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1.
Sci Rep ; 13(1): 11680, 2023 Jul 19.
Article in English | MEDLINE | ID: mdl-37468564

ABSTRACT

In recent years, significant progress has been made in laser wakefield acceleration (LWFA), both regarding the increase in electron energy, charge and stability as well as the reduction of bandwidth of electron bunches. Simultaneous optimization of these parameters is, however, still the subject of an ongoing effort in the community to reach sufficient beam quality for next generation's compact accelerators. In this report, we show the design of slit-shaped gas nozzles providing centimeter-long supersonic gas jets that can be used as targets for the acceleration of electrons to the GeV regime. In LWFA experiments at the Centre for Advanced Laser Applications, we show that electron bunches are accelerated to [Formula: see text] using these nozzles. The electron bunches were injected into the laser wakefield via a laser-machined density down-ramp using hydrodynamic optical-field-ionization and subsequent plasma expansion on a ns-timescale. This injection method provides highly controllable quasi-monoenergetic electron beams with high charge around [Formula: see text], low divergence of [Formula: see text], and a relatively small energy spread of around [Formula: see text] at [Formula: see text]. In contrast to capillaries and gas cells, the scheme allows full plasma access for injection, probing or guiding in order to further improve the energy and quality of LWFA beams.

2.
Rev Med Chil ; 147(6): 808-812, 2019 Jun.
Article in Spanish | MEDLINE | ID: mdl-31859836

ABSTRACT

Eighty percent of hepatocarcinomas are inoperable at the moment of diagnosis. Liver transplantation is the treatment of choice in these cases, but local therapies are another alternative. Among these, Image-Guided BrachyAblation is a safe choice. We report a 76-year-old male with a hepatocarcinoma, who was considered inoperable due to the high surgical risk of the patient. A local treatment with Image-Guided BrachyAblation was decided. A brachytherapy needle was placed in the tumor under computed tomography guidance and a 15 Gy single dose was delivered from an Iridium-192 source. The patient had no immediate complications and at one month of follow up he continued without incidents.


Subject(s)
Ablation Techniques/methods , Brachytherapy/methods , Carcinoma, Hepatocellular/radiotherapy , Liver Neoplasms/radiotherapy , Radiotherapy, Image-Guided/methods , Aged , Carcinoma, Hepatocellular/diagnostic imaging , Humans , Iridium Radioisotopes , Liver Neoplasms/diagnostic imaging , Male , Radiation Dosage , Tomography, X-Ray Computed , Treatment Outcome
3.
Rev. méd. Chile ; 147(6): 808-812, jun. 2019. graf
Article in Spanish | LILACS | ID: biblio-1020731

ABSTRACT

Eighty percent of hepatocarcinomas are inoperable at the moment of diagnosis. Liver transplantation is the treatment of choice in these cases, but local therapies are another alternative. Among these, Image-Guided BrachyAblation is a safe choice. We report a 76-year-old male with a hepatocarcinoma, who was considered inoperable due to the high surgical risk of the patient. A local treatment with Image-Guided BrachyAblation was decided. A brachytherapy needle was placed in the tumor under computed tomography guidance and a 15 Gy single dose was delivered from an Iridium-192 source. The patient had no immediate complications and at one month of follow up he continued without incidents.


Subject(s)
Humans , Male , Aged , Brachytherapy/methods , Carcinoma, Hepatocellular/radiotherapy , Ablation Techniques/methods , Radiotherapy, Image-Guided/methods , Liver Neoplasms/radiotherapy , Radiation Dosage , Iridium Radioisotopes , Tomography, X-Ray Computed , Treatment Outcome , Carcinoma, Hepatocellular/diagnostic imaging , Liver Neoplasms/diagnostic imaging
4.
Sci Rep ; 8(1): 4147, 2018 03 07.
Article in English | MEDLINE | ID: mdl-29515128

ABSTRACT

LPS-ligation to CD14/TLR-4 on monocytes/macrophages triggers the production of IL-12-family cytokines. IL12/18 promote TH1-differentiation, counteracting the TH2-driven asthma. Therefore, CD14 modulation could alter the TH2-differentiation and should be taken into account when studying asthma. To analyse the alteration in CD14 levels and its association with CD14 (-159 C/T) SNP (rs2569190) in Caucasian adults with stable allergic asthma, we performed a cross-sectional study (277 healthy subjects vs. 277 patients) where clinical parameters, CD14 values and the CD14 (-159 C/T) SNP were studied. Apart from typical biomarkers, we found an increment of neuron-specific enolase (NSE) in allergic asthma, probably linked to monocyte activity. Indeed, we evidenced increased monocyte numbers, but lower CD14 expression and normalised sCD14 values in patients. Moreover, we noticed an association of the T allele (P = 0.0162) and TT genotype (P = 0.0196) of the CD14 SNP with a decreased risk of allergic asthma and augmented sCD14 levels. In conclusion, monocyte CD14 expression and normalized sCD14 values were reduced in stable state asthmatics, and this could be related to the presence of an expanded CD14low monocyte subset. This study also demonstrates that the CD14 (-159 C/T) polymorphism is a risk factor for moderate-severe allergic asthma in adult Caucasians.


Subject(s)
Asthma/genetics , Lipopolysaccharide Receptors/genetics , Monocytes/metabolism , Polymorphism, Single Nucleotide , Adult , Asthma/blood , Asthma/pathology , Biomarkers/blood , Case-Control Studies , Female , Gene Expression Regulation , Humans , Leukocyte Count , Lipopolysaccharide Receptors/biosynthesis , Male , Middle Aged , Monocytes/pathology
5.
J Investig Allergol Clin Immunol ; 28(2): 113-125, 2018.
Article in English | MEDLINE | ID: mdl-29297467

ABSTRACT

BACKGROUND AND OBJETIVE: The pathogenesis of asthma is dependent on the balance between regulatory and effector T cells, which display differential expression of CD25 and CD26. Therefore, alteration of circulating levels of sCD25 and sCD26 during allergic asthma could be conditioned by changes in leukocyte phenotype. Objectives: To analyze expression of CD25 and CD26 on T lymphocytes and their soluble derivatives (sCD25, sCD26) during stable phases of moderate-severe allergic asthma. METHODS: Cross-sectional study with 2 adult cohorts of allergic asthmatics. Clinical, anthropometric, pulmonary, hematological, and biochemical parameters were measured. Phenotyping was performed with flow cytometry in both circulating and cultured leukocytes. Dipeptidyl peptidase 4 (DPP4) activity was assayed in culture supernatants. RESULTS: In vitro studies revealed upregulation of CD26 on human T lymphocytes upon activation, especially under TH17-favoring conditions, and a correlation with soluble DPP4 activity (rs=0.641; P<.001). CD26 expression on lymphocytes was higher in asthmatics, while serum sCD26 was lower in women and patients. The latter finding could be associated with an expanded CD25low/CD26low/CD127low subset of effector CD4+ T cells in allergic asthma, with no changes in Treg percentages. However, women showed an increased Teff/Treg ratio, which could explain their greater susceptibility to asthma. CONCLUSIONS: Allergic asthma causes an increment in CD25lowCD26low helper T cells detected in stable stages. These changes are mirrored in serum and should be considered in the light of the downmodulating role of CD26 in major chemokines related to the pathogenesis of asthma such as CCL11 (eotaxin), CCL5 (RANTES), and CXCL12a (SDF-1α).


Subject(s)
Asthma/immunology , CD4-Positive T-Lymphocytes/immunology , Dipeptidyl Peptidase 4/immunology , Hypersensitivity/immunology , T-Lymphocytes, Regulatory/immunology , Th17 Cells/immunology , Adult , Chemokine CCL11/immunology , Chemokine CCL5/immunology , Chemokine CXCL12/immunology , Cross-Sectional Studies , Down-Regulation/immunology , Female , Flow Cytometry/methods , Humans , Interleukin-2 Receptor alpha Subunit/immunology , Male , Middle Aged , Up-Regulation/immunology , Young Adult
7.
Rev Med Chil ; 144(6): 788-95, 2016 Jun.
Article in Spanish | MEDLINE | ID: mdl-27598500

ABSTRACT

BACKGROUND: Teaching practice is one of the most complex topics of the training process in medicine and other health care careers. The Teaching Practices Questionnaire (TPQ) evaluates teaching skills. AIM: To assess the factor structure and internal consistency of the Spanish version of the TPP among health care teachers. MATERIAL AND METHODS: The TPQ was answered by 315 university teachers from 13 of the 15 administrative Chilean regions, who were selected through a non-probabilistic volunteer sampling. The internal consistency of TPP factors was calculated and the correlation between them was analyzed. RESULTS: Six factors were identified: Student-centered teaching, Teaching planning, Assessment process, Dialogue relationship, Teacher-centered teaching and Use of technological resources. They had Cronbach alphas ranging from 0.60 to 0.85. CONCLUSIONS: The factorial structure of TPQ differentiates the most important functions of teaching. It also shows a theoretical consistency and a practical relevance to perform a diagnosis and continuous evaluation of teaching practices. Additionally, it has an adequate internal consistency. Thus, TPQ is valid and reliable to evaluate pedagogical practices in health care careers.


Subject(s)
Faculty , Schools, Health Occupations , Teaching , Adult , Aged , Chile , Factor Analysis, Statistical , Female , Humans , Male , Middle Aged , Surveys and Questionnaires , Young Adult
9.
Rev Med Chil ; 143(7): 847-55, 2015 Jul.
Article in Spanish | MEDLINE | ID: mdl-26361020

ABSTRACT

BACKGROUND: Squamous Cell Carcinoma (SCC) of the lip represents about 20% of all oral carcinomas. It is more common in men, peaking during their sixth and seventh decade, and is more prevalent in the lower lip. AIM: To determine the five years survival rate of Chilean patients with lip SCC. MATERIAL AND METHODS: The registry of the Chilean National Cancer Institute was reviewed to retrieve the clinical records of patients with lip SCC. Information about age, sex, alcohol consumption, smoking, degree of pathological differentiation, lip location, type of treatment and metastases was recorded. Survival was determined with death certificates from the National Identification Service. RESULTS: Seventy four patients were identified. Their 5-year survival was 73%. CONCLUSIONS: The survival rate of this group of patients is lower than that of patients from Unites States who have an 89.5% survival, according to the Surveillance, Epidemiology, and End Results Program of the North American National Cancer Institute.


Subject(s)
Carcinoma, Squamous Cell/mortality , Lip Neoplasms/mortality , Adult , Aged , Aged, 80 and over , Chile/epidemiology , Female , Humans , Male , Middle Aged , Prevalence , Risk Factors , Survival Analysis , Survival Rate , Time Factors
10.
Rev. méd. Chile ; 143(7): 847-855, jul. 2015. graf, tab
Article in Spanish | LILACS | ID: lil-757908

ABSTRACT

Background: Squamous Cell Carcinoma (SCC) of the lip represents about 20% of all oral carcinomas. It is more common in men, peaking during their sixth and seventh decade, and is more prevalent in the lower lip. Aim: To determine the five years survival rate of Chilean patients with lip SCC. Material and Methods: The registry of the Chilean National Cancer Institute was reviewed to retrieve the clinical records of patients with lip SCC. Information about age, sex, alcohol consumption, smoking, degree of pathological differentiation, lip location, type of treatment and metastases was recorded. Survival was determined with death certificates from the National Identification Service. Results: Seventy four patients were identified. Their 5-year survival was 73%. Conclusions: The survival rate of this group of patients is lower than that of patients from Unites States who have an 89.5% survival, according to the Surveillance, Epidemiology, and End Results Program of the North American National Cancer Institute.


Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Carcinoma, Squamous Cell/mortality , Lip Neoplasms/mortality , Chile/epidemiology , Prevalence , Risk Factors , Survival Analysis , Survival Rate , Time Factors
11.
Int. j. odontostomatol. (Print) ; 7(3): 415-419, Dec. 2013. ilus
Article in Spanish | LILACS | ID: lil-696572

ABSTRACT

La caries dental es una de las enfermedades mas prevalentes en la población mundial y más aún en los países en desarrollo, por lo que se necesitan nuevas medidas para su prevención. Estudios previos señalan que el efecto de cepas probióticas inhibe la colonización de los patógenos responsables de la caries dental como el Streptococcus mutans, previniendo la aparición de la caries dental. El objetivo fue medir el efecto de las cepas probióticas Lactobacillus casei variedad rhamnosus (LCR32) y Lactobacillus johnsonii (LA1) sobre le crecimiento in vitro de Streptococcus mutans. Se midió el efecto in vitro de las cepas de dos probióticos comercializados en Chile; Lactobacillus casei variedad rhamnosus (LCR32) contenidas en Lactil® y Lactobacillus johnsonii (LA1) contenidas en Chamyto, sobre el crecimiento in vitro de Streptococcus mutans. Se realizaron medios de cultivo selectivos para Streptococcus mutans a los cuales se les adicionaron cuatro diluciones diferentes de cada probiótico y se midió el halo de inhibición de los Streptococcus mutans con un pie de metro. Los probióticos con las cepas Lactobacillus casei variedad rhamnosus (LCR32) y Lactobacillus johnsonii (LA1) inhiben el crecimiento sobre Streptococcus mutans. Ambos probióticos en las dos concentraciones más altas no obtuvieron diferencias significativas en relación a los halos de inhibición. Sin embargo, el probiótico con la cepa Lactobacillus casei variedad rhamnosus (LCR35), mostró halos de inhibición más significativos en comparación a la cepa Lactobacillus johnsonii (LA1). Las cepas probióticas Lactobacillus casei variedad rhamnosus (LCR35) y Lactobacillus Johnosonii (LA1) disminuyen la colonización de las principales bacterias productoras de caries dental, de tal forma estos probióticos podrían ser utilizados como apoyo en la prevención y profilaxis de la enfermedad en pacientes de alto riesgo cariogénico, en forma adicional a otros medios de prevención.


Dental caries is one of the most prevalent diseases in the world and even more in the population of developing countries, so it is necessary to use new measures for prevention. Previous studies indicate that the effect of probiotic strains inhibit colonization of pathogens responsible for dental caries such as Streptococcus mutans, preventing the onset of dental caries. The aim was to measure the effect of the probiotic strains Lactobacillus casei variety rhamnosus (LCR32) and Lactobacillus johnsonii (LA1) on in vitro growth will Streptococcus mutans. We measured the effect in vitro of two probiotic strains marketed in Chile; Lactobacillus casei variety rhamnosus (LCR32) contained in Lactyl ® and Lactobacillus johnsonii (LA1) contained in Chamyto on in vitro growth of Streptococcus mutans. Culture media were made selective for Streptococcus mutans to which were added four different dilutions of each probiotic and measured the zone of inhibition of Streptococcus mutans with a foot tube. The probiotic strains Lactobacillus casei variety rhamnosus (LCR32) and Lactobacillus johnsonii (LA1) inhibit the growth of Streptococcus mutans. Both probiotics in the two higher concentrations no significant differences in relation to the zones of inhibition. However, the probiotic strain Lactobacillus casei rhamnosus variety (LCR35) showed the most significant zones of inhibition compared to the strain Lactobacillus johnsonii (LA1). The probiotic strains Lactobacillus casei rhamnosus variety (LCR35) and Lactobacillus Johnosonii (LA1) decreased the colonization of the main dental caries producing bacteria, so these probiotic could be used as support in the prevention and prophylaxis of the disease in high-risk cariogenic patients, additionally in other means of prevention.


Subject(s)
Humans , Dental Caries/microbiology , Dental Caries/prevention & control , Lactobacillus/physiology , Probiotics , Streptococcus mutans/growth & development , Lacticaseibacillus casei/physiology
12.
Int J Obes (Lond) ; 35(2): 292-9, 2011 Feb.
Article in English | MEDLINE | ID: mdl-20548300

ABSTRACT

AIM: To study the prevalence of hypertriglyceridemic waist (HTGW) in an urban adult Spanish population and its association with type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD). METHODS: We undertook a cross-sectional analysis in a random sample of 2270 individuals (18-80 years of age). All participants provided a clinical history and underwent a physical examination. Blood and urine analyses were conducted. HTGW was diagnosed using anthropometric criteria for the European population (waist circumference: for men, ≥ 94 cm; for women, ≥ 80 cm) and fasting plasma triglycerides (TGs) ≥ 1.71 mmol l(-1) (≥ 150 mg per 100 ml). RESULTS: The prevalence of HTGW was 14.5% (men: 18.2%, women: 10.8%) and was significantly greater in men <59 years (P<0.001). HTGW was associated with older individuals, a low educational level and, in men, with a sedentary lifestyle (P<0.001). Subjects with HTGW had higher levels of total cholesterol, low-density lipoprotein-cholesterol (LDL-c) and uric acid, lower levels of high-density lipoprotein-cholesterol, a higher blood pressure, a greater degree of obesity and a higher prevalence of T2DM (20.00 vs 6.4%, P<0.001) (odds ratio (OR) 3.61; 95% confidence interval (95% CI), 2.60-5.01) and CVD (8.5 vs 3.4%, P<0.001) (OR 2.63; 95% CI, 1.66-4.16). The association of HTGW with T2DM and CVD disappeared after adjusting for age. The degree of concordance between HTGW and the metabolic syndrome (MS) was moderate, with both the Adult Treatment Panel III Report (ATP-III) and the International Diabetes Federation criteria (κ=0.51 and κ=0.58, respectively). Subjects with isolated HTGW as compared with those with isolated MS (ATP-III) were younger, had greater levels of total cholesterol, LDL-c and TGs and a lower prevalence of obesity, high blood pressure and dysglycemia. CONCLUSION: HTGW is a phenotype of cardiometabolic risk prevalent in the adult population in our environment. HTGW may be an alternative to MS to detect the population at risk for T2DM and CVD, especially in young individuals who do not fulfill the criteria for MS.


Subject(s)
Cardiovascular Diseases/epidemiology , Diabetes Mellitus, Type 2/epidemiology , Diabetic Angiopathies/epidemiology , Hypertriglyceridemia/epidemiology , Obesity, Abdominal/epidemiology , Adolescent , Adult , Aged , Aged, 80 and over , Cardiovascular Diseases/blood , Cholesterol/blood , Cholesterol, HDL/blood , Cross-Sectional Studies , Diabetes Mellitus, Type 2/blood , Diabetic Angiopathies/blood , Diabetic Angiopathies/physiopathology , Female , Humans , Hypertriglyceridemia/blood , Male , Middle Aged , Obesity, Abdominal/blood , Risk Factors , Spain/epidemiology , Triglycerides/blood , Urban Health , Waist Circumference , Young Adult
13.
Rev. chil. obstet. ginecol ; 72(1): 5-10, 2007. ilus, tab
Article in Spanish | LILACS | ID: lil-627345

ABSTRACT

OBJETIVO: Analizar la dosimetría en braquiterapia ginecólogica para el dispositivo Fletcher-Suit-Delclos con alta tasa de dosis, mediante placas radiográficas ortogonales (anteroposterior y lateral) versus tomografía axial computada (TAC). MATERIAL Y MÉTODOS: Se compararon dosimetrías de 4 implantes, realizadas con placas ortogonales y TAC pélvico en la Unidad de Braquiterapia del Instituto Nacional del Cáncer durante el mes de febrero del año 2006. Se prescribieron dosis de 8 Gy/fracción a punto H y se evaluó dosis a vejiga, recto y vagina según norma internacional. RESULTADOS: Las dosimetrías por TAC mostraron puntos calientes superiores a las placas ortogonales, para recto un 133% y para vejiga un 260% más aproximadamente. El porcentaje de volumen blanco incluido es subestimado con la dosimetría efectuada por placas ortogonales. CONCLUSIONES: La dosimetría por placas ortogonales muestra menor exactitud que el TAC. Los volúmenes blanco no son satisfactoriamente cubiertos por la curva de isodosis prescrita. La dosis acumulada, probablemente, sea más relevante que la dosis fracción.


OBJECTIVE: We analyze the gynecologycal high dose rate brachytherapy dosimetry using the Fletcher-Suit-Delclos device, comparing orthogonal films (anteroposterior and lateral) versus axial computarized tomography. METHODS: 4 implants were analized with orthogonal films and axial computarized tomography in the Brachyhterapy Unit of the National Cancer Institute on February 2006. The dose/fraction was 8 Gy to the H point. The bladder, rectal and vaginal dose point were evaluated according to international specifications. RESULTS: Axial computarized tomography reveals hot points higher than orthogonal films dosimetries (133% and 260% for bladder and rectum respectively). The target volumen included was underestimated with the classical orthogonal film dosimetry. CONCLUSIONS: The orthogonal film dosimetry shows smaller accuracy than axial computarized tomography. The target volumens were not satisfactorily covered by the prescribed isodosis curve. The dose accumulated could, probably, be more prominent than the dose/fraction.


Subject(s)
Humans , Female , Radiotherapy Dosage , Brachytherapy/methods , Uterine Cervical Neoplasms/radiotherapy , Radiometry/standards , Rectum/radiation effects , Urinary Bladder/radiation effects , Radiotherapy, Computer-Assisted
14.
Colorectal Dis ; 8(4): 353-9, 2006 May.
Article in English | MEDLINE | ID: mdl-16630243

ABSTRACT

OBJECTIVE: Double-barrelled wet colostomy is a urinary diversion technique indicated when a concurrent faecal diversion is needed. It is a simple procedure, technically easy to accomplish and well received by patients. The purpose of this study is to report the results of double-barrelled wet colostomy, with emphasis on operating technique, morbidity, functional results and a review of the literature on the subject. METHODS: The medical records of 9 consecutive patients, between January 2001 and May 2005, who underwent surgical extended resections with double-barrelled wet colostomy for a malignant central pelvic mass, were reviewed retrospectively. The patients were asked to respond to a questionnaire assessing quality of life. The questionnaire used was the QLQ-C30 version 3, proposed by the European Organization for Research and Treatment of Cancer (EORTC). RESULTS: This study presents results obtained from 9 patients, emphasizing morbidity and quality of life. One patient presented with pyelonephritis. We did not identify complications such as hydroelectrolytic disturbances, peristomal dermatitis or hydronephrosis. The patients who submitted to the procedure exhibited high levels of quality of life and found caring for the stomas straight forward. CONCLUSIONS: We conclude that double-barrelled wet colostomy is an excellent choice for patients who require concurrent urinary and faecal diversion, one that does not present technical difficulties and does not require a prolonged operating time. It avoids the complications frequently present in standard wet colostomy and does not rule out making a continent urinary reservoir later, in patients that meet healing criteria.


Subject(s)
Anastomosis, Roux-en-Y/methods , Cecal Neoplasms/surgery , Colorectal Neoplasms/surgery , Colostomy/methods , Urinary Diversion/methods , Uterine Neoplasms/surgery , Adult , Anastomosis, Roux-en-Y/adverse effects , Cecal Neoplasms/pathology , Colorectal Neoplasms/pathology , Colostomy/adverse effects , Female , Humans , Male , Middle Aged , Neoplasm Invasiveness , Quality of Life , Retrospective Studies , Treatment Outcome , Urinary Diversion/adverse effects , Uterine Neoplasms/pathology
17.
Rheumatol Int ; 21(2): 69-74, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11732862

ABSTRACT

CD26, a transmembrane ectoenzyme, is overexpressed on rheumatoid arthritis (RA) peripheral blood T cells. As it has been recently described that IL-12 and IL-15 upregulate CD26 in vitro, we hypothesized that this CD26 overexpression might be interleukin dependent. The concentrations of IL-12 and IL-15, and soluble CD26 and adenosine deaminase (enzymes related to CD26) were analyzed in the serum of 35 patients with active and inactive RA and of healthy control subjects. IL-12 and IL-15 levels were significantly higher in patients' serum, independently of disease activity, even in patients on steroid therapy, i.e., the present therapies cannot eradicate their origin. Soluble CD26 was significantly reduced and related to the disease activity. In particular, it correlated inversely with the number of swollen joints. Although these data did not support our hypothesis, they support that interleukins not only initiate RA pathology but they can also participate in the maintenance of this immune response.


Subject(s)
Adenosine Deaminase/metabolism , Arthritis, Rheumatoid/enzymology , Arthritis, Rheumatoid/immunology , Dipeptidyl Peptidase 4/analysis , Interleukin-12/blood , Interleukin-15/blood , Adult , Aged , Aged, 80 and over , Biomarkers/blood , Enzyme-Linked Immunosorbent Assay , Female , Humans , Male , Middle Aged , Probability , Reference Values , Sensitivity and Specificity , Severity of Illness Index
18.
J Leukoc Biol ; 70(6): 920-30, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11739555

ABSTRACT

CD26 is a lymphocyte marker that can anchor adenosine deaminase (ADA) on the T cell surface. We found that ADA is regulated by cytokines on the cell surface during T cell activation. By means of flow cytometry, immunofluorescence, and immunoblotting techniques, we found that interleukin (IL)-2 and IL-12 up-regulate ecto-ADA and CD26 expression. In clear contrast, IL-4 led to down-regulation of lymphocyte surface ADA without modifying the level of CD26. Moreover, neither circulating ADA transcription nor mRNA translation was regulated by cytokines. These results, along with absence of total-ADA modulation, the variable amount of ADA found in purified plasma membranes, and the different effect of Brefeldin A on the surface presence of ADA and CD26 indicated that cytokines regulate the translocation of ADA towards the cell surface through a mechanism not involving CD26. Ecto-ADA protected activated lymphocytes from the toxic effects of extracellular adenosine. Therefore, this cell surface ADA control might constitute part of the fine immunoregulatory mechanism of adenosine-mediated signaling through purinergic receptors in leukocytes.


Subject(s)
Adenosine Deaminase/immunology , Cytokines/pharmacology , Dipeptidyl Peptidase 4/immunology , Lymphocyte Activation , T-Lymphocytes/immunology , Adenosine Deaminase/biosynthesis , Cell Membrane/enzymology , Cell Membrane/immunology , Cells, Cultured , Cytokines/immunology , Dipeptidyl Peptidase 4/biosynthesis , Humans , T-Lymphocytes/enzymology , Up-Regulation/drug effects , Up-Regulation/immunology
20.
Microbios ; 104(408): 79-85, 2001.
Article in English | MEDLINE | ID: mdl-11297014

ABSTRACT

The antibacterial activity of sixteen Chilean red wines (Cabernet Sauvignon, Cabernet Merlot, Cabernet Organic and Pinot Noir), and the active extracts of two randomly selected wines were assayed for their antibacterial activity on six strains of Helicobacter pylori isolated from gastric biopsies. The active fraction of the wines was obtained by dichloromethane extraction, and the antibacterial activity of the wines and extracts was evaluated by an agar diffusion method. All the red wines studied showed some antibacterial activity on the six strains of H. pylori, although the strains were heterogeneous in their susceptibility to each particular wine. The active fraction of the two wines selected also showed good activity against the strains tested. The main active compound was identified as resveratrol. The results presented indicate that Chilean red wines have antibacterial activity against H. pylori, which depends mainly on the presence of resveratrol.


Subject(s)
Anti-Bacterial Agents/pharmacology , Helicobacter pylori/drug effects , Wine , Chile , Helicobacter Infections/microbiology , Helicobacter pylori/growth & development , Humans
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