can be used for the build up of supramolecular polymers by means of weak and medium intermolecular interactions. Two prototype examples of such compounds, which are derived from the trinuclear complexes of the types [MLn(III)(L)2(OAc)3] and [MBa(L)3], are described with the compounds {[CuDy(III)(L(a))2(p-O2C-C6H4-CO2)(MeOH)4]Cl}∞ and [MnBa(MeOH)(L(b))3]∞, H2L(b) = 2,6-dipicolinoylbis(N,N-morpholinoylthiourea).

3.
Artigo em Inglês | MEDLINE | ID: mdl-26274114

RESUMO

A water cylinder deposited on a heated channel levitates on its own generated vapor film owing to the Leidenfrost effect. This experimental setup permits the study of the one-dimensional propagation of surface waves in a free-to-move liquid system. We report the observation of gravity-capillary waves under a dramatic reduction of gravity (up to a factor 30), leading to capillary waves at the centimeter scale. The generated nonlinear structures propagate without deformation and undergo mutual collisions and reflections at the boundaries of the domain. They are identified as Korteweg-de Vries solitons with negative amplitude and subsonic velocity. The typical width and amplitude-dependent velocities are in excellent agreement with theoretical predictions based on a generalized Korteweg-de Vries equation adapted to any substrate geometry. When multiple solitons are present, they interact and form a soliton turbulencelike spectrum.


Assuntos
Ação Capilar , Hidrodinâmica , Modelos Teóricos , Água , Gravitação , Dinâmica não Linear
4.
Phys Rev E Stat Nonlin Soft Matter Phys ; 84(2 Pt 1): 021701, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21928999

RESUMO

Close to sinusoidal substrates, simple fluids may undergo a filling transition, in which the fluid passes from a dry to a filled state, where the interface remains unbent but bound to the substrate. Increasing the surface field, the interface unbinds and a wetting transition occurs. We show that this double-transition sequence may be strongly modified in the case of ordered fluids, such as nematic liquid crystals. Depending on the preferred orientation of the nematic molecules at the structured substrate and at the isotropic-nematic interface, the filling transition may not exist, and the fluid passes directly from a dry to a complete-wet state, with the interface far from the substrate. More interestingly, in other situations, the complete wetting transition may be prevented, and the fluid passes from a dry to a filled state, and remains in this configuration, with the interface always attached to the substrate, even for very large surface fields. Both transitions are observed only for a same substrate in a narrow range of amplitudes.

6.
J Dent Res ; 88(4): 323-7, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19407151

RESUMO

Kallikrein-4 (KLK4) is a serine protease expressed during enamel maturation, and proteolytic processing of the enamel matrix by KLK4 is critical for proper enamel formation. KLK4 is secreted as an inactive zymogen (pro-KLK4), and identification of its activator remains elusive. Dipeptidyl peptidase I (DPPI) is a cysteine aminopeptidase that can activate several serine proteases. In this study, we sought to examine DPPI expression in mouse enamel organ and determine if DPPI could activate KLK4. Real-time PCR showed DPPI expression throughout amelogenesis, with highest expression at maturation, and immunohistochemical staining of mouse incisors confirmed DPPI expression by ameloblasts. We demonstrate in vitro that DPPI activates pro-KLK4 to cleave a fluorogenic peptide containing a KLK4 cleavage site. Examination of mature enamel from DPPI null mice by FTIR showed no significant accumulation of protein; however, microhardness testing revealed that loss of DPPI expression significantly reduced enamel hardness.


Assuntos
Amelogênese/fisiologia , Catepsina C/metabolismo , Esmalte Dentário/enzimologia , Calicreínas/metabolismo , Calcificação de Dente/fisiologia , Amelogênese/genética , Animais , Catepsina C/genética , Esmalte Dentário/ultraestrutura , Proteínas do Esmalte Dentário/genética , Proteínas do Esmalte Dentário/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Calicreínas/genética , Mandíbula , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Camundongos Knockout , Camundongos Mutantes , Dente Molar/ultraestrutura , Proteínas Recombinantes , Especificidade da Espécie , Calcificação de Dente/genética
7.
Eur Phys J E Soft Matter ; 26(1-2): 97-101, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18414787

RESUMO

It is known that the wetting behaviour of a fluid is deeply altered by the presence of rough or structured substrates. We first review some simple considerations about isotropic fluids and rough substrates, and then we generalize Wenzel's law, which assigns an effective contact angle to a droplet on a rough substrate, when the wetting layer has an ordered phase, like a nematic. We estimate the conditions for which the wetting behavior of an ordered fluid can be qualitatively different from that usually found in a simple fluid. To support our general considerations, we use the Landau-de Gennes mean field approach to investigate theoretically and numerically the wetting transition of a nematic phase on a periodic triangular structured substrate.

8.
J Wound Care ; 15(6): 240-50, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16802559

RESUMO

Evidence on topical negative pressure from randomised controlled trials, non-randomised comparative studies and case studies is considered. This is the first systematic review on this therapy to consider results by wound type.


Assuntos
Segurança , Sucção/métodos , Cicatrização , Ferimentos e Lesões/terapia , Viés , Doença Crônica , Medicina Baseada em Evidências , Seguimentos , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa , Tamanho da Amostra , Transplante de Pele , Sucção/efeitos adversos , Resultado do Tratamento , Vácuo
9.
BJOG ; 110(2): 121-7, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12618154

RESUMO

OBJECTIVE: To determine if and to what extent postnatal women's preferences for birth outcomes differ from those of midwives and medical staff, and whether any variations in utility scores are associated with demographic variables. DESIGN: Cross sectional cohort study. SETTING: The Women's and Children's Hospital, Adelaide. POPULATION: A total of 180 participants which included 90 postnatal women, 59 midwives and 31 medical staff. METHODS: Preferences (utility scores) were measured by direct interviews using utility techniques: the visual analogue scale and the standard gamble. MAIN OUTCOMES MEASURES: Preferences (utility scores) for eight birth outcomes. RESULTS: Women assigned higher utility scores for the five birth outcomes of jaundice requiring phototherapy, admission to neonatal nursery, shoulder dystocia, nerve palsy and transient neurological symptoms than midwives, which suggested that women regarded these outcomes as less severe (P < 0.01). Utility scores for the women and medical staff were similar. The majority of postnatal women, midwives and medical staff preferred permanent neurological sequelae to perinatal death. Eighty-nine percent of postnatal women preferred permanent neurological sequelae to perinatal death compared with 71% of midwives (P < 0.01), and 68% of medical staff (P < 0.01). CONCLUSION: Utility values for important birth outcomes varied between women who had recently given birth and health professionals. Clinical practice should recognise and respect the preferences of women, with appropriate balance between their preferences, those of health professionals and the known benefits of care.


Assuntos
Atitude do Pessoal de Saúde , Atitude Frente a Saúde , Satisfação do Paciente , Resultado da Gravidez/psicologia , Adulto , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Masculino , Enfermeiros Obstétricos , Paridade , Cuidado Pós-Natal , Gravidez
10.
J Biol Chem ; 276(21): 18551-6, 2001 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-11279033

RESUMO

Dipeptidyl peptidase I (DPPI) is the sole activator in vivo of several granule-associated serine proteases of cytotoxic lymphocytes. In vitro, DPPI also activates mast cell chymases and tryptases. To determine whether DPPI is essential for their activation in vivo, we used enzyme histochemical and immunohistochemical approaches and solution-based activity assays to study these enzymes in tissues and bone marrow-derived mast cells (BMMCs) from DPPI +/+ and DPPI -/- mice. We find that DPPI -/- mast cells contain normal amounts of immunoreactive chymases but no chymase activity, indicating that DPPI is essential for chymase activation and suggesting that DPPI -/- mice are functional chymase knockouts. The absence of DPPI and chymase activity does not affect the growth, granularity, or staining characteristics of BMMCs and, despite prior predictions, does not alter IgE-mediated exocytosis of histamine. In contrast, the level of active tryptase (mMCP-6) in DPPI -/- BMMCs is 25% that of DPPI +/- BMMCs. These findings indicate that DPPI is not essential for mMCP-6 activation but does influence the total amount of active mMCP-6 in mast cells and therefore may be an important, but not exclusive mechanism for tryptase activation.


Assuntos
Catepsina C/metabolismo , Mastócitos/enzimologia , Serina Endopeptidases/metabolismo , Animais , Catepsina C/genética , Células Cultivadas , Quimases , Ativação Enzimática/genética , Deleção de Genes , Regulação Enzimológica da Expressão Gênica , Camundongos , Serina Endopeptidases/genética , Triptases
11.
Blood ; 94(12): 4282-93, 1999 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-10590073

RESUMO

Cathepsin G is a neutral serine protease that is highly expressed at the promyelocyte stage of myeloid development. We have developed a homologous recombination strategy to create a loss-of-function mutation for murine cathepsin G. Bone marrow derived from mice homozygous for this mutation had no detectable cathepsin G protein or activity, indicating that no other protease in bone marrow cells has the same specificity. Hematopoiesis in cathepsin G-/- mice is normal, and the mice have no overt abnormalities in blood clotting. Neutrophils derived from cathepsin G-/- mice have normal morphology and azurophil granule composition; these neutrophils also display normal phagocytosis and superoxide production and have normal chemotactic responses to C5a, fMLP, and interleukin-8. Although cathepsin G has previously shown to have broad spectrum antibiotic properties, challenges of mice with Staphylococcus aureus, Klebsiella pneumoniae, or Escherichia coli yielded survivals that were not different from those of wild-type animals. In sum, cathepsin G-/- neutrophils have no obvious defects in function; either cathepsin G is not required for any of these normal neutrophil functions or related azurophil granule proteases with different specificities (ie, neutrophil elastase, proteinase 3, azurocidin, and/or others) can substitute for it in vivo.


Assuntos
Catepsinas/genética , Neutrófilos/fisiologia , Animais , Catepsina G , Quimiotaxia de Leucócito , Deleção de Genes , Homozigoto , Camundongos , Ativação de Neutrófilo/fisiologia , Fagocitose , Serina Endopeptidases/fisiologia
12.
Blood ; 94(9): 3178-84, 1999 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-10556205

RESUMO

To date, the normal transcriptional regulation of the human beta-globin gene cluster has been recapitulated most accurately in transgenic mice that carry large yeast artificial chromosome (YAC) or ligated cosmid constructs. However, these large transgenes still exhibit variegated expression levels, perhaps because they tend to rearrange upon integration, or because the cloning vectors remain attached to the globin inserts. To try to circumvent these potential problems, we investigated the transgenic properties of a 100-kb DNA fragment containing the entire human beta-globin cluster propagated in a bacterial artificial chromosome (BAC). We created 9 independent mouse lines, each carrying 1 to 6 copies of the human beta-globin cluster without the attached BAC vector. Five of the lines carry unrearranged copies of the cluster. Reverse-transcriptase polymerase chain reaction (RT-PCR) analysis of adult F(1) mice showed that 2 lines express human beta globin at levels approximately equivalent to the endogenous mouse beta-major genes. One line expresses no human beta globin, while the remaining 6 lines show intermediate expression levels. Complete gamma-->beta-globin gene switching occurs, but is slightly delayed with respect to the endogenous mouse embryonic-->adult switch. Since these data are similar to what has been obtained using globin YACs or ligated cosmids, we conclude that (1) globin transgenes propagated in BACs are no less likely to rearrange than their cosmid or YAC counterparts, and (2) the retention of YAC vector sequences in a transgene probably has no significant impact on globin expression when using constructs of this size.


Assuntos
Cromossomos Bacterianos , DNA/genética , Técnicas de Transferência de Genes , Vetores Genéticos , Globinas/genética , Animais , Cromossomos Artificiais de Levedura , Humanos , Camundongos , Camundongos Transgênicos , Família Multigênica
13.
Proc Natl Acad Sci U S A ; 96(15): 8627-32, 1999 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-10411926

RESUMO

Dipeptidyl peptidase I (DPPI) is a lysosomal cysteine protease that has been implicated in the processing of granzymes, which are neutral serine proteases exclusively expressed in the granules of activated cytotoxic lymphocytes. In this report, we show that cytotoxic lymphocytes derived from DPPI-/- mice contain normal amounts of granzymes A and B, but these molecules retain their prodipeptide domains and are inactive. Cytotoxic assays with DPPI-/- effector cells reveal severe defects in the induction of target cell apoptosis (as measured by [(125)I]UdR release) at both early and late time points; this defect is comparable to that detected in perforin-/- or granzyme A-/- x B-/- cytotoxic lymphocytes. DPPI therefore plays an essential role in the in vivo processing and activation of granzymes A and B, which are required for cytotoxic lymphocyte granule-mediated apoptosis.


Assuntos
Dipeptidil Peptidases e Tripeptidil Peptidases/metabolismo , Serina Endopeptidases/metabolismo , Linfócitos T Citotóxicos/imunologia , Animais , Apoptose/imunologia , Catepsina C , Grânulos Citoplasmáticos/enzimologia , Grânulos Citoplasmáticos/imunologia , Testes Imunológicos de Citotoxicidade , Desoxiuridina/metabolismo , Dipeptidil Peptidases e Tripeptidil Peptidases/deficiência , Ativação Enzimática , Citometria de Fluxo , Marcação de Genes/métodos , Granzimas , Células Matadoras Ativadas por Linfocina , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/imunologia , Camundongos , Camundongos Knockout , Perforina , Proteínas Citotóxicas Formadoras de Poros , Precursores de Proteínas/metabolismo , Linfócitos T Citotóxicos/enzimologia
14.
Blood ; 93(3): 963-73, 1999 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-9920846

RESUMO

Human granzyme H is a neutral serine protease that is expressed predominantly in the lymphokine-activated killer (LAK)/natural killer (NK) compartment of the immune system. The gene that encodes this granzyme is located between the granzyme B and cathepsin G genes on human chromosome 14q11.2. Although the murine orthologue of human granzyme H has not yet been identified, murine granzymes C, D, E, F, and G also lie between the murine granzyme B and cathepsin G genes on murine chromosome 14; murine granzymes C, D, and F are also highly expressed in LAK cells, but minimally in cytotoxic T lymphocytes (CTL). We therefore tested whether the 5' flanking region of human granzyme H contains the cis-acting DNA sequences necessary to target a reporter gene to the LAK/NK compartment of transgenic mice. A 1.2-kb fragment of 5' flanking human granzyme H sequence was linked to an SV40 large T-antigen (TAg) reporter gene and used to create six transgenic founder lines. SV40 TAg was specifically expressed in the LAK cells of these mice, but not in resting T or NK cells, in CTL, or in any other tissues. Most mice eventually developed a fatal illness characterized by massive hepatosplenomegaly and disseminated organ infiltration by large malignant lymphocytes. Cell lines derived from splenic tumors were TAg+ and NK1.1(+) large granular lymphocytes and displayed variable expression of CD3, CD8, and CD16. Although these cell lines contained perforin and expressed granzymes A, B, C, D, and F, they did not exhibit direct cytotoxicity. Collectively, these results suggest that the 5' flanking sequences of the human granzyme H gene target expression to an NK/T progenitor compartment and to activated NK (LAK) cells. Mice and humans may therefore share a regulatory "program" for the transcription of NK/LAK specific granzyme genes.


Assuntos
Regulação Enzimológica da Expressão Gênica , Genes , Células Matadoras Ativadas por Linfocina/enzimologia , Células Matadoras Naturais/enzimologia , Sequências Reguladoras de Ácido Nucleico , Serina Endopeptidases/genética , Linfócitos T/enzimologia , Animais , Antígenos Transformantes de Poliomavirus/genética , Antígenos Transformantes de Poliomavirus/fisiologia , Cromossomos Humanos Par 14/genética , Indução Enzimática , Feminino , Genes Reporter , Granzimas , Humanos , Células Matadoras Ativadas por Linfocina/patologia , Células Matadoras Naturais/patologia , Transtornos Linfoproliferativos/genética , Transtornos Linfoproliferativos/imunologia , Transtornos Linfoproliferativos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos SCID , Camundongos Transgênicos , Células-Tronco Neoplásicas/metabolismo , Proteínas Recombinantes de Fusão/fisiologia , Serina Endopeptidases/biossíntese , Baço/patologia , Linfócitos T/patologia
15.
Curr Opin Immunol ; 10(5): 581-7, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9794837

RESUMO

CD8+ cytotoxic lymphocytes, natural killer cells and lymphokine-activated killer cells depend primarily on the perforin/granzyme system to kill their targets, while CD4+ T cells utilize Fas and other mechanisms to induce cell death. The molecular mechanisms used by these pathways to induce target cell apoptosis may converge on common death substrates.


Assuntos
Citotoxicidade Imunológica , Linfócitos T Citotóxicos/imunologia , Animais , Apoptose , Linfócitos T CD4-Positivos/imunologia , Granzimas , Humanos , Glicoproteínas de Membrana/fisiologia , Perforina , Proteínas Citotóxicas Formadoras de Poros , Serina Endopeptidases/fisiologia , Receptor fas/fisiologia
16.
J Immunol ; 160(3): 1268-78, 1998 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-9570543

RESUMO

Human CR2 (CD21) is a B lymphocyte protein whose surface expression is restricted primarily to the mature cell stage during development. To study the transcriptional mechanisms that govern cell- and stage-restricted CR2 expression, we first performed transient transfection analysis using constructs extending from -5 kb to +75 bp (-5 kb/+75) in the CR2 promoter. The promoter was found to be broadly active, with no evidence of cell- or stage-specific reporter gene expression. However, the addition of a 2.5-kb intronic gene segment (containing a DNase I hypersensitive site) to the (-5-kb/+75) construct resulted in appropriate reporter gene expression, defined as the silencing of the (-5-kb/+75) promoter activity only in non-CR2-expressing cells. Interestingly, appropriate reporter gene expression required stable transfection of the constructs in cell lines, suggesting nuclear matrix or chromatin interactions may be important for appropriate CR2 gene expression. Importantly, transgenic mice also required the intronic silencer to generate lymphoid tissue-specific reporter gene expression. Some transgenic founder lines did not demonstrate reporter gene expression, however, indicating that additional transcriptional regulatory elements are present in other regions of the CR2 gene. In summary, these data support the hypothesis that human CR2 expression is regulated primarily by an intronic silencer with lineage- and B cell stage-specific activity.


Assuntos
Linfócitos B/metabolismo , Regulação da Expressão Gênica/imunologia , Íntrons/imunologia , Receptores de Complemento 3d/genética , Sequências Reguladoras de Ácido Nucleico/imunologia , Animais , Linfócitos B/imunologia , Sequência de Bases , Sítios de Ligação/genética , Sítios de Ligação/imunologia , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Desoxirribonuclease I/genética , Feminino , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Especificidade de Órgãos/genética , Especificidade de Órgãos/imunologia , RNA Mensageiro/biossíntese , Receptores de Complemento 3d/biossíntese , Transcrição Gênica/imunologia
17.
J Biol Chem ; 273(3): 1629-33, 1998 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-9430705

RESUMO

Granzyme B (GzmB) is a neutral serine protease found in cytotoxic lymphocytes; this enzyme is critically involved in delivering the rapid apoptotic signal to susceptible target cells. GzmB has been difficult to study and has not yet been produced in non-mammalian systems because of the complex processing events that are thought to be required for its activation. In this report, we have successfully produced fully active, soluble recombinant GzmB (rGzmB) in a yeast-based system by fusing GzmB cDNA in frame with yeast alpha-factor cDNA, using the yeast KEX2 signal peptidase to release the processed enzyme into the supernatant of yeast cultures. We expressed the proenzyme form of GzmB as well and determined that pro-GzmB is efficiently converted to its active form by the cysteine proteinase dipeptidyl peptidase I. The fully processed enzyme was able to hydrolyze the synthetic substrate N-t-butyloxycarbonyl-L-alanyl-L-alanyl-L-aspartyl (Boc-Ala-Ala-Asp) thiobenzyl ester with a kcat of 17 s-1 and catalytic efficiency kcat/Km of 181,237 M-1 S-1; the recombinant enzyme is therefore at least twice as active as purified native GzmB. In addition, the recombinant enzyme hydrolyzes Boc-Ala-Ala-Met thiobenzyl ester with a kcat of 3.2 S-1 and a catalytic efficiency kcat/Km of 65,306 M-1 S-1. Purified rGzmB can also cleave the putative substrate caspase-3 into its signature p20/p10 forms. Unlike caspases, rGzmB is not sensitive to inhibition by several peptide-based inhibitors, including Ac-DEVD-CHO, Ac-YVAD-CMK, and ZIETD-FMK, as well as Zn2+ (a known inhibitor of caspase-3). Structural studies of rGzmB may allow us to better understand the substrate specificity of this enzyme and to design better inhibitors.


Assuntos
Serina Endopeptidases/biossíntese , Animais , Cisteína Endopeptidases/metabolismo , Inibidores Enzimáticos/farmacologia , Granzimas , Hexosaminidases/metabolismo , Camundongos , Pichia , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/metabolismo , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Especificidade por Substrato , Células Tumorais Cultivadas , Zinco/farmacologia
18.
Arch Dermatol ; 133(6): 757-60, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9197831

RESUMO

BACKGROUND: Rheumatoid neutrophilic dermatitis (RND) is a recently recognized, rare cutaneous manifestation of rheumatoid arthritis. It occurs in patients with severe rheumatoid arthritis and is typically asymptomatic. Rheumatoid neutrophilic dermatitis was originally described by Ackerman in 1978. Since that time, 8 patients with this disease have been described in the literature. OBSERVATIONS: We report 2 cases of RND. Findings of skin biopsy specimens from both patients revealed characteristic signs of dermal leukocytosis and leukocytoclasia without vasculitis. The pathogenesis of the neutrophilic infiltrate is unclear. Processes that may play a role in the pathogenesis of RND include immune complex activations, cell adhesion and migration, and cytokine release. CONCLUSIONS: Rheumatoid neutrophilic dermatitis falls into the spectrum of neutrophilic vascular reactions described by Jorizzo and Daniels. Although early reports suggest that prominent leukocytoclasia is not a feature of RND, our findings confirm the observations of Lowe et al that leukocytoclasia can be seen in RND and may be striking. It is important for dermatologists to be aware of this rare manifestation of rheumatoid arthritis.


Assuntos
Artrite Reumatoide/complicações , Dermatite/etiologia , Neutrófilos/patologia , Artrite Reumatoide/patologia , Dermatite/patologia , Humanos , Masculino , Pessoa de Meia-Idade
19.
Semin Immunol ; 9(2): 127-33, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9194223

RESUMO

Granzymes are neutral serine proteases that are stored in the specialized lytic granules of cytotoxic lymphocytes. A mutation introduced into the granzyme B locus leads to a severe defect in the ability of cytotoxic lymphocytes to induce apoptosis in susceptible target cells, and reduces the severity of class I-dependent acute graft-versus-host disease (GvHD). However, granzyme B-independent cytotoxicity also exists: in CD8+ cells, most of it is perforin-dependent, but in CD4+ cells, the Fas system and an additional pathway are involved. The identification of these pathways and their physiological relevance may lead to new approaches for inhibiting cytotoxic lymphocyte functions.


Assuntos
Citotoxicidade Imunológica , Serina Endopeptidases/fisiologia , Linfócitos T Citotóxicos/enzimologia , Animais , Caspase 1 , Mapeamento Cromossômico , Cisteína Endopeptidases/metabolismo , Ativação Enzimática , Exocitose , Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Doença Enxerto-Hospedeiro/imunologia , Granzimas , Humanos , Imunidade Celular
20.
J Biol Chem ; 272(16): 10695-703, 1997 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-9099719

RESUMO

Dipeptidyl peptidase I (DPPI) is a lysosomal cysteine protease that catalyzes the sequential removal of dipeptides from the amino termini of various protein substrates. We have isolated a cDNA coding for murine DPPI from mouse thymus and spleen cDNA libraries. The deduced amino acid sequence codes for a protein of 462 amino acid residues; comparison of this deduced sequence with that of rat and human DPPI revealed 90.1% and 77.8% identity, respectively. Using DPPI cDNA, we obtained two BAC (Bacterial Artificial Chromosome) clones that contained the murine DPPI locus. The DPPI gene consists of seven exons and 6 introns, and spans approximately 20 kilobases. Using fluorescence in situ chromosome hybridization, we localized murine DPPI to chromosome 7D3-E1.1. We determined that DPPI protein is widely distributed in mouse tissues, although its relative abundance varies from tissue to tissue. In contrast to previous reports, we show here that DPPI mRNA and protein levels and enzymatic activity are unchanged during in vitro T cell activation, implying that this enzyme is not rate-limiting for granzyme processing.


Assuntos
Mapeamento Cromossômico , Dipeptidil Peptidases e Tripeptidil Peptidases/biossíntese , Dipeptidil Peptidases e Tripeptidil Peptidases/genética , Linfócitos T/enzimologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Catepsina C , Catepsinas/química , Clonagem Molecular , DNA Complementar , Dipeptidil Peptidases e Tripeptidil Peptidases/química , Éxons , Biblioteca Gênica , Humanos , Hibridização in Situ Fluorescente , Íntrons , Cariotipagem , Ativação Linfocitária , Camundongos , Dados de Sequência Molecular , RNA Mensageiro/metabolismo , Ratos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Mapeamento por Restrição , Homologia de Sequência de Aminoácidos , Baço/enzimologia , Linfócitos T/imunologia , Timo/enzimologia
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