Helicobacter pylori inactivation and virulence gene damage using a supported sensitiser for photodynamic therapy.

About half of the world's population is currently infected with Helicobacter pylori, which is involved in the development of several gastro-duodenal pathologies. The increasing number of antibiotic resistance reduces the effectiveness of the first-line therapy, so new strategies to improve the H. pylori eradication rates are needed. Antimicrobial Photodynamic Therapy (APDT) benefits from photogenerated reactive oxygen species, such as singlet oxygen, which inactivate microorganisms by means of photosensitising dyes and visible light. Therefore, it could be a suitable alternative for H. pylori eradication in the gastro-duodenal tract, particularly in patients infected with antibiotic resistant strains. We evaluated APDT against H. pylori, in vitro, using a new photosensitising material (PSM) based on a ruthenium(II) complex covalently bound to micrometric glass beads. Five H. pylori isolates (classified according to cagA genotype, and metronidazole-clarithromycin resistance) were used. Bacteria were mixed with the PSM and incubated in the dark or illuminated by blue light. Aliquots (min 1', 2', 5', 15' and 30') were cultured and colonies were counted after 2-3 days. A 99.99999% decrease was detected in the number of colonies in the irradiated wells where the bacterium was mixed with the PSM, compared to non-illuminated wells or with irradiated wells without PSM. It was also confirmed that DNA is a molecular target for oxidant species released during APDT (evaluated by alkaline gel electrophoresis after endonuclease III incubation, ureC and cagA RT-PCR, and bacterial fingerprint). Results were independent of cagA gene and antibiotic resistances.

Persistent hepatitis C virus (HCV) infection impairs HCV-specific cytotoxic T cell reactivity through Mcl-1/Bim imbalance due to CD127 down-regulation.

In persistent hepatitis C virus (HCV) infection, HCV-specific cytotoxic T lymphocyte (CTL) reactivity is impaired and this affects HCV control. Interleukin-7 receptor (CD127) expression on these cells could regulate CTL reactivity through Mcl-1/Bim balance modulation. Bim is a pro-apoptotic molecule blocked by the action of Mcl-1. Mcl-1/Bim expression and T cell reactivity on HCV-specific CTLs were compared according to CD127 phenotype. Peripheral blood lymphocytes (PBL) from HLA-A2(+) HCV(+) patients were obtained. HCV-specific CTLs were visualized by staining PBL with anti-CD8 and HLA-A2/peptide pentameric complexes (pentamer). Mcl-1/Bim/CD127 phenotype of HCV-specific CTLs was tested by staining detectable CD8(+)/pentamer(+) cells with anti-Mcl-1/Bim/CD127 antibodies. HCV-specific CTL proliferation ability after specific in vitro challenge was tested in the presence and absence of pancaspase inhibitor z-VAD-fmk. All stained cells were analysed by flow cytometry. CD127(low)-expressing HCV-specific CTLs associated with high HCV viraemia, while CD127(high) correlated with undetectable viral loads (P < 0.001). Directly ex vivo, pentamer(+) cell frequency was similar according to CD127 expression level. Nevertheless, CD127(low) pentamer(+) cell proliferation after specific in vitro challenge was impaired (P < 0.05), although this was corrected by z-VAD-fmk treatment (P < 0.05). Mcl-1 expression was low directly ex vivo (P < 0.01), and Bim was up-regulated after antigen encounter (P < 0.05) of CD127(low) pentamer(+) cells. The ex vivo difference between Mcl-1 and Bim expression on pentamer(+) cells correlated positively with CD127 expression level (P < 0.001) and with pentamer(+) cell reactivity (P < 0.05). In summary, a low ex vivo Mcl-1 expression and Bim up-regulation after antigen encounter are involved in CD127(low) HCV-specific CTL hyporeactivity during chronic infection, but it can be overcome by apoptosis blockade.

H. pylori and mitochondrial changes in epithelial cells. The role of oxidative stress

Infection with H. pylori plays a role in the pathogenesis of gastritis,peptic ulcer, gastric carcinoma, and gastric lymphoma, butmechanisms leading to the various clinical manifestations remainobscure and are the primary focus of research in this field.Proliferation and apoptosis are essential in the maintenance ofgastric tissue homeostasis, and changes seen in their balance maycondition gastric mucosal changes during infection. Thus, excessiveapoptosis or proliferation inhibition will result in cell massloss, which is observed in gastric ulcers. On the other hand, acceleratedepithelial cell turnover is characteristic of carcinogenic mucosas.There is also scientific evidence that demonstrates an associationbetween H. pylori infection and exacerbated synthesis offree radicals, the latter being well known as a primary cause of celldeath.A thorough review of the literature and the results of our experimentalresearch lead to conclude that H. pylori-induced oxidativestress activates the intrinsic pathway of apoptosis. Structuraland functional changes caused by this process on mitochondrialorganelles lie at the origin of gastric mucosal toxicity, and lead tothe development of the various manifestations associated with thisinfection. Based on these data we suggest that therapy with antioxidantsshould prove beneficial for the clinical management ofpatients with H. pylori infection(AU)

Regulación de la expresión del co-receptor CCR5 en sujetos con virus de la inmunodeficiencia humana / Expression regulation of CCR5 co-receptor in human immunodeficiency virus subjects

Objetivos Estudiar la expresión diferencial del co-receptor CCR5, en superficie e intracelularmente, en T4 y T8 de pacientes VIH frente a controles. Evaluar causas y mecanismos de regulación de esa expresión en sujetos VIH. Pacientes Se analizaron muestras de 11 controles y 14 de VIH en terapia antirretroviral. Resultados La expresión de superficie del CCR5 en T4 y T8 depacientes VIH disminuyó un 38 y 53% respectivamentefr ente a controles, observándose diferencias estadísticamente significativas. El CCR5 intracelular en T8 fue similar al de controles, sinembargo, en T4 de VIH la proteína intracelular fue más abundante y, como consecuencia, la cantidad total de CCR5 similar a la total de controles. Conclusiones Existe una regulación diferencial en la expresión del CCR5 en T4 y T8 de VIH en relación a controles. En ambas subpoblaciones, la expresión de superficie se halla disminuida, hecho que parece responder a razones diferentes: en T4 se produce internalización de CCR5 quizá como consecuencia de ser arrastrado al interior celular en el proceso de infección por el virus, pero su expresión global es similar a la de controles, en T8 en cambio, no hay internalización sino regulación negativa del receptor en superficie, probablemente consecuencia de la sobreexpresión de interleuquinas ligando del co-receptor que se observaen estos pacientes. Son necesarios estudios que evalúen y expliquen el diferente comportamiento de estas subpoblaciones en la regulación del CCR5 para ampliar el conocimiento sobre la fisiopatología de la enfermedad y facilitar la elección de terapias más efectivas y menos agresiva

Objectives To study the differential expression of CCR5 co-receptor, in surface and intracellularly, in T4 and T8 cells of HIV patients respect to controls. To evaluate causes and mechanisms of that expression regulation in HIV subjects. Patients II controls and 14 HN patients with antirretroviral therapy were studied. Results CCR5 surface expression of HN, both in T4 and in T8, was diminished 38 and 53% respectively respect to controls with significant differences. CCR5 intracellular in T8 was similar to controls, never the less, the intracellular protein in T4 was more abundant and as a consequence, the total amount of CCR5 was similar to the total (surface+intracellular)in controls. Conclusions It exists a diferential regulation in the expression of CCR5 in T4 and T8 of HIV regard to controls. In both subpopulations, the surface expression is diminished,lact that seems to respond to different reasons: In T4 was produced a CCR5 internalization, perhaps as aresult 01 being dragged to the citosol in the virus infection process, but its global expression was similar to controls. However, in T8 there was not internalization but negative regulation of surface receptor, probably due to the sobreexpression of interleukins binding of the co-receptor, what is characteristic in these patients. They are necessary studies that evaluate and explain the different behavior of these subpopulations in the CCR5 regulation to extend the knowledge on the physiopathology of the disease and to facilitate the election of more effective and less aggressive therapies

[Utility of "breath test" in diagnosis of digestive diseases]. / Aplicabilidad de las "pruebas de aliento" al diagnóstico de patología digestiva.

The "breath test" based on the measurement of gases in expired air are an alternative to the study of metabolic and functional alterations in gastroenterology. They are classified into two groups based on the molecule analyzed and if the substrate is isotopically labelled or not: H2 and/or CH4 test (malabsorption of sugars, bacterial overgrowth, etc.) and 13CO2 test (infection by H. pylori, exocrine pancreatic function, etc.).

Aplicabilidad de las «pruebas de aliento» al diagnóstico de patología digestiva / Utility of «breath test» in diagnosis of digestive diseases

Las «pruebas de aliento» basadas en la medida de gases en aire espirado son una alternativa al estudio de alteraciones metabólicas y funcionales en gastroenterología. Se clasifican en dos grupos en función de la molécula analizada y de si el sustrato está o no marcado isotópicamente: prueba de H2 y/o CH4 (malabsorción de azúcares, sobrecrecimiento bacteriano, etc.) y prueba de 13CO2 (infección por H. pylori, función pancreática exocrina, etc.) (AU)

The «breath test» based on the measurement of gases in expired air are an alternative to the study of metabolic and functional alterations in gastroenterology. They are classified into two groups based on the molecule analyzed and if the substrate is isotopically labelled or not: H2 and/or CH4 test (malabsorption of sugars, bacterial overgrowth, etc.) and 13CO2 test (infection by H. pylori, exocrine pancreatic function, etc.) (AU)

Flow cytometric analysis of the in situ hybridization of cyclooxygenase isoforms in mesangial cells treated with cyclosporine A.

BACKGROUND: Cyclosporine A increases oxidative stress in kidney and we hypothesized that cyclooxygenase (COX) may be involved in this effect. MATERIAL AND METHODS: Mesangial cells of Cyclosporine A-treated (4, 7 or 10 days) rats were obtained to evaluate mRNA expression of COX-isoforms (COX-1, constitutive and COX-2, inducible) by "in situ" hybridization. Probes were labelled using "Gene Image Random Prime Labelling Protocol" and COX expression was measured by flow cytometry. RESULTS AND DISCUSSION: "In situ" hybridization by flow cytometry is an useful method to detect mRNA. We observed an increased COX-2 expression in a time-dependent manner in parallel with Reactive Oxygen Species synthesis. COX-1 expression increased only at 10 days.

[Monoclonal gammopathy: a frequently overlooked diagnosis]. / Gammapatía monoclonal: un diagnóstico frecuentemente soslayado.

OBJECTIVE: To know the rate of occurrence of monoclonal bands in a clinical laboratory as an estimate of monoclonal gammopathy incidence, and to detect the proportion of these bands in which an explicit clinical diagnosis or follow-up request is not established. Other objectives are to describe its distribution and the characteristics of the patients. PATIENTS AND METHODS: 200 patients were studied in which a monoclonal band had been detected de novo. RESULTS: The incidence was 6.59 x 10(-4) year(-1). In 59.5% a diagnostic assumption was not stated. Most frequent diagnosis in the group of patients with a diagnosis was monoclonal gammopathy with uncertain meaning. Average age of patients was 74.4 years and the difference between percentages by sex was statistically significant. DISCUSSION: The data suggest a lack of clinical effort when the result is the appearance of a monoclonal band. There is no discrepancy in the distribution of the bands and in the characteristics of the patients with regard to what is described in other studies.

Gammapatía monoclonal: un diagnóstico frecuentemente soslayado / Monoclonal gammopathy: a frequently overlooked diagnosis

Objetivo. Conocer la frecuencia de aparición de bandas monoclonales en un laboratorio clínico como estimación de incidencia de gammapatía monoclonal y la proporción de estas bandas en las que no se establece un diagnóstico clínico explícito o propuesta de seguimiento. Otros objetivos son describir su distribución y las características de los pacientes. Pacientes y métodos. Se estudiaron 200 pacientes en los que se había detectado de novo una banda monoclonal. Resultados. La incidencia fue de 6,59 x 10-4 año-1. En el 59,5% no constaba una estimación diagnóstica. En el grupo de diagnosticados la más frecuente fue gammapatía monoclonal de significado incierto. La edad media de los pacientes fue de 74,4 años y la diferencia entre porcentajes por sexo fue estadísticamente significativa. Discusión. Los datos sugieren una falta de esfuerzo clínico cuando el resultado es la aparición de una banda monoclonal. No existe discrepancia en la distribución de las bandas y características de los pacientes respecto a lo descrito en otros estudios (AU)

Objective. To know the rate of occurence of monoclonal bands in a clinical laboratory as an estimate of monoclonal gammopathy incidence, and to detect the proportion of these bands in which an explicit clinical diagnosis or follow-up request is not established. Other objectives are to describe its distribution and the characteristics of the patients. Patients and methods. 200 patients were studied in which a monoclonal band had been detected de novo. Results. The incidence was 6.59 x 10-4 year-1. In 59.5% a diagnostic assumption was not stated. Most frequent diagnosis in the group of patients with a diagnosis was monoclonal gammopathy with uncertain meaning. Average age of patients was 74.4 years and the difference between percentages by sex was statistically significant. Discussion. The data suggest a lack of clinical effort when the result is the appearance of a monoclonal band. There is no discrepancy in the distribution of the bands and in the characteristics of the patients with regard to what is described in other studies (AU)

Antioxidant nutrients protect against cyclosporine A nephrotoxicity.

The immunosuppressive drug cyclosporine A (CsA) has been successfully used in several diseases with immunological basis and in transplant patients. Nephrotoxicity is the main secondary effect of CsA treatment. Although the mechanisms of nephrotoxitity are not completely defined, there is evidence that suggests the role of reactive oxygen species (ROS) in its pathogenesis. It has been demonstrated in numerous in vivo and in vitro experiments that CsA induced renal failure and increased the synthesis of ROS, thromboxane (TX) and lipid peroxidation products in the kidney. Furthermore, CsA modified the expression and activity of several renal enzymes (ciclooxygenase, superoxide-dismutase, catalase and glutathione-peroxidase). Antioxidant nutrients (e.g. Vitamins E and C) can neutralize some of the effects that CsA produced in the kidney. Thus, Vit E inhibited the synthesis of ROS and TX and the lipid peroxidation process induced by CsA in kidney structures. Antioxidants can also improve renal function and histological damage produced by CsA administration. Although there are few data in humans treated with CsA, the possibility exists that antioxidants can also neutralize CsA nephrotoxicity and LDL oxidation. Thus, antioxidant nutrients could have a therapeutic role in transplant patients treated with CsA.

[Autosomal dominant polycystic kidney disease. A comparative genetic and clinico-radiological study between patients with normal renal function and their healthy relatives]. / Enfermedad renal poliquística autosómica dominante. Estudio genético y clínico-radiológico comparativo entre los pacientes con función renal normal y sus familiares sanos.

We studied 6 families with autosomal dominant polycystic kidney disease (ADPKD), to compare patients with normal renal function and healthy family members. From 38 subjects, 20 were carried of the genetic abnormality associated to the disease (however, in 4 renal cysts were absent) and 18 were healthy relatives. We did not found any difference between the two groups in respect to clinical manifestations, physical examination or blood chemistry and renal function tests studied, except an increase of phosphaturia in ADPKD patients. However, an increase in kidney size in ADPKD was noted, more evident in hypertensive patients. The blood pressure was correlated with kidney size in patients with ADPKD, but not in healthy relatives. We conclude that in early stages of the disease, patients with ADPKD do not have clinical or analytical abnormalities although they have an increase in kidney size. Genetic studies have great value to detect patients in early stages of the disease.