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1.
Hum Reprod ; 37(12): 2768-2776, 2022 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-36223599

RESUMEN

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.


Asunto(s)
Histerosalpingografía , Infertilidad , Femenino , Humanos , Embarazo , Tasa de Natalidad , Análisis Costo-Beneficio , Nacimiento Vivo
2.
Dalton Trans ; 45(26): 10771-9, 2016 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-27292266

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-26274114

RESUMEN

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.


Asunto(s)
Acción Capilar , Hidrodinámica , Modelos Teóricos , Agua , Gravitación , Dinámicas no Lineales
4.
Phys Rev E Stat Nonlin Soft Matter Phys ; 84(2 Pt 1): 021701, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21928999

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-19407151

RESUMEN

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.


Asunto(s)
Amelogénesis/fisiología , Catepsina C/metabolismo , Esmalte Dental/enzimología , Calicreínas/metabolismo , Calcificación de Dientes/fisiología , Amelogénesis/genética , Animales , Catepsina C/genética , Esmalte Dental/ultraestructura , Proteínas del Esmalte Dental/genética , Proteínas del Esmalte Dental/metabolismo , Regulación del Desarrollo de la Expresión Génica , Humanos , Calicreínas/genética , Mandíbula , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Ratones Noqueados , Ratones Mutantes , Diente Molar/ultraestructura , Proteínas Recombinantes , Especificidad de la Especie , Calcificación de Dientes/genética
7.
Eur Phys J E Soft Matter ; 26(1-2): 97-101, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18414787

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-16802559

RESUMEN

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.


Asunto(s)
Seguridad , Succión/métodos , Cicatrización de Heridas , Heridas y Lesiones/terapia , Sesgo , Enfermedad Crónica , Medicina Basada en la Evidencia , Estudios de Seguimiento , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Proyectos de Investigación , Tamaño de la Muestra , Trasplante de Piel , Succión/efectos adversos , Resultado del Tratamiento , Vacio
9.
BJOG ; 110(2): 121-7, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12618154

RESUMEN

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.


Asunto(s)
Actitud del Personal de Salud , Actitud Frente a la Salud , Satisfacción del Paciente , Resultado del Embarazo/psicología , Adulto , Estudios de Cohortes , Estudios Transversales , Femenino , Humanos , Masculino , Enfermeras Obstetrices , Paridad , Atención Posnatal , Embarazo
10.
J Biol Chem ; 276(21): 18551-6, 2001 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-11279033

RESUMEN

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.


Asunto(s)
Catepsina C/metabolismo , Mastocitos/enzimología , Serina Endopeptidasas/metabolismo , Animales , Catepsina C/genética , Células Cultivadas , Quimasas , Activación Enzimática/genética , Eliminación de Gen , Regulación Enzimológica de la Expresión Génica , Ratones , Serina Endopeptidasas/genética , Triptasas
11.
Blood ; 94(12): 4282-93, 1999 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-10590073

RESUMEN

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.


Asunto(s)
Catepsinas/genética , Neutrófilos/fisiología , Animales , Catepsina G , Quimiotaxis de Leucocito , Eliminación de Gen , Homocigoto , Ratones , Activación Neutrófila/fisiología , Fagocitosis , Serina Endopeptidasas/fisiología
12.
Blood ; 94(9): 3178-84, 1999 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-10556205

RESUMEN

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.


Asunto(s)
Cromosomas Bacterianos , ADN/genética , Técnicas de Transferencia de Gen , Vectores Genéticos , Globinas/genética , Animales , Cromosomas Artificiales de Levadura , Humanos , Ratones , Ratones Transgénicos , Familia de Multigenes
13.
Proc Natl Acad Sci U S A ; 96(15): 8627-32, 1999 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-10411926

RESUMEN

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.


Asunto(s)
Dipeptidil-Peptidasas y Tripeptidil-Peptidasas/metabolismo , Serina Endopeptidasas/metabolismo , Linfocitos T Citotóxicos/inmunología , Animales , Apoptosis/inmunología , Catepsina C , Gránulos Citoplasmáticos/enzimología , Gránulos Citoplasmáticos/inmunología , Pruebas Inmunológicas de Citotoxicidad , Desoxiuridina/metabolismo , Dipeptidil-Peptidasas y Tripeptidil-Peptidasas/deficiencia , Activación Enzimática , Citometría de Flujo , Marcación de Gen/métodos , Granzimas , Células Asesinas Activadas por Linfocinas , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/inmunología , Ratones , Ratones Noqueados , Perforina , Proteínas Citotóxicas Formadoras de Poros , Precursores de Proteínas/metabolismo , Linfocitos T Citotóxicos/enzimología
14.
Blood ; 93(3): 963-73, 1999 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-9920846

RESUMEN

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.


Asunto(s)
Regulación Enzimológica de la Expresión Génica , Genes , Células Asesinas Activadas por Linfocinas/enzimología , Células Asesinas Naturales/enzimología , Secuencias Reguladoras de Ácidos Nucleicos , Serina Endopeptidasas/genética , Linfocitos T/enzimología , Animales , Antígenos Transformadores de Poliomavirus/genética , Antígenos Transformadores de Poliomavirus/fisiología , Cromosomas Humanos Par 14/genética , Inducción Enzimática , Femenino , Genes Reporteros , Granzimas , Humanos , Células Asesinas Activadas por Linfocinas/patología , Células Asesinas Naturales/patología , Trastornos Linfoproliferativos/genética , Trastornos Linfoproliferativos/inmunología , Trastornos Linfoproliferativos/patología , Masculino , Ratones , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Ratones SCID , Ratones Transgénicos , Células Madre Neoplásicas/metabolismo , Proteínas Recombinantes de Fusión/fisiología , Serina Endopeptidasas/biosíntesis , Bazo/patología , Linfocitos T/patología
15.
Curr Opin Immunol ; 10(5): 581-7, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9794837

RESUMEN

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.


Asunto(s)
Citotoxicidad Inmunológica , Linfocitos T Citotóxicos/inmunología , Animales , Apoptosis , Linfocitos T CD4-Positivos/inmunología , Granzimas , Humanos , Glicoproteínas de Membrana/fisiología , Perforina , Proteínas Citotóxicas Formadoras de Poros , Serina Endopeptidasas/fisiología , Receptor fas/fisiología
16.
J Immunol ; 160(3): 1268-78, 1998 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-9570543

RESUMEN

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.


Asunto(s)
Linfocitos B/metabolismo , Regulación de la Expresión Génica/inmunología , Intrones/inmunología , Receptores de Complemento 3d/genética , Secuencias Reguladoras de Ácidos Nucleicos/inmunología , Animales , Linfocitos B/inmunología , Secuencia de Bases , Sitios de Unión/genética , Sitios de Unión/inmunología , Diferenciación Celular/genética , Diferenciación Celular/inmunología , Desoxirribonucleasa I/genética , Femenino , Humanos , Masculino , Ratones , Ratones Transgénicos , Datos de Secuencia Molecular , Especificidad de Órganos/genética , Especificidad de Órganos/inmunología , ARN Mensajero/biosíntesis , Receptores de Complemento 3d/biosíntesis , Transcripción Genética/inmunología
17.
J Biol Chem ; 273(3): 1629-33, 1998 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-9430705

RESUMEN

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.


Asunto(s)
Serina Endopeptidasas/biosíntesis , Animales , Cisteína Endopeptidasas/metabolismo , Inhibidores Enzimáticos/farmacología , Granzimas , Hexosaminidasas/metabolismo , Ratones , Pichia , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/metabolismo , Serina Endopeptidasas/genética , Serina Endopeptidasas/metabolismo , Especificidad por Sustrato , Células Tumorales Cultivadas , Zinc/farmacología
18.
Arch Dermatol ; 133(6): 757-60, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9197831

RESUMEN

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.


Asunto(s)
Artritis Reumatoide/complicaciones , Dermatitis/etiología , Neutrófilos/patología , Artritis Reumatoide/patología , Dermatitis/patología , Humanos , Masculino , Persona de Mediana Edad
19.
J Biol Chem ; 272(16): 10695-703, 1997 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-9099719

RESUMEN

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.


Asunto(s)
Mapeo Cromosómico , Dipeptidil-Peptidasas y Tripeptidil-Peptidasas/biosíntesis , Dipeptidil-Peptidasas y Tripeptidil-Peptidasas/genética , Linfocitos T/enzimología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Catepsina C , Catepsinas/química , Clonación Molecular , ADN Complementario , Dipeptidil-Peptidasas y Tripeptidil-Peptidasas/química , Exones , Biblioteca de Genes , Humanos , Hibridación Fluorescente in Situ , Intrones , Cariotipificación , Activación de Linfocitos , Ratones , Datos de Secuencia Molecular , ARN Mensajero/metabolismo , Ratas , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Mapeo Restrictivo , Homología de Secuencia de Aminoácido , Bazo/enzimología , Linfocitos T/inmunología , Timo/enzimología
20.
Semin Immunol ; 9(2): 127-33, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9194223

RESUMEN

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.


Asunto(s)
Citotoxicidad Inmunológica , Serina Endopeptidasas/fisiología , Linfocitos T Citotóxicos/enzimología , Animales , Caspasa 1 , Mapeo Cromosómico , Cisteína Endopeptidasas/metabolismo , Activación Enzimática , Exocitosis , Expresión Génica , Regulación Enzimológica de la Expresión Génica , Enfermedad Injerto contra Huésped/inmunología , Granzimas , Humanos , Inmunidad Celular
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