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1.
Benef Microbes ; 13(1): 13-23, 2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-34895109

RESUMEN

Acute upper respiratory tract infections (URTIs) are caused by numerous viruses and bacteria. URTIs can be a cause of morbidity and are among the most common reasons for visiting healthcare practitioners and prescribing antibiotics to children in addition to causing absenteeism from school and work. Oral intake of Lacticaseibacillus rhamnosus GG DSM 33156 has shown beneficial health effects in several clinical trials, primarily relating to immune function and gastrointestinal health in children and adults. It has also been suggested that oral intake of L. rhamnosus GG DSM 33156 can reduce the incidence rate and alleviate symptoms of URTIs in children. We here report the results of a randomised, double-blind, placebo-controlled trial of 619 children aged 2-6 years conducted at a single centre in Scotland. The children, who were in day care or primary school, were followed over a 16-week intervention period with 309 randomised in the active group and 310 in the placebo group. The parents or guardians reported a daily healthcare status and any presumed episodes of URTI, which were subsequently confirmed by a general practitioner. The investigational product was well tolerated in the trial. Although a general trend towards a beneficial effect was observed, this trial did not demonstrate that L. rhamnosus GG DSM 33156 significantly reduced the incidence of URTIs, diagnosed by a general practitioner according to prespecified criteria (primary endpoint). Moreover, none of the secondary efficacy endpoints were met. Applying a Ward's hierarchical clustering, two separate clusters, focussing on four quality of life-related endpoints, were identified. Cluster 1 was associated with more severe URTI characteristics than cluster 2. Cluster 2 was significantly enriched with children who consumed the product, indicating that the symptoms children experience during an URTI are alleviated by the intake of L. rhamnosus GG DSM 33156. The study is registered at ClinicalTrials.gov ID: NCT03636191.


Asunto(s)
Lacticaseibacillus rhamnosus , Probióticos , Infecciones del Sistema Respiratorio , Adulto , Niño , Preescolar , Método Doble Ciego , Humanos , Probióticos/uso terapéutico , Calidad de Vida , Sistema Respiratorio , Infecciones del Sistema Respiratorio/tratamiento farmacológico
2.
Clin Hemorheol Microcirc ; 69(1-2): 69-75, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29630539

RESUMEN

BACKGROUND: Renal transplant patients have a higher risk for malignancies of the renal transplant. In most cases suspected renal malignancies will be detected during the regular ultrasound follow-up and will require cross-sectional imaging to rule out a malignant aetiology. But it is well known that contrast agents for computed tomography or magnetic resonance imaging are critical in patients with limited renal function. OBJECTIVE: This study aims to compare the sensitivity and specificity of contrast-enhanced ultrasound (CEUS) and gold standard imaging modalities in characterizing suspected renal transplant malignancies in renal transplant patients. METHODS: A total of 22 renal transplant patients who underwent one or more CEUS examinations and at least one standard imaging modality (CT or MRI) between 2005 and 2017 were included. Patient ages ranged from 28.2 years to 74.6 (mean age 55.7 years; SD±13.0 years). CEUS of 22 patients was correlated with a standard imaging modality, CT (15 out of 22) or MRI (7 out of 22), serving as gold standard. RESULTS: CEUS showed a sensitivity of 100%, a specificity of 94.4%, a positive predictive value (PPV) of 80%, and a negative predictive value (NPV) of 100%. CONCLUSIONS: CEUS is an eligible method to help characterizing suspected renal malignancies in renal transplant patients compared to the well-established imaging modalities CT and MRI. As an imaging modality with no nephrotoxic effects CEUS can be used repeatedly even in patients with limited renal function.


Asunto(s)
Medios de Contraste/uso terapéutico , Neoplasias Renales/diagnóstico por imagen , Trasplante de Riñón/efectos adversos , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada por Rayos X/métodos , Ultrasonografía/métodos , Adulto , Anciano , Femenino , Humanos , Neoplasias Renales/patología , Masculino , Persona de Mediana Edad
3.
Clin Hemorheol Microcirc ; 69(1-2): 77-82, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29630540

RESUMEN

BACKGROUND: Despite of the more potent immunosuppressive medication, vascular rejection is still a major issue after renal transplantation. Renal biopsy is the gold standard diagnostic to evaluate acute and chronic allograft rejection. As it is an invasive diagnostic there is the risk of complications like haematoma, arteriovenous fistulas, active bleeding or infection. Contrast-enhanced ultrasound is a non-invasive imaging modality that allows visualising renal transplant perfusion. OBJECTIVE: To analyse the sensitivity and specificity of contrast-enhanced ultrasound (CEUS) compared to biopsy as gold standard in diagnosing vascular rejection in renal transplant patients. METHODS: A total of 57 renal transplant recipients with poor renal allograft function with initial diagnostic imaging between 2006 and 2017 were included in the study. Clinical data and imaging studies were analysed retrospectively. The diagnostic accuracy of CEUS in diagnosing vascular rejection of the renal transplant was compared to renal biopsy as gold standard. Out of 57 patients 7 patients showed signs of vascular rejection in biopsy. In 6 out of these 7 patients CEUS described irregularities in renal perfusion suspicious of vascular rejection. RESULTS: CEUS showed a sensitivity of 85.7%, a specificity of 100%, a positive predictive value (PPV) of 100%, and a negative predictive value (NPV) of 98.0%. CONCLUSIONS: CEUS is a safe, non-nephrotoxic imaging modality for the initial imaging of renal transplant recipients with elevated kidney function parameters suspicious of vascular rejection. Compared to renal biopsy as gold standard CEUS shows a high specificity and PPV in detecting signs of vascular rejection. Since sub-types of vascular rejection with cellular and humoral components with greater risk for allograft loss have been described renal biopsy is inevitable in these cases.


Asunto(s)
Medios de Contraste/uso terapéutico , Rechazo de Injerto/diagnóstico por imagen , Trasplante de Riñón/efectos adversos , Riñón/patología , Ultrasonografía/métodos , Adulto , Anciano , Femenino , Humanos , Trasplante de Riñón/métodos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
4.
Clin Hemorheol Microcirc ; 67(3-4): 407-413, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28885208

RESUMEN

BACKGROUND: Vascular complications in renal transplant patients are a well-known issue in post transplant patient care. If malfunctioning of the renal transplant is suspected to be caused by vascular complications an early diagnosis and therapy is required to maintain the renal transplant. Computed tomography (CT), digital substraction angiography (DSA) and radioisotope renography are the gold standard imaging modalities to diagnose vascular complications. OBJECTIVE: To analyse the sensitivity and specificity of contrast-enhanced ultrasound (CEUS) in comparison to the standard imaging modalities CT, DSA and radioisotope renography in the diagnosis of vascular complications in renal transplant patients. METHODS: A total of 33 renal transplant recipients with elevated kidney function parameters with initial diagnostic imaging between 2006 and 2017 were included in the study. The imaging studies and clinical data were analysed retrospectively. The diagnostic accuracy of CEUS was compared to CT, DSA and renal scintigraphy respectively which are classified as gold standard for diagnosis of vascular complications in renal transplant patients. Out of 23 patients 15 patients showed vascular complications in CT, DSA or radioisotope renography and in 15 out of 15 patients CEUS detected the vascular complication. RESULTS: CEUS showed a sensitivity of 100%, a specificity of 66.7%, a positive predictive value (PPV) of 71.4%, and a negative predictive value (NPV) of 100%. CONCLUSIONS: CEUS is a non-nephrotoxic and safe method for the initial imaging of vascular complications in renal transplant recipients. Compared to the gold standard imaging modalities CT, DSA and radioisotope renography CEUS shows a high sensitivity and NPV in detecting vascular complications. In cases with suspected stenosis of the transplant renal artery additional DSA might be needed.


Asunto(s)
Medios de Contraste/uso terapéutico , Trasplante de Riñón/efectos adversos , Riñón/patología , Ultrasonografía/métodos , Adulto , Anciano , Femenino , Humanos , Trasplante de Riñón/métodos , Masculino , Persona de Mediana Edad , Adulto Joven
5.
J Eur Acad Dermatol Venereol ; 31(7): 1161-1167, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28107559

RESUMEN

BACKGROUND: Cytosolic phospholipase A2 (cPLA2α) is an enzyme suggested as a therapeutic target in inflammatory skin diseases. AVX001, a cPLA2α inhibitor, was investigated in a randomized, double-blind, placebo-controlled, split-design, first-in-man study in patients with mild to moderate psoriasis. OBJECTIVES: The primary objective was to evaluate cutaneous safety and tolerability of AVX001 in doses from 0.002% to 5.0%. Safety was assessed as local skin reaction adverse events (LSRAE) grades 3-4. The secondary objective was assessment of efficacy on modified PASI (mPASI) score compared with placebo. METHODS: Of 94 randomized men, 88 completed treatment with AVX001 and placebo. The treatment period was four weeks with two-week follow-up with assessment at screening, randomization and once weekly until study end. AVX001 and placebo were applied blinded at symmetrically affected areas once daily. RESULTS: AVX001 was safe with no grades 3-4 LSRAE. A 29% reduction in mPASI was seen at the 5% dose level at week four. Post hoc analysis of combined doses of 3% and 5% showed a clinical relevant effect with 31% reduction in mPASI (P = 0.058) and statically significant reduction of the infiltration (P = 0.036). The actively treated side showed improvement in mPASI score after one week of treatment, and the observed improvement continued throughout the four weeks of treatment. CONCLUSIONS: Treatment with AVX001 is well tolerated in doses up to 5%, and showed placebo-adjusted, clinical effects at a level of statistical significance. The improvement throughout the treatment period suggests that longer treatment could conceivably result in superior efficacy.


Asunto(s)
Ácidos Grasos Omega-3/uso terapéutico , Inhibidores de Fosfolipasa A2/uso terapéutico , Psoriasis/tratamiento farmacológico , Administración Tópica , Adulto , Anciano , Estudios de Cohortes , Citosol/enzimología , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Ácidos Grasos Omega-3/administración & dosificación , Ácidos Grasos Omega-3/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Inhibidores de Fosfolipasa A2/administración & dosificación , Inhibidores de Fosfolipasa A2/efectos adversos , Placebos , Índice de Severidad de la Enfermedad
6.
Transplant Proc ; 45(7): 2795-7, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24034052

RESUMEN

Headaches are one of the most common medical complaints. The differentiation of benign primary headaches from the small number of patients with secondary headaches may be challenging, but failure to recognize a serious headache can be fatal. We report the case of a 49-year-old renal transplant patient, who was admitted to hospital because of intractable right-sided headaches. Cerebral imaging was unremarkable. Not until 2 days later did the patient develop a rash of grouped vesicles located in the right dermatome C3. Consecutively cerebrospinal fluid tested positive for Varizella zoster virus (VZV), indicating VZV meningitis. Therapy was started with intravenous acyclovir with rapid improvement. Here in we have described an atypical case of VZV reactivation in a renal transplant patient, who initially presented with headaches without any skin manifestation. Because of their compromised immune system, transplant patients have a high risk for visceral involvement of VZV infections, which are a life-threatening emergency. Therefore, vaccination of seronegative patients should be part of the pretransplant workup. Accurate and fast diagnosis of infection is essential to immediately start antiviral therapy.


Asunto(s)
Cefalea/etiología , Trasplante de Riñón/efectos adversos , Meningitis Viral/fisiopatología , Femenino , Herpesvirus Humano 3/aislamiento & purificación , Humanos , Meningitis Viral/virología , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa
7.
Am J Transplant ; 7(12): 2683-92, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17924994

RESUMEN

Programmed death-1 (PD-1) is a recently identified coinhibitory molecule that belongs to the CD28 superfamily. PD-1 has two ligands PD-L1 and PD-L2. There is some evidence that PD-L1 and PD-L2 serve distinct functions, but their exact function in alloimmunity remains unclear. In the present study, we used a GVHD-like model that allows detailed analyses of T-cell activation at a single cell level in vivo to examine the role of PD-1/PD-L1 and PD-1/PD-L2 interactions in regulating proliferation of CD4(+) and CD8(+) T cells in response to alloantigen stimulation. We found that both CD4(+) and CD8(+) T cells proliferated vigorously in vivo and that PD-L1 and PD-L2 exhibit strikingly different effect on T-cell proliferation. While blocking PD-L1 did not affect the in vivo proliferation of CD4(+) and CD8(+) T cells regardless of CD28 costimulation, blocking PD-L2 resulted in a marked increase in the responder frequency of CD8(+) T-cells in vivo. The effect of PD-L2 on the CD8(+) T-cell proliferation is regulated by CD28 costimulation and by the CD4(+) T cells. We conclude that PD-L1 and PD-L2 function differently in regulating alloreactive T-cell activation in vivo, and PD-L2 is predominant in this model in limiting alloreactive CD8(+) T-cell proliferation.


Asunto(s)
Antígeno B7-1/metabolismo , Linfocitos T CD4-Positivos/patología , Linfocitos T CD8-positivos/patología , Enfermedad Injerto contra Huésped/metabolismo , Enfermedad Injerto contra Huésped/patología , Glicoproteínas de Membrana/metabolismo , Péptidos/metabolismo , Animales , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/farmacología , Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Antígeno B7-1/inmunología , Antígeno B7-H1 , Antígenos CD28/metabolismo , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD8-positivos/metabolismo , Proliferación Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Enfermedad Injerto contra Huésped/inmunología , Isoantígenos/inmunología , Isoantígenos/farmacología , Glicoproteínas de Membrana/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Ratones Noqueados , Péptidos/inmunología , Proteína 2 Ligando de Muerte Celular Programada 1 , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología
8.
Am J Transplant ; 7(8): 1917-26, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17617854

RESUMEN

CD28 costimulatory blockade induces tolerance in most murine transplant models but fails to do so in stringent transplant models, such as skin transplantation. The precise immunological mechanisms of CD28-independent rejection remain to be fully defined. Using two novel mouse strains in which both CD28 and either CD4 or CD8 are knocked out (CD4(-/-)CD28(-/-) or CD8(-/-)CD28(-/-) mice), we examined mechanisms of CD28-independent CD4(+) or CD8(+) T-cell-mediated allograft rejection. CD4(-/-)CD28(-/-) and CD8(-/-)CD28(-/) deficient mice rejected fully allogeneic skin allografts at a tempo comparable with that in wild-type mice. Rejection proceeded despite significant reduction in alloreactive T-cell clone sizes suggesting the presence of a subset of T cells harnessing alternate CD28-independent costimulatory pathways. Blockade of CD40-CD154 and CD134-CD134L, but not ICOS-B7h pathways in combination significantly prolonged allograft survival in CD8(-/-)CD28(-/-) recipients and to a lesser extent in CD4(-/-)CD28(-/-) recipients. Prolongation in allograft survival was associated with reduced effector-memory T-cell generation, decreased allospecific Th1 cytokine generation and diminished alloreactive T-cell proliferation in vivo. In aggregate, the data identify these two pathways as critical mediators of CD28-independent rejection by CD4(+) and to a lesser extent CD8(+) T cells, and provide novel mechanistic insights into functions of novel T-cell co-stimulatory pathways in vivo.


Asunto(s)
Antígenos CD28/inmunología , Rechazo de Injerto/inmunología , Trasplante de Piel/inmunología , Animales , Apoptosis , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD4-Positivos/patología , Ligando de CD40/antagonistas & inhibidores , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Linfocitos T CD8-positivos/patología , Proliferación Celular , Modelos Animales de Enfermedad , Rechazo de Injerto/patología , Rechazo de Injerto/prevención & control , Supervivencia de Injerto/inmunología , Inmunidad Celular , Interferón gamma/metabolismo , Interleucina-4/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Ligando OX40/antagonistas & inhibidores , Pronóstico , Trasplante de Piel/patología , Trasplante Homólogo
9.
Kidney Int ; 70(9): 1649-55, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16955106

RESUMEN

Until now, it remains unclear whether the addition of manual daytime exchanges or increasing the nightly dialysate flow is the best strategy to optimize automated peritoneal dialysis (APD) treatment. In this open-label randomized controlled crossover trial, 18 patients with high-average (HA) or low-average (LA) peritoneal transport rates sequentially underwent two different APD regimens for 7 days each, with an intermittent washout period of 7 days. 'Manual exchange' treatment was a conventional APD with low nightly dialysate flow and one manual daytime exchange. 'High-flow' treatment was defined by cycler therapy with high dialysate flow but without manual daytime exchange. Creatinine clearances (8.56+/-1.22 vs 7.87+/-1.04 l/treatment, P = 0.011) and urea nitrogen clearances (12.83+/-1.98 vs 11.68+/-1.06 l/treatment, P = 0.014) were significantly increased during 'high-flow' treatment compared to 'manual exchange' treatment. Sodium removal was significantly lower and glucose absorption was higher with the 'high-flow' regimen. Phosphate clearances, beta2-microglobulin clearances, ultrafiltration, and peritoneal protein loss were not different between the two treatment modalities. Subgroup analysis dependent on peritoneal transport types showed that the effect on clearances was most marked and significant in HA transporters, whereas sodium removal was lowest in LA transporters. We conclude that small solute clearances can be significantly improved and middle molecule clearances maintained in APD patients by increasing the nightly dialysate flow instead of adding a manual daytime exchange. However, the possible benefit of better clearances with higher nightly treatment volumes has to be weighed against increased costs and the possible negative impact of impaired sodium removal, especially in LA transporters.


Asunto(s)
Diálisis Peritoneal/instrumentación , Diálisis Peritoneal/métodos , Insuficiencia Renal/terapia , Adulto , Anciano , Automatización , Costos y Análisis de Costo , Estudios Cruzados , Soluciones para Diálisis/farmacocinética , Determinación de Punto Final , Femenino , Glucanos/farmacocinética , Glucosa/farmacocinética , Humanos , Icodextrina , Masculino , Persona de Mediana Edad , Diálisis Peritoneal/efectos adversos , Diálisis Peritoneal/economía , Insuficiencia Renal/metabolismo , Sodio/metabolismo , Factores de Tiempo , Resultado del Tratamiento
10.
Urol Res ; 29(5): 330-7, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11762795

RESUMEN

Tumor cells, including renal cell carcinoma (RCC) cells, do not effectively stimulate T lymphocyte responses against specific antigens presented on their surface. Reasons for this low immunogenicity may include low or absent expression of MHC class I and/or class II molecules, as well as accessory and costimulatory molecules. We used tumor cell pretreatment with cytokines, together with monoclonal antibodies (mAbs) directed at receptors for costimulatory molecules, to render RCC cells immunostimulatory. Interferon-gamma or tumor necrosis factor-alpha pretreatment enhanced expression of MHC class I and class II molecules, as well as CD54, but had only minimal effects on T cell activation. A CD28 mAb, or an even more effective combination of CD28 and CD5 mAb, induced strong primary proliferative responses of allogeneic resting T lymphocytes. Cytokine pretreatment further augmented this T cell response in vitro and allowed T cell expansion and establishment of T cell lines. Stimulation of T cells with autologous RCC cells resulted in a similar T cell activation but with the expansion of cytolytic T cells directed at autologous MHC class II molecules. These experiments demonstrate that cytokines combined with costimulatory mAbs are useful for increasing the immunogenicity of tumor cells. They also indicate. however, that autologous MHC class II expression on tumor cells, together with strong costimulation, may lead to the activation of autoreactive T cells.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Antígenos CD28/inmunología , Antígenos CD5/inmunología , Carcinoma de Células Renales/inmunología , Inmunización , Neoplasias Renales/inmunología , Humanos , Interferón gamma/farmacología , Activación de Linfocitos/inmunología , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Linfocitos T Citotóxicos/inmunología , Células Tumorales Cultivadas/efectos de los fármacos , Células Tumorales Cultivadas/fisiología , Factor de Necrosis Tumoral alfa/farmacología
11.
Kidney Int Suppl ; (72): S67-70, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10560809

RESUMEN

BACKGROUND: Acute renal failure (ARF) in critically ill patients is mostly part of a multi-organ failure. Therefore, the effects of renal replacement therapy on the liver are clinically important. We investigated the effects of ultrafiltrates of patients treated with continuous venovenous hemofiltration (CVVH) on liver cells in vitro. METHODS: Patients with ARF were consecutively treated with CVVH using Multiflow60 (group I) or FH66 filters (group II). They were comparable with respect to diagnosis, age, sex, laboratory parameters, and renal replacement treatment, but were different in daily diuresis, serum levels, and blood flow. Ultrafiltrates were collected within the first 10 minutes after change of hemofilter. Proliferation (bromodeoxyuridine), vitality (lactate dehydrogenase), and acute-phase protein secretion of HepG2 cells were measured. RESULTS: Ultrafiltrates changed liver cell function significantly compared with medium control. Proliferation (group I 29.8+/-5.2% vs. group II 48.4+/-6.6%, P < 0.05) and vitality (group I 78.7+/-2.0% vs. group II 87.6+/-1.7%, P < 0.01) of HepG2 cells were significantly different. On the one hand, the secretion of the negative acute-phase protein transferrin [group 13.1+/-0.2 (ng/microg protein) vs. group II 5.1+/-0.5 (ng/microg protein), P < 0.01] was significantly reduced by Multiflow60 ultrafiltrates. On the other hand, positive acute-phase protein alpha1-acid glycoprotein was significantly stimulated by Multiflow60 ultrafiltrates [group I 2.6+/-0.1 (ng/microg protein) vs. group II 1.7+/-0.1 (ng/microg protein), P < 0.001]. CONCLUSION: This study demonstrates hepatoactive mediators in the ultrafiltrates. They are hepatotoxic and influence acute-phase protein metabolism. Further studies have to elucidate the different effects in both groups and the analysis of the putative mediator(s). It remains a challenging task to consider therapeutic measures to optimize renal replacement therapy in critically ill patients.


Asunto(s)
Lesión Renal Aguda/terapia , Hemofiltración/métodos , Hígado/citología , Hígado/metabolismo , Proteínas de Fase Aguda/metabolismo , Anciano , Bromodesoxiuridina/farmacocinética , Enfermedad Crítica , Hemofiltración/efectos adversos , Humanos , L-Lactato Deshidrogenasa/metabolismo , Hígado/efectos de los fármacos , Persona de Mediana Edad , Transferrina/metabolismo , Células Tumorales Cultivadas , Ultrafiltración
12.
J Mol Med (Berl) ; 74(1): 43-9, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8834769

RESUMEN

One aim of the genetic modification of tumor cells is the generation of immunogenic variants that can be used for the induction of immune responses against tumors. We engineered the human colorectal carcinoma cell line SW480 by means of plasmid transfection to secrete interleukin (IL)-2. Transfection of SW480 cells resulted in stable IL-2 secretion at 5-30 ng/ml per 10(5) cells in 24 h and, unexpectedly, in CD54 expression on the cell surface. SW480 variants expressing IL-2 and CD54 were tested for their capacity to induce T lymphocyte activation in vitro in comparison to untransfected and CD54 transfected cells. The cytolytic effector function of a class I MHC restricted CD8+, peptide antigen specific T cell clone was augmented following expression of CD54. IL-2 secreting SW480 variants did not further increase antigen-dependent cytolysis. Primary activation of resting T lymphocytes was assessed following allogeneic stimulation. When compared with unmodified SW480 cells, CD54 expressing variants did not initiate T cell proliferation. In contrast, IL-2 secreting SW480 cells strongly promoted primary T cell proliferation. Similarly, exogenous IL-2 and SW480 cells induced T cell proliferation which was not only due to IL-2 but was dependent on tumor cells. However, following the initial wave of cell growth in response to IL-2 secreting SW480 cells T lymphocytes could not be restimulated with SW480 or IL-2 secreting variants and could not be further expanded. T cells initially activated by IL-2 secreting SW480 cells exhibited cytolytic activity towards SW480 cells. This reactivity, however, was transient and completely blocked by K562 cells, suggesting MHC-unrestricted, nonspecific cytotoxicity. We conclude that endogenous IL-2 secretion by the colorectal carcinoma cell line SW480 does not result in the activation of MHC restricted specific T lymphocytes but predominantly induces lymphokine-activated killer cells. Considering that tumor cell vaccines are aimed at inducing tumor-specific immune responses, our in vitro observation would rather argue against the in vivo application of such a tumor cell modification in colorectal cancer.


Asunto(s)
Carcinoma/inmunología , Neoplasias Colorrectales/inmunología , Interleucina-2/inmunología , Secuencia de Aminoácidos , Carcinoma/patología , Neoplasias Colorrectales/patología , Técnica del Anticuerpo Fluorescente Indirecta , Humanos , Interleucina-2/genética , Interleucina-2/metabolismo , Datos de Secuencia Molecular , Linfocitos T/inmunología , Transfección , Células Tumorales Cultivadas
13.
Eur J Cancer ; 31A(13-14): 2396-402, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8652275

RESUMEN

The capacity of colorectal carcinoma and melanoma cell lines to induce primary versus effector T lymphocyte activation in vitro was investigated. Established epithelial tumour cell lines derived from colorectal carcinoma and melanoma did not activate a primary proliferative response of resting T lymphocytes in allogeneic mixed lymphocyte tumour cell cultures (MLTCs). In contrast, the same tumour cells were effectively lysed by preactivated cytolytic T cell clones. This demonstrates that tumour cells are impaired in inducing a primary immune response but are susceptible to effector immune responses. Attempts at improving primary T cell activation revealed that exogenous cytokines, including interferon-gamma (IFN-gamma), tumour necrosis factor-alpha (TNF-alpha) and interleukin-2 (IL-2), were not effective. Expression of CD80 (B7.1), by transfecting a CD80 cDNA into the melanoma cell line SkMel63, improved T cell proliferation considerably. In contrast, CD80 expression in two colorectal carcinoma cell lines (SW480, SW707) did not result in T cell activation. This was not due to lack of class II MHC expression on SW480 since coexpression of a HLA-DR3 alloantigen and CD80 had no effect. Our data suggest that de novo CD80 expression is not, in general, sufficient to improve primary T cell activation by human tumour cells.


Asunto(s)
Antígeno B7-1/fisiología , Neoplasias Colorrectales/inmunología , Activación de Linfocitos , Melanoma/inmunología , Linfocitos T/inmunología , Antígenos de Neoplasias/análisis , Antígeno B7-1/genética , Neoplasias Colorrectales/genética , Citocinas/fisiología , Técnicas de Transferencia de Gen , Genes , Antígeno HLA-DR3/genética , Antígeno HLA-DR3/fisiología , Humanos , Prueba de Cultivo Mixto de Linfocitos , Melanoma/genética , Células Tumorales Cultivadas/inmunología
14.
Cytokines Mol Ther ; 1(3): 211-21, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9384677

RESUMEN

Human tumor cell lines derived from breast and ovarian carcinomas have been found to be ineffective in stimulating the induction phase of an immune response such as T cell proliferation in allogeneic mixed tumor cell lymphocyte cultures. Since representative tumor cell lines are effectively lysed by activated T lymphocytes, the induction of an effector phase is not impaired. In order to reconstitute the potential to induce primary T cell activation, we transfected CD80 into a breast (KS) and an ovarian carcinoma (GG) cell line. CD80 expression in KS cells resulted in improved primary T cell activation, whereas it was ineffective in the case of GG cells. However, treatment of CD80-transfected GG cells with INF-gamma rendered them immunogenic, and resulted in T cell proliferation. Likewise, TNF-alpha and/or INF-gamma augmented T cell proliferation induced by CD80-transfected KS cells. Furthermore, T lymphocytes stimulated with cytokine-treated CD80+ KS cells gave rise to a long term proliferating CD8+ CTL line with class I MHC restricted cytolytic antitumor activity. These studies emphasize the requirement for costimulation in generating tumor-specific immunity, and demonstrate the efficacy of CD80 in generating CD8+ cytolytic T lymphocytes.


Asunto(s)
Antígeno B7-1/fisiología , Neoplasias de la Mama/inmunología , Linfocitos T CD8-positivos/inmunología , Citotoxicidad Inmunológica , Neoplasias Ováricas/inmunología , Linfocitos T/inmunología , Antígenos CD/biosíntesis , Antígeno B7-1/biosíntesis , Células Cultivadas , Técnicas de Cocultivo , Femenino , Citometría de Flujo , Humanos , Interferón gamma/biosíntesis , Interferón gamma/fisiología , Activación de Linfocitos , Proteínas Recombinantes/biosíntesis , Transfección , Células Tumorales Cultivadas
15.
Chirurg ; 52(11): 728-31, 1981 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-7307688

RESUMEN

Since 1977, the Ender and Simon-Weidner nailing technique has been increasingly used at the Surgical University Clinic in Tübingen. This is an simple, gentle, low-risk procedure for surgical stabilization of pertrochanter femoral fractures and fractures of the lateral femoral neck in elderly people. Errors in external rotation are not always avoidable with this procedure, but they are tolerated with a lower surgical mortality than in the more complex method of osteosynthesis. Intraoperative complications are caused by faulty positioning, bad reposition of the fracture, false selection of the pinning site and nail length as well as insufficient splaying of the nails in the femoral head. Postoperative complications occur with distal as well as cranial displacement of the nails. Further complications are caused by placing a normal burden on the fracture too quickly and by the necessity of changing nails. Instructions will be given as to how these errors can be avoided.


Asunto(s)
Fracturas del Fémur/cirugía , Fracturas del Cuello Femoral/cirugía , Fijación Intramedular de Fracturas/métodos , Complicaciones Posoperatorias/prevención & control , Anciano , Humanos , Complicaciones Intraoperatorias/prevención & control , Infección de la Herida Quirúrgica/prevención & control
16.
Zentralbl Allg Pathol ; 122(6): 528-37, 1978.
Artículo en Alemán | MEDLINE | ID: mdl-735491

RESUMEN

Folic acid is given intravenously to rats 5 to 10 days after a dichromate induced damage of the kidneys. These injection cause an additional damage in the function and structure of the kidneys, but on the other hand, they induce a cell proliferation detected by the increased uptake of thymidine. This cell proliferation in the kidney-tissue seems to be a part of specific reactions to the folic acid.


Asunto(s)
División Celular/efectos de los fármacos , Ácido Fólico/farmacología , Enfermedades Renales/patología , Animales , Autorradiografía , Riñón/efectos de los fármacos , Enfermedades Renales/inducido químicamente , Masculino , Dicromato de Potasio , Ratas
17.
Z Klin Chem Klin Biochem ; 13(7): 311-8, 1975 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1189532

RESUMEN

16 Patients with acute right-sided cardiac failure associated with a high pressure of the central venous system, exhibited a marked increase in glutamate dehydrogenase activity in serum. This increase was 40-fold higher than in patients with acute viral hepatitis. Histological examination of seven deceased patients revealed central necrosis within the liver lobule. This observation led us to determine glutamate dehydrogenase activity in microdissected peripheral and central portions from the unchanged liver lobule. A 1.7-fold higher glutamate dehydrogenase activity was found in the central part of the liver lobule than in the peripheral portion. The diagnostic significance of the glutamate dehydrogenase activity distribution along the cords of liver cells is discussed in view of liver diseases with central necrosis.


Asunto(s)
Glutamato Deshidrogenasa/análisis , Hepatopatías/enzimología , Hígado/enzimología , Necrosis/enzimología , Anciano , Alanina Transaminasa/sangre , Aspartato Aminotransferasas/sangre , Pruebas Enzimáticas Clínicas , Femenino , Glutamato Deshidrogenasa/sangre , Insuficiencia Cardíaca/complicaciones , Hepatitis A/enzimología , Hepatomegalia , Humanos , Hepatopatías/diagnóstico , Hepatopatías/patología , Pruebas de Función Hepática , Masculino , Persona de Mediana Edad , Edema Pulmonar/complicaciones
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