Acellular fraction from malignant effusions has cytotoxicity in breast cancer cells.

Malignant ascites (MA) and malignant pleural effusion (MPE) are frequently developed in patients with metastatic cancer; however, the biological properties of these fluids have not been clarified. The present study explored the biological role of a low molecular fraction derived from malignant effusions on the activation of peripheral blood mononuclear cells and on the proliferation of breast cancer cells and fibroblast 55x cells. A <10-kDa fraction from effusions of 41 oncological patients and 34 individuals without cancer was purified, and its potential role in inhibiting nitric oxide (NO) production on lipopolysaccharide (LPS)-stimulated peripheral blood mononuclear cells was explored, as well as its cytotoxicity on MCF-7 breast cancer cells and fibroblast 55x cells. A significant decrease in NO production was observed in the <10-kDa fraction from malignant effusions. In addition, the acellular fraction from MA decreased the viability of breast cancer cells without affecting human fibroblasts. These data support the presence of low molecular weight molecules in malignant samples with a specific role in inhibiting the defense mechanisms of peripheral blood mononuclear cells and decreasing the viability of breast cancer cells in vitro.

Radiogenomics analysis identifies correlations of digital mammography with clinical molecular signatures in breast cancer.

In breast cancer, well-known gene expression subtypes have been related to a specific clinical outcome. However, their impact on the breast tissue phenotype has been poorly studied. Here, we investigate the association of imaging data of tumors to gene expression signatures from 71 patients with breast cancer that underwent pre-treatment digital mammograms and tumor biopsies. From digital mammograms, a semi-automated radiogenomics analysis generated 1,078 features describing the shape, signal distribution, and texture of tumors along their contralateral image used as control. From tumor biopsy, we estimated the OncotypeDX and PAM50 recurrence scores using gene expression microarrays. Then, we used multivariate analysis under stringent cross-validation to train models predicting recurrence scores. Few univariate features reached Spearman correlation coefficients above 0.4. Nevertheless, multivariate analysis yielded significantly correlated models for both signatures (correlation of OncotypeDX = 0.49 ± 0.07 and PAM50 = 0.32 ± 0.10 in stringent cross-validation and OncotypeDX = 0.83 and PAM50 = 0.78 for a unique model). Equivalent models trained from the unaffected contralateral breast were not correlated suggesting that the image signatures were tumor-specific and that overfitting was not a considerable issue. We also noted that models were improved by combining clinical information (triple negative status and progesterone receptor). The models used mostly wavelets and fractal features suggesting their importance to capture tumor information. Our results suggest that molecular-based recurrence risk and breast cancer subtypes have observable radiographic phenotypes. To our knowledge, this is the first study associating mammographic information to gene expression recurrence signatures.

A robust biomarker of differential correlations improves the diagnosis of cytologically indeterminate thyroid cancers.

The fine-needle aspiration of thyroid nodules and subsequent cytological analysis is unable to determine the diagnosis in 15 to 30% of thyroid cancer cases; patients with indeterminate cytological results undergo diagnostic surgery which is potentially unnecessary. Current gene expression biomarkers based on well-determined cytology are complex and their accuracy is inconsistent across public datasets. In the present study, we identified a robust biomarker using the differences in gene expression values specifically from cytologically indeterminate thyroid tumors and a powerful multivariate search tool coupled with a nearest centroid classifier. The biomarker is based on differences in the expression of the following genes: CCND1, CLDN16, CPE, LRP1B, MAGI3, MAPK6, MATN2, MPPED2, PFKFB2, PTPRE, PYGL, SEMA3D, SERGEF, SLC4A4 and TIMP1. This 15-gene biomarker exhibited superior accuracy independently of the cytology in six datasets, including The Cancer Genome Atlas (TCGA) thyroid dataset. In addition, this biomarker exhibited differences in the correlation coefficients between benign and malignant samples that indicate its discriminatory power, and these 15 genes have been previously related to cancer in the literature. Thus, this 15-gene biomarker provides advantages in clinical practice for the effective diagnosis of thyroid cancer.

Validation of the FRAIL scale in Mexican elderly: results from the Mexican Health and Aging Study.

BACKGROUND: The aging population in Latin America is characterized by not optimal conditions for good health, experiencing high burden of comorbidity, which contribute to increase the frequency of frailty; thus, identification should be a priority, to classify patients at high risk to develop its negative consequences. AIM: The objective of this analysis was to validate the FRAIL instrument to measure frailty in Mexican elderly population, from the database of the Mexican Health and Aging Study (MHAS). MATERIALS AND METHODS: Prospective, population study in Mexico, that included subjects of 60 years and older who were evaluated for the variables of frailty during the year 2001 (first wave of the study). Frailty was measured with the five-item FRAIL scale (fatigue, resistance, ambulation, illnesses, and weight loss). The robust, pre-frail or intermediate, and the frail group were considered when they had zero, one, and at least two components, respectively. Mortality, hospitalizations, falls, and functional dependency were evaluated during 2003 (second wave of the study). Relative risk was calculated for each complications, as well as hazard ratio (for mortality) through Cox regression model and odds ratio with logistic regression (for the rest of the outcomes), adjusted for covariates. RESULTS: The state of frailty was independently associated with mortality, hospitalizations, functional dependency, and falls. The pre-frailty state was only independently associated with hospitalizations, functional dependency, and falls. CONCLUSIONS: Frailty measured through the FRAIL scale, is associated with an increase in the rate of mortality, hospitalizations, dependency in activities of daily life, and falls.

Integration and comparison of different genomic data for outcome prediction in cancer.

BACKGROUND: In cancer, large-scale technologies such as next-generation sequencing and microarrays have produced a wide number of genomic features such as DNA copy number alterations (CNA), mRNA expression (EXPR), microRNA expression (MIRNA), and DNA somatic mutations (MUT), among others. Several analyses of a specific type of these genomic data have generated many prognostic biomarkers in cancer. However, it is uncertain which of these data is more powerful and whether the best data-type is cancer-type dependent. Therefore, our purpose is to characterize the prognostic power of models obtained from different genomic data types, cancer types, and algorithms. For this, we compared the prognostic power using the concordance and prognostic index of models obtained from EXPR, MIRNA, CNA, MUT data and their integration for ovarian serous cystadenocarcinoma (OV), multiform glioblastoma (GBM), lung adenocarcinoma (LUAD), and breast cancer (BRCA) datasets from The Cancer Genome Atlas repository. We used three different algorithms for prognostic model selection based on constrained particle swarm optimization (CPSO), network feature selection (NFS), and least absolute shrinkage and selection operator (LASSO). RESULTS: The integration of the four genomic data produced models having slightly higher performance than any single genomic data. From the genomic data types, we observed better prediction using EXPR closely followed by MIRNA and CNA depending on the cancer type and method. We observed higher concordance index in BRCA, followed by LUAD, OV, and GBM. We observed very similar results between LASSO and CPSO but smaller values in NFS. Importantly, we observed that model predictions highly concur between algorithms but are highly discordant between data types, which seems to be dependent on the censoring rate of the dataset. CONCLUSIONS: Gene expression (mRNA) generated higher performances, which is marginally improved when other type of genomic data is considered. The level of concordance in prognosis generated from different genomic data types seems to be dependent on censoring rate.

Alelo C del polimorfismo rs2209972 del gen de la enzima degradadora de insulina y enfermedad de Alzheimer en diabéticos tipo 2. Estudio de casos y controles / C allele of the rs2209972 single nucleotide polymorphism of the insulin degrading enzyme gene and Alzheimer's disease in type 2 diabetes, a case control study

Background and objective: In the last few decades we have witnessed an interesting transformation of the population pyramids throughout the world. As the population's life expectancy increases, there are more chronic diseases such as diabetes mellitus and dementias, and both of them have shown an association. General objetive: To determine the association between Alzheimer's disease in diabetic patients and the insulin degrading enzyme in outpatients of a second level Hospital in Monterrey, Mexico. Materials and methods: This was a case control study in which we included outpatients from the Geriatrics Clinic of a Hospital in Northeastern Mexico. Cases were patients with a Mini Mental Score Exam (MMSE) below 24 and DSM-IV criteria for Dementia. Controls were patients who had MMSE scores greater than 24. Results: Data from 97 patients were analyzed. Regarding physical examination and the results of laboratory tests, there were no differences between the two groups (p > 0.05). A 98% prevalence of the insulin degrading enzyme was documented in the sample studied. We found an association between a homozygous status for the CC genotype and Dementia with an estimated Odds Ratio (OR) of 2.5 (CI 95% 1.6–3.3) on the bivariate test, while, on the multivariate analysis, the OR was estimated 3.3 (CI 95% 1.3–8.2). Conclusions: Evidence shows that cognitive impairment is more frequent among those exposed to the C allele of the rs2209972 SNP of the insulin degrading enzyme gene (AU)

Fundamento y objetivo: En las últimas décadas se ha producido una transformación en las pirámides poblacionales, con un aumento en la expectativa de vida, lo que conlleva un mayor número de enfermedades crónico-degenerativas, como son la diabetes mellitus y la demencia, que han mostrado tener una asociación estrecha, pero cuya etiología aún está por discernir. El objetivo de este estudio fue determinar la asociación entre el alelo C de la enzima degradadora de insulina y la enfermedad de Alzheimer en pacientes con diabetes tipo 2. Material y métodos: Estudio de casos y controles, en el cual se incluyeron pacientes de la clínica de Geriatría del Hospital General del Noreste de México. Los casos fueron aquellos con una puntuación en el Mini-Mental State Examination (MMSE) menor de 24 y criterios para demencia de acuerdo con el DSM-IV. Los controles fueron pacientes con MMSE superior a 24. Resultados: Se analizaron datos de 97 pacientes. No hubo diferencias respecto a las características basales clínicas y de laboratorio entre los casos y los controles (p > 0,05). Se documentó una prevalencia de 98% del alelo C de la enzima degradadora de insulina. Encontramos una asociación entre homocigosidad para el genotipo CC de la enzima degradadora de insulina y enfermedad de Alzheimer, con una OR de 2,5 (IC 95% 1,6–3,3) en el examen bivariado, y en el examen multivariado se encontró asociación con una OR de 3,3 (IC 95% 1,3–8,2). Conclusiones: La evidencia muestra una asociación entre deterioro cognitivo y presencia del alelo C del polimorfismo rs2209972 del gen de la enzima degradadora de insulina (AU)

C allele of the rs2209972 single nucleotide polymorphism of the insulin degrading enzyme gene and Alzheimer's disease in type 2 diabetes, a case control study.

BACKGROUND AND OBJECTIVE: In the last few decades we have witnessed an interesting transformation of the population pyramids throughout the world. As the population's life expectancy increases, there are more chronic diseases such as diabetes mellitus and dementias, and both of them have shown an association. GENERAL OBJETIVE: To determine the association between Alzheimer's disease in diabetic patients and the insulin degrading enzyme in outpatients of a second level Hospital in Monterrey, Mexico. MATERIALS AND METHODS: This was a case control study in which we included outpatients from the Geriatrics Clinic of a Hospital in Northeastern Mexico. Cases were patients with a Mini Mental Score Exam (MMSE) below 24 and DSM-IV criteria for Dementia. Controls were patients who had MMSE scores greater than 24. RESULTS: Data from 97 patients were analyzed. Regarding physical examination and the results of laboratory tests, there were no differences between the two groups (p>0.05). A 98% prevalence of the insulin degrading enzyme was documented in the sample studied. We found an association between a homozygous status for the CC genotype and Dementia with an estimated Odds Ratio (OR) of 2.5 (CI 95% 1.6-3.3) on the bivariate test, while, on the multivariate analysis, the OR was estimated 3.3 (CI 95% 1.3-8.2). CONCLUSIONS: Evidence shows that cognitive impairment is more frequent among those exposed to the C allele of the rs2209972 SNP of the insulin degrading enzyme gene.

Asociación entre el polimorfismo c.1-765G>C del gen de la COX-2 y el deterioro cognitivo en individuos diabéticos de 65 o mas años de un Servicio de Geriatría en Monterrey, México / Association between polymorphism c.1-765G>C of the COX2 gene and cognitive impairment in individuals 65 years or more with diabetes from a Geriatric Service in Monterrey, Mexico

Background and objective: Cognitive impairment and dementia are common geriatric syndromes in diabetic patients. Inflammation plays a crucial role in the pathophysiology of Alzheimer's disease and cognitive impairment. Cyclooxygenases (COX) 1 and 2 participate in inflammation. The polymorphism c.1-765G>C of the COX2 gene might be protective against cognitive decline in Mexicans with diabetes mellitus through its reduced promotor activity. To determine the association between polymorphism c.1-765G>C of the COX2 gene and cognitive impairment in elderly adults with diabetes. Patients and methods: Case-control study. We included diabetic patients from the Geriatric Clinic of General Hospital No. 17 who were over 65 years and accepted to participate. Cases were patients with a score of 24 or less on the Mini Mental Status Examination (MMSE) and with DSM IV criteria for dementia. Controls were those with MMSE scores of 25 or greater. Results: We included 97 patients (50 cases and 47 controls). There were no differences regarding clinical and laboratory characteristics between cases and controls. The frequency of the C allele and the CG genotype was higher in controls than in cases and this difference remained significant in a multivariate analysis with an odds ratio of 0.012 (95% CI 0.001-0.091) and 0.009 (95% CI 0.001-0.076) in the bivariate and multivariate analysis, respectively, using the GG genotype frequency as a reference. Conclusion: Cognitive impairment in Mexican patients with diabetes is associated with less exposure to the CG genotype of the c.1-765G>C polymorphism of COX2 (AU)

Fundamento y objetivo: El deterioro cognitivo y la demencia son síndromes geriátricos frecuentes en los pacientes con diabetes. La inflamación es crucial en la fisiopatología de la enfermedad de Alzheimer y del deterioro cognitivo. Las ciclooxigenasas (COX) 1 y 2 participan en la inflamación. El polimorfismo c.1- 765G>C de la COX-2 protegería contra el deterioro cognitivo en adultos mayores diabéticos mexicanos por su menor actividad promotora. El objetivo de este estudio fue determinar la asociación entre el polimorfismo c.1-765G>C del gen de la COX-2 y el deterioro cognitivo en adultos mayores diabéticos. Pacientes y métodos: Estudio de tipo casos y controles. Se incluyeron pacientes diabéticos de la clínica de Geriatría del Hospital General de Zona No. 17, mayores de 65 años que aceptaron participar. Los casos fueron los pacientes con puntuación de 24 o menor en el Mini-Mental State Examination (MMSE) y criterios DSM-IV para demencia. Los controles tenían una puntuación de 25 o mayor en el MMSE. Resultados: Se incluyeron 97 pacientes (50 casos y 47 controles). No hubo diferencias respecto a las características clínicas y de laboratorio entre los casos y los controles. La frecuencia del alelo C y del genotipo CG fue mayor en los controles que en los casos, y dicha diferencia permaneció significativa en el análisis multivariado, con una razón de momios de 0,012 (IC 95% 0,001 a 0,091) y de 0,009 (IC 95% 0,001 a 0,076), en el análisis bivariado y multivariado, respectivamente, tomando como referencia la frecuencia genotípica GG. Conclusión: El deterioro cognitivo en pacientes mexicanos con diabetes se asocia con una menor exposición al polimorfismo c.1-765G>C del gen de la COX-2 (AU)

Association between polymorphism c.1-765G>C of the COX2 gene and cognitive impairment in individuals 65 years or more with diabetes from a Geriatric Service in Monterrey, Mexico.

BACKGROUND AND OBJECTIVE: Cognitive impairment and dementia are common geriatric syndromes in diabetic patients. Inflammation plays a crucial role in the pathophysiology of Alzheimer's disease and cognitive impairment. Cyclooxygenases (COX) 1 and 2 participate in inflammation. The polymorphism c.1-765G>C of the COX2 gene might be protective against cognitive decline in Mexicans with diabetes mellitus through its reduced promotor activity. To determine the association between polymorphism c.1-765G>C of the COX2 gene and cognitive impairment in elderly adults with diabetes. PATIENTS AND METHODS: Case-control study. We included diabetic patients from the Geriatric Clinic of General Hospital No. 17 who were over 65 years and accepted to participate. Cases were patients with a score of 24 or less on the Mini Mental Status Examination (MMSE) and with DSM IV criteria for dementia. Controls were those with MMSE scores of 25 or greater. Results We included 97 patients (50 cases and 47 controls). There were no differences regarding clinical and laboratory characteristics between cases and controls. The frequency of the C allele and the CG genotype was higher in controls than in cases and this difference remained significant in a multivariate analysis with an odds ratio of 0.012 (95% CI 0.001-0.091) and 0.009 (95% CI 0.001-0.076) in the bivariate and multivariate analysis, respectively, using the GG genotype frequency as a reference. CONCLUSION: Cognitive impairment in Mexican patients with diabetes is associated with less exposure to the CG genotype of the c.1-765G>C polymorphism of COX2.

Trichomonas vaginalis acidic phospholipase A2: isolation and partial amino acid sequence.

Sexually transmitted diseases are a major cause of acute disease worldwide, and trichomoniasis is the most common and curable disease, generating more than 170 million cases annually worldwide. Trichomonas vaginalis is the causal agent of trichomoniasis and has the ability to destroy in vitro cell monolayers of the vaginal mucosa, where the phospholipases A2 (PLA2) have been reported as potential virulence factors. These enzymes have been partially characterized from the subcellular fraction S30 of pathogenic T. vaginalis strains. The main objective of this study was to purify a phospholipase A2 from T. vaginalis, make a partial characterization, obtain a partial amino acid sequence, and determine its enzymatic participation as hemolytic factor causing lysis of erythrocytes. Trichomonas S30, RF30 and UFF30 sub-fractions from GT-15 strain have the capacity to hydrolyze [2-(14)C-PA]-PC at pH 6.0. Proteins from the UFF30 sub-fraction were separated by affinity chromatography into two eluted fractions with detectable PLA A2 activity. The EDTA-eluted fraction was analyzed by HPLC using on-line HPLC-tandem mass spectrometry and two protein peaks were observed at 8.2 and 13 kDa. Peptide sequences were identified from the proteins present in the eluted EDTA UFF30 fraction; bioinformatic analysis using Protein Link Global Server charged with T. vaginalis protein database suggests that eluted peptides correspond a putative ubiquitin protein in the 8.2 kDa fraction and a phospholipase preserved in the 13 kDa fraction. The EDTA-eluted fraction hydrolyzed [2-(14)C-PA]-PC lyses erythrocytes from Sprague-Dawley in a time and dose-dependent manner. The acidic hemolytic activity decreased by 84% with the addition of 100 µM of Rosenthal's inhibitor.

Axenic cultivation and comparative phospholipase A2 activity of Giardia duodenalis in a serum-free medium.

Mammalian serum is essential for the growth of Giardia duodenalis cultivated under axenic conditions. Unfortunately, some factors present in bovine serum used as supplement in the culture medium may inhibit protozoal growth and activity. TYI-33-PACSR is a TYI medium supplemented with a serum replacement (PACSR) made up of Earle's amino acid solution, Diamond's vitamin-tween 80 mixtures and LCR (a lipid-cholesterol - rich mixture). PACSR was previously used in the culture media for axenic cultivation of Entamoeba histolytica and Trichomonas vaginalis. The main objective of this work was to demonstrate that TYI-33-PACSR is useful for axenic cultivation of G. duodenalis. Additionally, the activity of phospholipase A(2) (PLA A(2)) in the sub-cellular vesicular fraction (P30) of G. duodenalis grown in TYI-S-33 and TYI-33-PACSR was compared. All strains of Giardia grown in TYI-33-PACSR reached relative cellular densities of 91 to 95% compared to controls growing in serum-supplemented TYI-S-33 medium. Additionally, PLA A(2) activity was similar in the P30 sub-cellular fraction obtained from trophozoites growing in TYI-S-33 and TYI-33-PACSR. Thus, TYI-33-PACSR could be useful in analyzing the biological properties of G. duodenalis in the absence of serum.

Galectin labeling of cells from paraffinized tissues may serve as a diagnostic tool in the detection and classification of thyroid carcinomas.

This study seeks to determine whether the relative levels of attachment to galectins 1 and 3 of cells from thyroid tissues embedded in paraffin blocks can differentiate thyroid tumors from normal tissues. A total of 48 thyroid paraffin sample blocks from 4 groups of patients were analyzed: 12 samples served as controls, 12 samples were from patients with thyroid adenoma, 12 samples were from patients with thyroid follicular carcinoma, and 12 samples were from patients with thyroid papillary carcinoma. The relative attachment of cells to galectins 1 and 3 antigens was determined using the InnoCyte™ ECM Cell Adhesion kit at different cell sample concentrations. All of the samples from thyroid tissue preparations showed attachment to galectins 1 and 3. The samples from tissues with a diagnosis of adenoma, follicular and papillary carcinoma showed an increased adherence to galectins 1 and 3 relative to the controls. Significant differences were found between the means of the adherent cells from the adenomas compared with the follicular and papillary carcinoma samples. When the outcomes from the galectins 1 and 3 cell surface binding were compared, no statistical differences were found. The cells from adenoma and carcinoma samples show more adhesion to galectins 1 and 3 than cells from the control samples. The samples prepared from follicular and papillary carcinomas show more cells adherent to galectins 1 and 3 than those from the adenomas.

Entamoeba histolytica: soluble and membrane-associated neutral sphingomyelinase-C and other unidentified esterase activity.

Sphingomyelinase (SMase) activity was measured in Entamoeba histolytica particulate and soluble subcellular fractions. The effects on SMase of incubation time, total protein concentration, pH, and several divalent cations were determined. SMase-C and other unidentified esterase activity were detected in soluble and particulate fractions. SMase-C was 94.5-96.0% higher than the unidentified esterase activity. Soluble and insoluble SMase-C specific activities increased with protein dose and incubation time. Soluble and insoluble SMase-C activities were maximum at pH 7.5 and were dependent on Mg(2+), Mn(2+), or Co(2+), and inhibited by Zn(2+), Hg(2+), Ca(2+), and EDTA. SMase-C was active in the pH range of 3-10 and its maximum activity was at pH 7.5. The soluble and insoluble SMases have remarkably similar physicochemical properties, strongly suggesting that E. histolytica has just one isoform of neutral SMase-C that had not been described before and might be essential for E. histolytica metabolism or virulence.

Activity of intracellular phospholipase A1 and A2 in Giardia lamblia.

Neither phospholipase A1 (PLA A1) nor phospholipase A2 (PLA A2), nor their respective genes, have been identified in Giardia lamblia, even though they are essential for lipid metabolism in this parasite. A method to identify, isolate, and characterize these enzymes is needed. The activities of PLA A1 and PLA A2 were analyzed in a total extract (TE) and in vesicular (P30) and soluble (S30) subcellular fractions of G. lamblia trophozoites; the effects of several chemical and physicochemical factors on their activities were investigated. The assays were performed using substrate labeled with 14C, and the mass of the 14C-product was quantified. PLA A1 and PLA A2 activity was present in the TE and the P30 and S30 fractions, and it was dependent on pH and the concentrations of protein and Ca2+. In all trophozoite preparations, PLA A1 and PLA A2 activities were inhibited by ethylenediaminetetraacetic acid and Rosenthal's inhibitor. These results suggest that G. lamblia possesses several PLA A1 and PLA A2 isoforms that may be soluble or associated with membranes. In addition to participating in G. lamblia phospholipid metabolism, PLA A1 and PLA A2 could play important roles in the cytopathogenicity of this parasite.

Macrophage-activation inhibitor factor from L5178Y murine lymphoma and formation of hepatic abscesses in BALB/c mice.

BACKGROUND: Normal mice are naturally resistant to hepatic abscesses produced by Listeria monocytogenes. A macrophage-activation inhibitor factor (MAIF) isolated from the cell-free ascitic fluid of L5178Y lymphoma-bearing mice inhibited the lipopolysaccharide-induced production of nitric oxide (NO) by the macrophages. Because macrophages are also involved in the immune response towards L. monocytogenes, the present study had the objective of investigating whether MAIF was also capable of allowing L. monocytogenes to form hepatic abscesses. METHODS: BALC/c mice were inoculated intrahepatically with 5 x 10(5) bacteria. Experimental groups were treated daily with subcutaneous or intraperitoneal doses of 0, 1, 5 or 10 microg of MAIF/g of body weight. One dose was applied before inoculating bacteria and the remaining three doses 24, 48, and 72 h after inoculating bacteria. The development of hepatic abscess was analyzed 24 h after the last administration of MAIF. RESULTS: All treated mice (but not controls) developed hepatic abscess showing no differences regarding MAIF administration route. CONCLUSIONS: These results suggest a possible MAIF in vivo inhibition of NO macrophage production that allows L. monocytogenes hepatic abscess development in mice.

Trichomonas vaginalis: identification of soluble and membrane-associated phospholipase A1 and A2 activities with direct and indirect hemolytic effects.

A direct hemolytic activity, dependent on phospholipase A (PLA) activity, was located in the particulate subcellular fraction (P30) of Trichomonas vaginalis. We identified soluble direct and indirect hemolytic activities in the spent medium and soluble fraction (S30) of T. vaginalis strain GT-13. Spent medium showed the highest specific indirect hemolytic activity (SIHA) at pH 6.0 (91 indirect hemolytic units [HU]/mg/hr). Spent medium and P30, but not S30, showed direct hemolytic activity. PLA activity was protein dose dependent and time dependent. The highest PLA activity was observed at pH 6.0. All trichomonad preparations showed phospholipase A1 (PLA A1) and phospholipase A2 (PLA A2) activities. Indirect and direct hemolytic activity and PLA A1 and PLA A2 diminished at pH 6.0 and 8.0 with increasing concentrations of Rosenthal's inhibitor. The greatest effect was observed with 80 microM at pH 6.0 on the SIHA of S30 (83% reduction) and the lowest at pH 8.0, also on the SIHA of S30 (26% reduction). In conclusion, T. vaginalis contains particulate and soluble acidic, and alkaline direct and indirect hemolytic activities, which are partially dependent on alkaline or acidic PLA A1 and PLA A2 enzymes. These could be responsible for the contact-dependent and -independent hemolytic and cytolytic activities of T. vaginalis.

Detection of a factor released by L5178Y lymphoblasts that inhibits mouse Macrophage-Activation induced by lipopolysaccharides

Background. Several factors inhibit cellular immune response by deactivating macrophages, but very few, such as those described here, prevent macrophage activation. Methods. Ascites liquid from 12-day-old BALB/c mice bearing 5178Y lymphoma tumors was collected, and cell-free ascites liquid (CFAL) was separated from lymphoblasts. The supernatant (SI) was obtained from the homogenized and centrifuged lymphoblasts Then, macrophage cultures contaning 0.2 X 10 a the sixth cells from lymphoma-bearing or hearthly mice were added to 10 µL of CFAL or S1, plus 5 µg of lipopolysaccharides (LPS)/mL, 40 U interferon-ç or a blend of both. Macrophages were incubated with CFAL or S1 prior to or after adding the activators to investigate whether any of the previously mentioned lymphoma fraction inhibited macrophage activation or whether they deactivated them. The effect of CFAL or S1 was estimated as the diminution of the amount of nitric ixide released by the experimental macrophage cultures with respect to controls (activated macrophages treated with none of the lymphoma fractions). Results. LPS, IFN-ç, and the LPS/ç blend activated macrophages from both lymphomabearing and healthy mice. None of the lymphoma fractions deactivated macrophages. CFAL, but not S1, inhibited the macrophage activation, i.e., the percentage of inhibition of nitric oxide releasing 76.7 percent in macrophages from healthy and lymphomabearing mice, respectively. In addition, CFAL was unable to inhibit macrophage-activation effect of IFN-ç or the LPS/IFN-ç blend. Conclusions. Mouse L5178Y Lymphoma releases a factor that in vitro inhibits the macrophage activation induced by LPS, but not by IFN-ç controls