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1.
Clin Microbiol Infect ; 24(7): 749-754, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29208561

RESUMEN

OBJECTIVES: We aimed to study whether ciprofloxacin prophylaxis reduces infectious complications in patients undergoing autologous haematopoietic cell transplantation (AHCT). METHODS: This is a quasi-experimental, retrospective, before-after study. We compared the incidence of bacterial-related complications among 356 patients with multiple myeloma (MM) (n = 202) and lymphoma (n = 154) who underwent AHCT with (n = 177) or without (n = 179) ciprofloxacin prophylaxis between 03/2007 and 10/2012 and between 10/2012 and 07/2016, respectively, at a single centre. RESULTS: Febrile neutropaenia, bacteraemia, and pneumonia were significantly more common among patients who underwent AHCT during the second study period and did not receive antibacterial prophylaxis compared with patients who underwent AHCT during the first study period and received antibacterial prophylaxis (89.9% (161/179) vs. 83.1% (147/177), difference 6.9%, 95% CI 0-14.1%, P = 0.002; 15.1% (27/179) vs. 4.5% (8/177), difference 10.6%, 95% CI 4.4-16.9%, p < 0.0001; 12.3% (22/179) vs. 6.2% (11/177), difference 6.1%, 95% CI 0-12.3%, p = 0.04, respectively). The number-needed-to-treat to prevent one episode of bacteraemia, pneumonia, and febrile neutropaenia was 8.6, 8.5, and 13.7, respectively. Patients with ciprofloxacin prophylaxis had higher rates of ciprofloxacin-resistant bacteraemia (62.5% (5/8) vs. 18.5% (5/27), difference 44%, 95% CI 7-70%, p = 0.01). In multivariate analysis, ciprofloxacin prophylaxis significantly decreased the odds of bacteraemia (OR 0.19, 95% CI 0.07-0.52; p < 0.0001) and pneumonia (OR 0.37, 95% CI 0.16-0.85, p = 0.02). CONCLUSION: According to our single-centre experience, patients with MM and lymphoma undergoing AHCT may benefit from antibacterial prophylaxis with ciprofloxacin.


Asunto(s)
Profilaxis Antibiótica , Ciprofloxacina/uso terapéutico , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Linfoma/cirugía , Mieloma Múltiple/cirugía , Complicaciones Posoperatorias/prevención & control , Trasplante Autólogo/efectos adversos , Adulto , Anciano , Antibacterianos/uso terapéutico , Bacteriemia/etiología , Bacteriemia/microbiología , Bacteriemia/prevención & control , Estudios Controlados Antes y Después , Neutropenia Febril/etiología , Neutropenia Febril/prevención & control , Femenino , Humanos , Israel , Masculino , Persona de Mediana Edad , Neumonía/etiología , Neumonía/microbiología , Neumonía/prevención & control , Complicaciones Posoperatorias/microbiología , Estudios Retrospectivos , Adulto Joven
2.
Oncogene ; 35(11): 1373-85, 2016 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-26096934

RESUMEN

Therapy resistance remains a major problem in estrogen receptor-α (ERα)-positive breast cancer. A subgroup of ERα-positive breast cancer is characterized by mosaic presence of a minor population of ERα-negative cancer cells expressing the basal cytokeratin-5 (CK5). These CK5-positive cells are therapy resistant and have increased tumor-initiating potential. Although a series of reports document induction of the CK5-positive cells by progestins, it is unknown if other 3-ketosteroids share this ability. We now report that glucocorticoids and mineralocorticoids effectively expand the CK5-positive cell population. CK5-positive cells induced by 3-ketosteroids lacked ERα and progesterone receptors, expressed stem cell marker, CD44, and displayed increased clonogenicity in soft agar and broad drug-resistance in vitro and in vivo. Upregulation of CK5-positive cells by 3-ketosteroids required induction of the transcriptional repressor BCL6 based on suppression of BCL6 by two independent BCL6 small hairpin RNAs or by prolactin. Prolactin also suppressed 3-ketosteroid induction of CK5+ cells in T47D xenografts in vivo. Survival analysis with recursive partitioning in node-negative ERα-positive breast cancer using quantitative CK5 and BCL6 mRNA or protein expression data identified patients at high or low risk for tumor recurrence in two independent patient cohorts. The data provide a mechanism by which common pathophysiological or pharmacologic elevations in glucocorticoids or other 3-ketosteroids may adversely affect patients with mixed ERα+/CK5+ breast cancer. The observations further suggest a cooperative diagnostic utility of CK5 and BCL6 expression levels and justify exploring efficacy of inhibitors of BCL6 and 3-ketosteroid receptors for a subset of ERα-positive breast cancers.


Asunto(s)
Neoplasias de la Mama/patología , Proteínas de Unión al ADN/metabolismo , Resistencia a Antineoplásicos/genética , Receptor alfa de Estrógeno/metabolismo , Queratina-5/metabolismo , Aldosterona/farmacología , Animales , Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Proteínas de Unión al ADN/genética , Dexametasona/farmacología , Doxorrubicina/farmacología , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glucocorticoides/farmacología , Humanos , Receptores de Hialuranos/biosíntesis , Células MCF-7 , Ratones , Ratones Desnudos , Mineralocorticoides/farmacología , Recurrencia Local de Neoplasia/genética , Trasplante de Neoplasias , Progestinas/farmacología , Pronóstico , Prolactina/farmacología , Proteínas Proto-Oncogénicas c-bcl-6 , Interferencia de ARN , ARN Interferente Pequeño/genética , Receptores de Progesterona/genética , Tamoxifeno/análogos & derivados , Tamoxifeno/farmacología , Trasplante Heterólogo , Regulación hacia Arriba
3.
Environ Model Softw ; 65: 30-40, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26109906

RESUMEN

System dynamics (SD) is an effective approach for helping reveal the temporal behavior of complex systems. Although there have been recent developments in expanding SD to include systems' spatial dependencies, most applications have been restricted to the simulation of diffusion processes; this is especially true for models on structural change (e.g. LULC modeling). To address this shortcoming, a Python program is proposed to tightly couple SD software to a Geographic Information System (GIS). The approach provides the required capacities for handling bidirectional and synchronized interactions of operations between SD and GIS. In order to illustrate the concept and the techniques proposed for simulating structural changes, a fictitious environment called Daisyworld has been recreated in a spatial system dynamics (SSD) environment. The comparison of spatial and non-spatial simulations emphasizes the importance of considering spatio-temporal feedbacks. Finally, practical applications of structural change models in agriculture and disaster management are proposed.

4.
Phys Chem Chem Phys ; 16(32): 17183-95, 2014 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-25012908

RESUMEN

Three CuO/CeO2 catalyst with different morphologies of ceria, namely nanospheres, nanorods and nanocubes, were synthesized and used to catalyze the water-gas shift (WGS) reaction. The reactivity tests showed that the Cu supported on the ceria nanospheres exhibited both the highest activity and superior stability when compared with the nanocube and nanorod ceria catalysts. Operando X-ray diffraction (XRD), X-ray absorption fine structure (XAFS) and diffuse reflectance Fourier transform infrared spectroscopy (DRIFTS) methods were used to characterize these catalysts in their working state. High resolution electron microscopy (HRTEM, STEM) was used to look at the local atomic structure and nano-scale morphology. Our results show that the morphology of the ceria support, which can involve different crystal faces and concentrations of defects and imperfections, has a critical impact on the catalytic properties and influences: (1) the dispersion of CuO in the as-synthesized catalyst; (2) the particle size of metallic Cu upon reduction during the WGS reaction, (3) the stability of the metallic Cu upon variations of temperature, and (4) the dissociation of water on the ceria support. The nanosphere ceria catalyst showed an excellent water dissociation capability, the best dispersion of Cu and a strong Cu-Ce interaction, therefore delivering the best performance among the three WGS catalysts. The metallic Cu, which is the active species during the WGS reaction, was more stabilized on the nanospheres than on the nanorods and nanocubes and thus led to a better stability of the nanosphere catalyst than the other two architectures. Each catalyst exhibited a distinctive line-shape in the 800-1600 cm(-1) region of the DRIFTS spectra, pointing to the existence of different types of carbonate or carboxylate species as surface intermediates for the WGS.

5.
Clin Exp Obstet Gynecol ; 41(2): 219-22, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24779258

RESUMEN

OBJECTIVE: This report describes a successful surgical approach to multiple in vitro fertilization (IVF) failures in the setting of hydrosalpinges, which had been previously treated with Essure inserts. MATERIALS AND METHODS: A non-smoking 33-year-old Caucasian G2 P0020 (body mass index: BMI = 22) attended for second opinion. Her history was significant for bilateral hydrosalpinges having been noted on hysterosalpingogram two years earlier. This was managed by hysteroscopic placement of Essure inserts bilaterally. One year later, and now with Essure in situ, the patient completed three IVF cycles elsewhere. Her first and third IVF attempts resulted in biochemical pregnancy, while human chorionic gonadotropin (hCG) was negative after the second cycle. Upon presentation at the authors' center and before beginning a fourth IVF cycle, further testing and surgical removal of the Essure devices was recommended. RESULTS: Repeat hysteroscopy was unremarkable; laparoscopic bilateral salpingectomy and extirpation of Essure implants was accomplished without difficulty. Following menses, the patient initiated IVF with three embryos transferred. At day 60, a single intrauterine pregnancy was identified with positive cardiac activity (rate > 100/min). Her obstetrical course was uneventful; a healthy 4,195 gram male infant was delivered (breech) by Cesarean at 40 weeks' gestation. CONCLUSION: Essure inserts comprise inner fibers of polyethylene terephthalate, a stainless steel coil, and a nickel-titanium coil. The product received FDA approval as a contraceptive in 2002 although its use for hydrosalpinx remains off-label. While successful outcomes with IVF following Essure placement have been reported, this is the first description of pregnancy and delivery from IVF after Essure removal. Essure may be considered for sterilization when laparoscopy is contraindicated, but experience with its use specifically for treating hydrosalpinges before IVF is limited. This observed association between prior poor IVF outcomes and Essure with subsequent delivery after surgical Essure removal is the first of its kind to be reported, and warrants further investigation.


Asunto(s)
Remoción de Dispositivos , Enfermedades de las Trompas Uterinas/cirugía , Fertilización In Vitro , Resultado del Embarazo , Esterilización Tubaria/instrumentación , Adulto , Transferencia de Embrión , Femenino , Humanos , Recién Nacido , Laparoscopía , Masculino , Embarazo
6.
Oncogene ; 33(17): 2215-24, 2014 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-23708665

RESUMEN

Prolactin controls the development and function of milk-producing breast epithelia but also supports growth and differentiation of breast cancer, especially luminal subtypes. A principal signaling mediator of prolactin, Stat5, promotes cellular differentiation of breast cancer cells in vitro, and loss of active Stat5 in tumors is associated with antiestrogen therapy failure in patients. In luminal breast cancer, progesterone induces a cytokeratin-5 (CK5)-positive basal cell-like population. This population possesses characteristics of tumor stem cells including quiescence, therapy resistance and tumor-initiating capacity. Here we report that prolactin counteracts induction of the CK5-positive population by the synthetic progestin (Pg) R5020 in luminal breast cancer cells both in vitro and in vivo. CK5-positive cells were chemoresistant as determined by fourfold reduced rate of apoptosis following docetaxel exposure. Pg-induction of CK5 was preceded by marked upregulation of BCL6, an oncogene and transcriptional repressor critical for the maintenance of leukemia-initiating cells. Knockdown of BCL6 prevented induction of CK5-positive cell population by Pg. Prolactin suppressed Pg-induced BCL6 through Jak2-Stat5 but not Erk- or Akt-dependent pathways. In premenopausal but not postmenopausal patients with hormone receptor-positive breast cancer, tumor protein levels of CK5 correlated positively with BCL6, and high BCL6 or CK5 protein levels were associated with unfavorable clinical outcome. Suppression of Pg-induction of CK5-positive cells represents a novel prodifferentiation effect of prolactin in breast cancer. The present progress may have direct implications for breast cancer progression and therapy as loss of prolactin receptor-Stat5 signaling occurs frequently and BCL6 inhibitors currently being evaluated for lymphomas may have value for breast cancer.


Asunto(s)
Neoplasias de la Mama/metabolismo , Proteínas de Unión al ADN/metabolismo , Regulación Neoplásica de la Expresión Génica , Queratina-5/metabolismo , Prolactina/fisiología , Animales , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Línea Celular Tumoral , Proteínas de Unión al ADN/genética , Femenino , Expresión Génica , Humanos , Queratina-5/genética , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Neoplasias Hormono-Dependientes/metabolismo , Neoplasias Hormono-Dependientes/mortalidad , Neoplasias Hormono-Dependientes/patología , Premenopausia , Progesterona/fisiología , Congéneres de la Progesterona/farmacología , Promegestona/farmacología , Proteínas Proto-Oncogénicas c-bcl-6 , Receptores de Estrógenos/metabolismo , Factor de Transcripción STAT5/metabolismo
7.
Scand J Immunol ; 78(2): 157-66, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23679844

RESUMEN

Sjögren's syndrome (SjS), an autoimmune disease characterized by exocrine gland dysfunction leading to dry mouth and dry eye diseases, is typified by progressive leucocyte infiltrations of the salivary and lacrimal glands. Histologically, these leucocyte infiltrations generally establish periductal aggregates, referred to as lymphocytic foci (LF), which occasionally appear as germinal centre (GC)-like structures. The formation and organization of these LF suggest an important and dynamic role for helper T cells (TH), specifically TH1, TH2 and the recently discovered TH17, in development and onset of clinical SjS, considered a B cell-mediated hypersensitivity type 2 disease. Despite an ever-increasing focus on identifying the underlying aetiology of SjS, defining factors that initiate this autoimmune disease remain a mystery. Thus, determining interactions between infiltrating TH cells and exocrine gland tissue (auto-)antigens represents a fertile research endeavour. This review discusses pathological functions of TH cells in SjS, the current status of TH cell receptor gene rearrangements associated with human and mouse models of SjS and potential future prospects for identifying receptor-autoantigen interactions.


Asunto(s)
Autoantígenos/inmunología , Glándulas Exocrinas/inmunología , Receptores de Antígenos de Linfocitos T/inmunología , Síndrome de Sjögren/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Animales , Autoantígenos/genética , Linfocitos B/inmunología , Linfocitos B/patología , Quimiotaxis de Leucocito/inmunología , Citocinas/biosíntesis , Citocinas/inmunología , Glándulas Exocrinas/patología , Expresión Génica , Humanos , Ratones , Receptores de Antígenos de Linfocitos T/clasificación , Receptores de Antígenos de Linfocitos T/genética , Transducción de Señal , Síndrome de Sjögren/genética , Síndrome de Sjögren/patología , Linfocitos T Colaboradores-Inductores/clasificación , Linfocitos T Colaboradores-Inductores/patología
8.
J Dent Res ; 92(5): 444-9, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23533183

RESUMEN

In Sjögren's Syndrome (SS), inherent glandular defects, autoimmunity, and mononuclear cell infiltration within the salivary glands cause reduced salivation leading to xerostomia. Excessive production of type I interferons (IFN), triggered by environmental and genetic factors, is considered pathogenic in this disorder. However, whether type I IFN production is causative or an outcome of the disease process is not known. To address this question, we introduced a deficiency of interferon alpha receptor 1 (Ifnar1) into B6.Aec1Aec2 mice, which are known to have the genetic loci necessary for developing a SS-like disorder. This new mouse strain, B6.Aec1Aec2Ifnar1 (-/-), lacking type I IFN-mediated signaling, was characterized for pilocarpine-induced salivation, the presence of serum autoantibodies, sialoadenitis, and dacryoadenitis. Compared with the B6.Aec1Aec2Ifnar1 (+/+) (wild-type) mice, the B6.Aec1Aec2Ifnar1 (-/-) (knockout) mice had significantly lower mononuclear cell infiltration in the salivary and lacrimal glands. The knockout mice were completely protected from salivary gland dysfunction. Surprisingly, they had a robust autoantibody response comparable with that of the wild-type mice. These findings demonstrate that, in the absence of type I IFN-mediated signaling, systemic autoantibody responses can be dissociated from glandular pathology. Our study suggests that, in genetically susceptible individuals, the type I IFN pathway can instigate certain features of SS.


Asunto(s)
Receptor de Interferón alfa y beta/metabolismo , Salivación/fisiología , Sialadenitis/inmunología , Síndrome de Sjögren/inmunología , Animales , Autoanticuerpos/sangre , Dacriocistitis/genética , Dacriocistitis/inmunología , Dacriocistitis/metabolismo , Modelos Animales de Enfermedad , Femenino , Predisposición Genética a la Enfermedad , Ratones , Ratones Endogámicos , Ratones Noqueados , Receptor de Interferón alfa y beta/deficiencia , Receptor de Interferón alfa y beta/genética , Salivación/genética , Salivación/inmunología , Sialadenitis/genética , Sialadenitis/metabolismo , Transducción de Señal/genética , Síndrome de Sjögren/genética , Síndrome de Sjögren/metabolismo , Síndrome de Sjögren/fisiopatología
9.
Scand J Immunol ; 76(3): 237-45, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22703193

RESUMEN

Sjögren's syndrome (SS) of humans and SS-like (SjS-like) diseases in mouse models are characterized by chronic immune attacks against the salivary and lacrimal glands leading to exocrine dysfunction. One characteristic of SS and SjS-like diseases repeatedly observed is a strong upregulated expression of both the type I (α/ß) and type II (γ) interferons (IFNs). In addition, recent global transcriptome studies have identified a variety of IFN-stimulated gene (ISG) transcripts differentially expressed in tissues of SS patients and mouse models exhibiting SjS-like disease. Analyses of these transcriptome databases indicate that the sets of differentially expressed genes are highly restricted, suggesting that there is a unique specificity in ISGs activated (or suppressed) during development and onset of disease. As a result, these observations have led to both SS and SjS-like diseases being designated as 'interferon-signature' diseases. While SS and SjS-like diseases may be designated as such, very little effort has been made to determine what an interferon-signature might signify relative to autoinflammation and whether it might point directly to an underlying etiopathological mechanism. Here, we review these limited data and provide a model of how the products of these genes interact molecularly and biologically to define critical details of SS pathology.


Asunto(s)
Autoinmunidad/genética , Interferones/genética , Síndrome de Sjögren/genética , Transcriptoma/genética , Animales , Autoinmunidad/inmunología , Perfilación de la Expresión Génica , Humanos , Interferones/inmunología , Ratones , Síndrome de Sjögren/inmunología , Transcriptoma/inmunología
10.
Climacteric ; 14(1): 49-53, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20450412

RESUMEN

OBJECTIVE: A considerable number of postmenopausal women who receive estrogen therapy are also treated for hypercholesterolemia with cholesterol-lowering statins. Statins and steroid hormones can compete for the same steroid-metabolizing enzymes. We investigated whether long-term administration of statins had an effect on serum estrogen and androgen levels in postmenopausal women receiving and not receiving oral estrogen therapy. METHODS: A subgroup analysis from the Estrogen in the Prevention of Atherosclerosis Trial, a randomized, double-blind, placebo-controlled trial, was performed. A total of 222 women were randomized to receive either placebo or 1 mg of oral micronized 17ß-estradiol daily for 2 years. In both the placebo and treatment groups, participants with low density lipoprotein cholesterol levels >160 mg/dl were treated with statins. Blood samples were obtained at baseline and every 6 months during the trial. Serum levels of dehydroepiandrosterone, androstenedione, testosterone, estrone and 17ß-estradiol were measured by radioimmunoassay. RESULTS: Among 86 placebo- and 90 estradiol-treated subjects with baseline and on-trial hormone measurements, no significant differences were observed between the statin-free and statin-treated groups in mean changes from baseline to on-trial levels in any of the androgens or estrogens, whether or not the postmenopausal women were treated with estrogen. CONCLUSION: The results suggest that estrogen therapy and statins can be used simultaneously with no deleterious effects on circulating hormone levels.


Asunto(s)
Estradiol/uso terapéutico , Estrógenos/uso terapéutico , Hormonas Esteroides Gonadales/sangre , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , LDL-Colesterol/sangre , Método Doble Ciego , Femenino , Humanos , Persona de Mediana Edad , Posmenopausia
11.
Scand J Immunol ; 73(1): 18-28, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21128999

RESUMEN

Production of autoantibodies is one of the main features of primary Sjögren's syndrome (pSS). Long-lived plasma cells (PC) can produce autoantibodies for prolonged period of times without being affected by immunosuppressive therapies. As of today, little is known about the long-lived PC subset and their contribution to autoimmunity. We have characterized the phenotypic and migratory properties of peripheral blood PC isolated from pSS patients (grouped by focus score, FS) and compared them to PC from rheumatoid arthritis (RA) patients and normal non-autoimmune subjects. We observed two populations of PC in all study groups, CD19+ PC and CD19- PC. Interestingly, the CD19- PC subset was most prominent in autoimmune patients (pSS and RA) compared to normal controls. Further investigation of the PC phenotype revealed that a high percentage of both CD19+ and CD19- PC isolated from pSS and RA patients did not express the CD27 marker, which is normally highly expressed on all types of PC. Differences in the expression of markers such as IgM, IgG, CD95 and CXCR3 in the group with high FS compared to FS = 1, underscore the heterogeneity of pSS patient group and demonstrate that phenotypic pattern of circulating PC associates with the severity of inflammation in the salivary glands of these patients. Our migration experiments show that addition of CXCL12 to PC in vitro, do not alter the migration potential of PC in any group tested. However, we observed an overall higher spontaneous migration of PC from pSS compared to both RA and normal controls.


Asunto(s)
Artritis Reumatoide/inmunología , Autoanticuerpos/sangre , Células Plasmáticas/inmunología , Síndrome de Sjögren/inmunología , ADP-Ribosil Ciclasa 1/sangre , Antígenos CD19/sangre , Artritis Reumatoide/sangre , Movimiento Celular/inmunología , Femenino , Citometría de Flujo , Humanos , Masculino , Persona de Mediana Edad , Receptores CXCR3/sangre , Receptores CXCR4/sangre , Síndrome de Sjögren/sangre , Sindecano-1/sangre
13.
Scand J Immunol ; 64(3): 295-307, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16918699

RESUMEN

Sjögren's syndrome (SjS) is a systemic autoimmune disease in which an immunological attack primarily against the salivary and lacrimal glands results in loss of acinar cell tissue and function leading to stomatitis sicca and keratoconjunctivitis sicca. In recent years, the NOD mouse has become an accepted model of SjS, exhibiting a spontaneously developing disease that strongly mimics the human condition. Two genetic regions, one on chromosome 1 (designated Aec2) and the second on chromosome 3 (designated Aec1) of NOD mice, have been shown to be necessary and sufficient to recapitulate SjS-like disease in non-susceptible C57BL/6 mice. Here we describe a newly derived strain, C57BL/6.NOD-Aec1R1Aec2, in which a recombination in Aec1 has resulted in reducing this genetic region to less than 20 cM from 48.5 cM. Profiling of this recombinant inbred strain has revealed that male mice maintain a full SjS-like disease, whereas female mice exhibit stomatitis sicca in the absence of detectable keratoconjunctivitis sicca. These data suggest SjS-like disease in the NOD mouse shows gender-specific regulation determined by autosomal genes.


Asunto(s)
Intercambio Genético , Modelos Animales de Enfermedad , Queratoconjuntivitis Seca/genética , Caracteres Sexuales , Síndrome de Sjögren/genética , Animales , Anticuerpos Antinucleares/sangre , Dacriocistitis/patología , Femenino , Queratoconjuntivitis Seca/patología , Aparato Lagrimal/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos NOD/genética , Ratones Endogámicos , Ratones Transgénicos , Sialadenitis/patología , Glándula Submandibular/patología
14.
Kidney Int ; 69(4): 691-8, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16518326

RESUMEN

The primary goal of this study was to test the hypothesis that Oxalobacter colonization alters colonic oxalate transport thereby reducing urinary oxalate excretion. In addition, we examined the effects of intraluminal calcium on Oxalobacter colonization and tested the hypothesis that endogenously derived colonic oxalate could be degraded by lyophilized Oxalobacter enzymes targeted to this segment of the alimentary tract. Oxalate fluxes were measured across short-circuited, in vitro preparations of proximal and distal colon removed from Sprague-Dawley rats and placed in Ussing chambers. For these studies, rats were colonized with Oxalobacter either artificially or naturally, and urinary oxalate, creatinine and calcium excretions were determined. Colonized rats placed on various dietary treatment regimens were used to evaluate the impact of calcium on Oxalobacter colonization and whether exogenous or endogenous oxalate influenced colonization. Hyperoxaluric rats with some degree of renal insufficiency were also used to determine the effects of administering encapsulated Oxalobacter lysate on colonic oxalate transport and urinary oxalate excretion. We conclude that in addition to its intraluminal oxalate-degrading capacity, Oxalobacter interacts physiologically with colonic mucosa by inducing enteric oxalate secretion/excretion leading to reduced urinary excretion. Whether Oxalobacter, or products of Oxalobacter, can therapeutically reduce urinary oxalate excretion and influence stone disease warrants further investigation in long-term studies in various patient populations.


Asunto(s)
Mucosa Intestinal/metabolismo , Oxalatos/metabolismo , Oxalatos/orina , Oxalobacter formigenes/fisiología , Animales , Transporte Biológico , Calcio/sangre , Calcio/fisiología , Calcio/orina , Colon/metabolismo , Colon/microbiología , Creatinina/sangre , Creatinina/orina , Mucosa Intestinal/microbiología , Intestinos/microbiología , Masculino , Nefrectomía , Oxalatos/sangre , Probióticos/uso terapéutico , Ratas , Ratas Sprague-Dawley , Insuficiencia Renal/metabolismo , Insuficiencia Renal/fisiopatología , Cálculos Urinarios/prevención & control
15.
Scand J Immunol ; 60(6): 552-65, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15584966

RESUMEN

Sjogren's syndrome-like autoimmune exocrinopathy (AEC) in the nonobese diabetic (NOD) mouse progresses from a preimmune phase to an immune phase, resulting in dry mouth and/or dry eyes. In the present study, the impact of the prototypical T-helper type 1 cytokine, interferon-gamma (IFN-gamma), on the onset of AEC was investigated using both the IFN-gamma and the IFN-gamma receptor gene knockout mice, NOD.IFN-gamma(-/-) and NOD.IFN-gammaR(-/-), respectively. Neither the NOD.IFN-gamma(-/-) nor the NOD.IFN-gammaR(-/-) mice exhibited increased acinar cell apoptosis and abnormal salivary protein expression, typically observed in parental NOD mice prior to disease. Without these preimmune phase abnormalities, NOD.IFN-gamma(-/-) and NOD.IFN-gammaR(-/-) mice showed no subsequent autoimmune responses against the salivary glands at 20 weeks. Interestingly, real-time polymerase chain reaction and electrophoretic gel mobility shift assays suggested that IFN-gamma and STAT1, as well as the transcriptional activity of STAT1 in NOD glands, were increased at birth. Unlike the neonatal submandibular glands of NOD or NOD-scid mice that show abnormal glandular morphogenesis at birth, the submandibular glands of the newly constructed congenic strain, NOD-scid.IFN-gamma(-/-), were found to be normal. Taken together, IFN-gamma appears to play a critical role not only during the later immune phase of AEC, but also the early preimmune phase, independent of effector functions of immune cells. How exactly IFN-gamma functions during this period remains speculative.


Asunto(s)
Expresión Génica/fisiología , Interferón gamma/metabolismo , Síndrome de Sjögren/metabolismo , Animales , Células CHO , Cricetinae , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Técnica del Anticuerpo Fluorescente , Interferón gamma/genética , Interferón gamma/inmunología , Metaloproteinasas de la Matriz/metabolismo , Ratones , Ratones Endogámicos NOD , Factor de Transcripción STAT1 , Proteínas y Péptidos Salivales/metabolismo , Síndrome de Sjögren/etiología , Síndrome de Sjögren/inmunología , Glándula Submandibular/metabolismo , Transactivadores/genética , Transactivadores/metabolismo
16.
Crit Rev Oral Biol Med ; 13(1): 5-16, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12097234

RESUMEN

Sjögren's Syndrome (SS) is a chronic autoimmune disease characterized by histological and functional alterations of salivary and lacrimal glands that result in a severe dryness of the mouth and the eyes. The etiology of SS has remained undefined despite investigators' significant efforts to identify the mechanisms of initiation. Based on histopathology, several animal models are available--such as MRL/lpr, NZW/NZB, NFS/sld, graft vs. host, transgenic mouse expressing viral surface antigen, and the non-obese diabetic (NOD) mouse--for investigation of the etiology of SS. Biochemical and immunological similarities between human SS and autoimmune exocrinopathy (AEC) in the NOD mouse, including the loss of secretory function, establish the NOD mouse as an appropriate model to unravel the underlying pathophysiology of SS. Recently, several NOD congenic partner strains have been developed to investigate the roles of genetic intervals, cytokines, and autoantibodies in the disease pathogenesis. Studies on NOD-scid suggest that the pathogenesis of SS occurs in two phases: an asymptomatic phase, in which epithelial cells of exocrine tissues undergo dedifferentiation accompanied by elevated apoptosis; and a second phase in which autoaggression is mounted against target organ autoantigens, resulting in the activation of T- and B-cells, and the generation of autoantibodies. The presence of autoantibodies on the cell-surface signaling receptor, the muscarinic(3) receptor, in both SS patients and the NOD mice correlates with the hallmark clinical symptom of secretory dysfunction. Additionally, the NOD mouse model provides an important example of how both Th1 and Th2 cytokines, as well as non-immune genetic loci, are involved in the maintenance of and progression to the overt disease state. Ultimately, analysis of these data provides insight into potentially novel therapeutic interventions.


Asunto(s)
Autoinmunidad/fisiología , Glándulas Exocrinas/inmunología , Ratones Endogámicos NOD , Síndrome de Sjögren/inmunología , Animales , Apoptosis , Autoinmunidad/genética , Modelos Animales de Enfermedad , Glándulas Exocrinas/fisiopatología , Humanos , Activación de Linfocitos , Ratones , Receptor Muscarínico M3/inmunología , Síndrome de Sjögren/genética
17.
Ann N Y Acad Sci ; 958: 59-68, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12021084

RESUMEN

Recent successes in treating type 1 diabetic patients with islet transplantation portends a future need for an increase in available islets. Ductal structures of the adult pancreas contain multipotent stem cells that, under the proper in vitro conditions, can both self-renew and differentiate into functional islets of Langerhans. In vitro-generated islets exhibit temporal changes in mRNA transcripts for islet-associated markers as well as regulated insulin responses following glucose challenge. When implanted into diabetic mice, in vitro-generated islets induce neovascularization and reverse insulin-dependent diabetes. The possibility of growing functional endocrine pancreas from stem cells provides new opportunities to produce large numbers of islets, even autologous islets, for use as implants.


Asunto(s)
Diferenciación Celular , Diabetes Mellitus Tipo 1/cirugía , Trasplante de Islotes Pancreáticos/métodos , Islotes Pancreáticos/citología , Células Madre/citología , Animales , Técnicas de Cultivo de Célula/métodos , Diabetes Mellitus Tipo 1/patología , Desarrollo Embrionario y Fetal , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Insulina/metabolismo , Islotes Pancreáticos/efectos de los fármacos , Ratones , Niacinamida/farmacología , Somatostatina/metabolismo
20.
J Urol ; 166(4): 1487-91, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11547118

RESUMEN

PURPOSE: The gut inhabiting bacterium Oxalobacter formigenes may be a negative risk factor in recurrent calcium oxalate kidney stone disease that apparently maintains oxalic acid homeostasis in its host via the degradation of dietary oxalate. The possibility of using this bacterium as probiotic treatment to reduce urinary oxalate was investigated in a rat model. MATERIALS AND METHODS: Male Sprague-Dawley rats were placed on a diet supplemented with ammonium oxalate to induce a state of severe hyperoxaluria. Subgroups of these rats received an esophageal gavage of 1 x 10(3), 10(5), 10(7) or 10(9) O. formigenes per feeding for a 2-week period. Each rat was followed for general health and changes in urinary oxalate. RESULTS: Rats with chronic hyperoxaluria resulting from high dietary oxalate that were treated with O. formigenes showed decreased urinary oxalate within 2 days of initiating probiotic supplementation. The amount of the decrease in a 2-week period proved directly proportional to the dose of bacteria. Urinary oxalate in rats receiving higher amounts of O. formigenes returned to almost normal. Throughout the study the rats remained healthy with no signs of toxicity, antibody development or a histopathological condition. CONCLUSIONS: Probiotic treatment of hyperoxaluric rats with O. formigenes may significantly and rapidly reduce the level of oxalate in the urine. This probiotic treatment appears to be safe and well tolerated. The approach may be feasible for treating calcium oxalate kidney stone disease.


Asunto(s)
Hiperoxaluria/terapia , Oxalobacter formigenes , Probióticos/uso terapéutico , Animales , Hiperoxaluria/microbiología , Masculino , Ratas , Ratas Sprague-Dawley , Factores de Tiempo
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