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1.
Environ Toxicol Chem ; 40(10): 2861-2873, 2021 10.
Article in English | MEDLINE | ID: mdl-34314524

ABSTRACT

The use of pesticides for plague control in agroecosystems generates a threat to wildlife and a major problem for human health. Pesticide compounds are also an important source of water and atmosphere contamination. Although insecticides are effective on their target organisms, they often affect organisms that are not their target. The aim of the present study was to research the effects of 3 types of neurotoxic insecticides-a pyrethroid (cypermethrin), a neonicotinoid (imidacloprid), and an organophosphate (chlorpyrifos)-on behavioral and physiological parameters of Pardosa saltans spider (Lycosidae). Our study analyzed for the first time the exploratory behavior of the spider mothers in the presence of these 3 insecticides on their egg-sacs and also on the ground. We also evaluated the oxidative stress effects on the juveniles hatched in the egg-sac protected by silk in relation to variations in detoxification enzymes (catalase, glutathione reductase, superoxide dismutase, glutathione-S-transferase, and glutathione peroxidase) and lipid peroxidation (reactive oxygen species [ROS]). The results show that these insecticides are repellents for mothers (cypermethrin is the most repellent), and maternal behavior is modified after detection of an insecticide on their egg-sac but mothers do not abandon their egg-sacs. These neurotoxic insecticides affect the juveniles inside their egg-sac. Cypermethrin and chlorpyrifos caused more oxidative stress in juveniles than did imidacloprid. The ROS generated by these insecticides seemed to be adequately eliminated by the juveniles' antioxidant systems. Environ Toxicol Chem 2021;40:2861-2873. © 2021 SETAC.


Subject(s)
Chlorpyrifos , Insecticides , Pesticides , Pyrethrins , Spiders , Animals , Chlorpyrifos/toxicity , Female , Glutathione Transferase/metabolism , Humans , Insecticides/toxicity , Mothers , Oxidative Stress , Pesticides/pharmacology , Pyrethrins/toxicity , Reactive Oxygen Species , Silk/pharmacology , Spiders/metabolism
2.
Pestic Biochem Physiol ; 165: 104559, 2020 May.
Article in English | MEDLINE | ID: mdl-32359558

ABSTRACT

Spiders are found among the most important predators of plague insects of numerous agricultural systems. They are the most numerous representatives of the Class Arachnid and are widely distributed in numerous ecosystems. Due to multiple variables, living beings are exposed to quantitative transitions of their energetic reserves, which affect their sensitivity before the different xenobiotics. In the present study we evaluate the effect of cypermethrin (pyrethroid) on different metabolic/energetic stages of the spider Polybetes pythagoricus (Sparassidae). We firstly studied LD50 of cypermethrin on young, males and, pre-vitellogenic and post-vitellogenic females. The activity of superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), glutathione-S-transferase (GST) and acetylcholinesterase (AChE) was analyzed. Results indicate that young have a higher caloric content compared to adults, females have a higher caloric content than males and vitellogenesis generates a great calory decrease in females. The LD50 was significantly lower in young (10%) (103 ng/g weight) in relation to the three models of adults (969-1108 ng/g weight). Vitellogenesis causes an increase of free radicals as a result of the different metabolic processes which manifest as an increase in the lipid peroxidation. Doses at the LD30 and LD40 levels of cypermethrin did not generate alterations in any of the enzymes analyzed in young, this fact may probably provoke an increase of lipid peroxidation (evaluated as a great MDA increase). The activity of the enzymes linked to oxidative stress was altered by this doses in the three adult models, the enzymatic activity CAT, GR, and GST was sex-dependent. Post-vitellogenic females showed a greater activity of CAT, SOD, GST and GR before the xenobiotics than pre-vitellogenic ones, probably as a consequence of metabolic stress generated during vitellogenesis.


Subject(s)
Pyrethrins , Spiders , Animals , Antioxidants , Catalase , Ecosystem , Female , Glutathione , Glutathione Peroxidase , Glutathione Transferase , Lipid Peroxidation , Male , Oxidative Stress , Superoxide Dismutase
3.
J Comp Physiol B ; 189(3-4): 335-350, 2019 08.
Article in English | MEDLINE | ID: mdl-30953127

ABSTRACT

Vitellogenesis represents one of the most vital processes of oviparous species during which various proteins, carbohydrates, and lipids are synthesized and stored inside the developing oocytes. Through analyzing protein changes in the midgut diverticula, hemolymph, and ovaries of females throughout the different vitellogenic stages of the spider Polybetes pythagoricus, we determined the origin of the different proteins involved in the formation of lipovitellins (LVs) along with the existence of a linkage between the hemocyanin and this vital process. An increase in the total protein content of the midgut diverticula, hemolymph, and ovary occurred throughout vitellogenesis followed by a decrease in those levels after laying. The presence of hemocyanin in egg and in LV2, as well as its accumulation in the ovary throughout the vitellogenesis process, was determined. Considering that all biologic processes depend on the correct structure and function of proteins, this study establishes, for the first time for the Order Araneae, the coexistence of three different origins of vitellogenesis-related proteins: one predominantly ovarian involving peptides of 120, 75, 46, and 30 kDa; another extraovarian one originated from the midgut diverticula and represented by a 170 kDa peptide, and a third hemolymphatic one, represented by the 67 kDa peptide.


Subject(s)
Gene Expression Regulation, Developmental/physiology , Spiders/physiology , Vitellogenesis/physiology , Animals , Egg Proteins/genetics , Egg Proteins/metabolism , Female , Lipoproteins/genetics , Lipoproteins/metabolism , Male , Proteins/metabolism , Reproduction/physiology
4.
Folia Neuropathol ; 53(1): 24-8, 2015.
Article in English | MEDLINE | ID: mdl-25909872

ABSTRACT

The MTHFR gene has been reported as a susceptibility locus for sporadic Parkinson's disease (sPD). The functional variant rs1801133 has been linked to hyperhomocysteinemia and dopaminergic cell death. Among different populations, Mexican-Mestizos (most present-day Mexicans) have the highest frequency of this variant. Therefore, we sought to determine a possible association of rs1801133 with SPD. In total, 356 individuals were included: 140 patients with PD, diagnosed according to the Queen Square Brain Bank criteria, and 216 neurologically healthy controls. Genotyping was performed using TaqMan probes for rs1801133 and real-time PCR. Logistic regression analysis with adjustment for smoking and gender was used to test for an association between genotype and SPD. The CC genotype was associated with SPD; exp() = 2.06; 95% CI: 1.101-3.873, p = 0.024. No association with age at onset, cognitive impairment or gender was found in our study group. Our data suggest an important role of MTHFR gene variants in SPD.


Subject(s)
Genetic Association Studies/methods , Genetic Variation/genetics , Methylenetetrahydrofolate Reductase (NADPH2)/genetics , Parkinson Disease/diagnosis , Parkinson Disease/genetics , Aged , Case-Control Studies , Female , Humans , Male , Mexico/epidemiology , Middle Aged , Parkinson Disease/epidemiology , Polymorphism, Single Nucleotide/genetics
5.
Environ Monit Assess ; 187(3): 65, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25647787

ABSTRACT

The effect of the organophosphate fenitrothion (FS) on the non-target freshwater prawn Palaemonetes argentinus was studied. Initially, the 96-h lethal concentration (LC50) of FS was determined in adult prawns. Inhibition of cholinesterase (ChE) in the muscle and hemolymph was assessed. Then, in the hepatopancreas, the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione-S-transferase (GST) were analyzed. Lipid peroxidation (LPO) was also determined in the hepatopancreas. The 96-h LC50 value was 1.12 µg/L. Hemolymph ChE activity showed a significant decrease in exposed prawns to FS compared to the control group, while no significant differences in the muscle were observed between groups (p < 0.05). FS caused a significant increase in the activity of antioxidant enzymes SOD, CAT, and GST compared to the control group (p < 0.02). By contrast, LPO levels were not affected by the pesticide (p < 0.05). These results indicate that P. argentinus is very sensitive to organophosphorus which alter biochemical parameters that are related to antioxidant status. Thus, these parameters could be used as biomarkers for assessing water pollution.


Subject(s)
Fenitrothion/toxicity , Water Pollutants, Chemical/toxicity , Animals , Biomarkers/metabolism , Catalase/metabolism , Cholinesterases/metabolism , Environmental Monitoring , Fresh Water , Glutathione Transferase/metabolism , Lipid Peroxidation/drug effects , Palaemonidae/drug effects , Superoxide Dismutase/metabolism , Toxicity Tests, Acute
7.
Neotrop Entomol ; 41(1): 32-41, 2012 Feb.
Article in English | MEDLINE | ID: mdl-23950007

ABSTRACT

The present study analyzed the drosophilid assemblages in different levels of urbanization in the city of Porto Alegre, Rio Grande do Sul, Brazil. Collections were carried out in 2008 in three different environments: a highly urbanized area-"Jardim Botânico," a forested area with intermediary urbanization-"Parque Gabriel Knijnik," and in a relatively well-preserved forested area, although threatened by the urban growth-"Morro Santana." In Jardim Botânico, 36 species belonging to four genera were found, with high abundance of exotic species as Drosophila simulans Sturtevant and Zaprionus indianus (Gupta). In Parque Gabriel Knijnik, 33 species that belonged to four genera were found, with higher abundances of native species belonging to the Drosophila tripunctata species group and Drosophila willistoni species subgroup, and lower abundance of exotic species. As for Morro Santana, 32 species and three genera were found, with higher abundances of native groups, low representativeness of exotic species, and absence of Zaprionus indianus. The analysis of the Jaccard index showed higher similarity in the species composition between samples collected in summer and autumn, and between samples collected in winter and spring. On the other hand, the Morisita index differentiated Jardim Botânico from the other two studied sites. Our results show that Morro Santana is an important area of native biodiversity, reinforcing, therefore, the inclusion of this area in the project for the creation of an ecological corridor as proposed by the Ministry of the Environment of Brazil.


Subject(s)
Drosophilidae , Animals , Brazil , Cities , Population Density , Seasons , Trees , Urbanization
8.
Comp Biochem Physiol B Biochem Mol Biol ; 155(2): 126-31, 2010 Feb.
Article in English | MEDLINE | ID: mdl-19879374

ABSTRACT

Lipovitellin (LV) is essential in crustacean eggs for embryo viability and development. Two LV were isolated from eggs of Macrobrachium borellii. corresponding to early (LVe ) and late (LVl) embryo developing stages. They differ in lipid composition but not in lipid/protein ratio or apoprotein composition. Structural information was obtained by fluorescence spectroscopy, far-UV circular dichroism, partial trypsinolysis and electron microscopy applied to LVe and LVl and two partially delipidated forms of LVe generated by phospholipase A2 (LVp) or Triton X-100 (LVt) treatment. All LV forms contained two apoprotein subunits of 94 and 112 kDa, being the 112k Da subunit more accessible to trypsinolysis in all. Only in LVp, different cleavage sites appeared. Secondary structure was similar in LVe and LVl, but LVp and LVt showed a small increase in beta-sheet at expense of alpha-helix. Electron microscopy revealed a spheroidal morphology in all LV and a decreased size in LVp. Delipidated LVs were more resistant to denaturation with guanidinium-HCl. Acrylamide quenching of tryptophan fluorescence was more efficient in delipidated LVs, probably due to apolipoprotein rearrangement, as reinforced by fluorescence anisotropy. It is concluded that LV stability, shape, and apoprotein conformation is not largely affected by the changes in lipid composition that take place during embryogenesis.


Subject(s)
Egg Proteins/chemistry , Lipids/analysis , Lipids/chemistry , Palaemonidae/chemistry , Animals , Circular Dichroism , Egg Proteins/metabolism , Electrophoresis, Polyacrylamide Gel , Embryo, Nonmammalian/metabolism , Embryo, Nonmammalian/physiology , Female , Guanidine/pharmacology , Lipid Metabolism , Microscopy, Electron , Octoxynol/metabolism , Palaemonidae/embryology , Phospholipases A2/metabolism , Protein Denaturation/drug effects , Protein Stability , Solvents/chemistry , Spectrophotometry, Ultraviolet , Trypsin/metabolism
9.
Lipids ; 44(4): 337-44, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19130111

ABSTRACT

Mammals express four isoforms of glycerol-3-phosphate acyltransferase (GPAT). The mitochondrial isoform GPAT1 may have been the acyltransferase that appeared first in evolution. The hepatopancreas of the crustacean Macrobrachium borellii has a high capacity for triacylglycerol (TAG) biosynthesis and storage. In order to understand the mechanism of glycerolipid biosynthesis in M. borellii, we investigated its hepatopancreas GPAT activity. In hepatopancreas mitochondria, we identified a GPAT activity with characteristics similar to those of mammalian GPAT1. The activity was resistant to inactivation by SH-reactive N-ethylmaleimide, it was activated by polymyxin-B, and its preferred substrate was palmitoyl-CoA. The reaction products were similar to those of mammalian GPAT1. A 70-kDa protein band immunoreacted with an anti-rat liver GPAT1 antibody. Surprisingly, we did not detect high GPAT specific activity in hepatopancreas microsomes. GPAT activity in microsomes was consistent with mitochondrial contamination, and its properties were similar to those of the mitochondrial activity. In microsomes, TAG synthesis was not dependent on the presence of glycerol-3 phosphate as a substrate, and the addition of monoacylglycerol as a substrate increased TAG synthesis 2-fold. We conclude that in M. borellii the de novo triacylglycerol biosynthetic pathway can be completed in the mitochondria. In contrast, TAG synthesis in the ER may function via the monoacylglycerol pathway.


Subject(s)
Glycerol-3-Phosphate O-Acyltransferase/metabolism , Hepatopancreas/enzymology , Mitochondria, Liver/enzymology , Triglycerides/biosynthesis , Animals , Electrophoresis, Polyacrylamide Gel , Esterification , Microsomes, Liver/metabolism , Palaemonidae
10.
Article in English | MEDLINE | ID: mdl-17030141

ABSTRACT

In oviparous species, proteins and lipids are found in the vitellus forming lipoproteins called lipovitellins. They are an important energy source for embryos development and larvae growth and survival. We have previously isolated and partially characterized the sole egg cytosolic lipovitellin from the freshwater shrimp Macrobrachium borellii. It is a native protein of 440 kDa, composed of two subunits of 94 and 112 kDa. In the present work we studied size, shape and structure of M. borellii lipovitellin using electron microscopy, crosslinking reagents, MALDI-TOF, circular dichroism, fluorescence and partial proteolysis. The results showed that lipovitellin has a quasi spherical morphology with an estimated diameter of 18.5+/-3.5 nm. It appears to be composed of two subunits of 94 kDa, and one of 112 kDa. The larger subunit is more susceptible to trypsinolysis, indicating that it is less compactly folded and/or more exposed to the aqueous medium than the 94 kDa subunits. The hetero-trimer is held together by non-covalent interactions. Peptide mass fingerprinting by MALDI-TOF, produced 42 polypeptides matching to a vitellogenin of a related species (Macrobrachium rosenbergii). Circular dichroism indicated that this protein contains 35.7% alpha-helix, 16.6% beta-sheet and 20% turns. Tryptophan fluorescence emission, at a maximum of 334 nm, indicated that the environment polarity of these aromatic residues is similar to that of other crustacean lipoproteins.


Subject(s)
Egg Proteins/analysis , Palaemonidae/chemistry , Amino Acid Sequence , Animals , Circular Dichroism , Egg Proteins/metabolism , Electrophoresis, Polyacrylamide Gel , Female , Microscopy, Electron , Molecular Sequence Data , Ovum/chemistry , Palaemonidae/genetics , Spectrometry, Fluorescence , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Vitellogenins/genetics
11.
Lipids ; 37(7): 673-9, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12216838

ABSTRACT

The effect of the liposoluble organophosphorus insecticide fenitrothion (FS) on lipid packing and rotation of two crustacean plasma HDL was investigated. These lipoproteins, HDL-1 and HDL-2, differed in their lipid composition, but their lipid/protein ratios were similar. The rotational behavior of the fluorescent probes 1,6-diphenyl-1,3,5-hexatriene (DPH) and 3-(p-(6-phenyl)-1,3,5-hexatrienyl) phenylpropionic acid (DPH-PA) was used to obtain information about the lipid dynamics in the outer and inner regions, respectively, of the lipid phase of the lipoproteins. Fluorescent steady-state anisotropy (r(s)), lifetime (tau), rotational correlation time (tau(r)), and the limiting anisotropy (r(infinity)) of these probes were measured in the lipoproteins exposed to different concentrations of FS in vitro. The results showed the penetration of FS into both plasma lipoproteins, altering the lipid dynamics of the inner as well as the outer regions. The overall effect of the insecticide was to induce an increase in the lipid order in a concentration-dependent fashion. DPH and DPH-PA fluorescence-lifetime shortening indicated that FS increased the polarity of the probe environment, suggesting an enhanced water penetration into the lipoprotein lipid phase, may be due to the induction of failures in the lipid packing. Even in the absence of FS, a higher ordering of the lipid phase was found in HDL-2 compared to HDL-1, a fact that might be attributed to a higher percentage of sphingomyelin in HDL-2.


Subject(s)
Crustacea/chemistry , Crustacea/drug effects , Fenitrothion/pharmacology , Insecticides/pharmacology , Lipoproteins/chemistry , Lipoproteins/drug effects , Animals , Chemical Phenomena , Chemistry, Physical , Diphenylhexatriene , Female , Fluorescence Polarization , Lipoproteins/blood , Lipoproteins/isolation & purification , Male , Palaemonidae/chemistry , Palaemonidae/drug effects , Palmitic Acid/metabolism , Temperature
12.
Environ Mol Mutagen ; 33(1): 86-90, 1999.
Article in English | MEDLINE | ID: mdl-10037327

ABSTRACT

The effect of pig monocytes (MNs) on the baseline frequency of sister chromatid exchanges (SCEs) and cell-cycle progression of pig lymphocytes was studied in plasma leukocyte (PLCs) and whole blood leukocyte cultures (WBCs). No variation in SCE frequency was observed between control WBC and PLC, nor did the addition of pig MNs to PLCs modify the baseline frequency of SCEs. Cell proliferation was slower in PLCs than in WBCs. Variations in cell-cycle progression of pig lymphocytes from PLC were observed both in the absence and presence of adherent cells in the culture. In MN-free cultures, lymphocytes proliferated foster than in parallel PLC cultures. However, when MNs were seeded into the cultures, cell-cycle progression gradually slowed as a function of the concentration of adherent cells present in the cultures. This finding shows that pig MNs modulate the in vitro cell-cycle progression of pig lymphocytes in a dose-dependent manner and that the low baseline SCE frequency of pig lymphocytes is independent of the presence or absence of MNs in the culture.


Subject(s)
Cell Cycle/physiology , Lymphocytes/physiology , Monocytes/physiology , Sister Chromatid Exchange/physiology , Animals , Cell Adhesion , Cell Division , Cells, Cultured , Coculture Techniques , Leukocyte Count , Lymphocyte Count , Lymphocytes/cytology , Male , Swine
13.
J Int Med Res ; 24(4): 369-75, 1996.
Article in English | MEDLINE | ID: mdl-8854292

ABSTRACT

The efficacy of delivering medicines by metered-dose inhaler (MDI) is well established, and the patient's technique with MDIs is related directly to achieving the desired clinical outcome. The present study was designed to assess and improve MDI technique by using a Vitalograph Aerosol Inhalation Monitor (VAIM) in an airways disease education programme. Baseline measurements were made immediately prior to educational intervention incorporating feedback from a VAIM unit. At 6 weeks' follow-up, MDI technique was found to have regressed to the sub-optimal measures recorded at baseline prior to educational intervention. However, patients reported a significant improvement in physical function between baseline and follow-up as measured by the Rand 36-Item Health Survey (SF-36), Version 1.0. The results reinforce the need for a longitudinal educational programme for patients prescribed medications delivered by MDI. The VAIM unit provided health educators and patients with both a visual and a quantitative assessment of patients' MDI technique, and was thus of positive value as part of the intervention process.


Subject(s)
Asthma/drug therapy , Lung Diseases, Obstructive/drug therapy , Nebulizers and Vaporizers , Patient Education as Topic , Quality of Life , Adult , Anti-Asthmatic Agents/administration & dosage , Bronchodilator Agents/administration & dosage , Female , Humans , Male , Middle Aged
14.
Rev. colomb. cir ; 8(1): 55-60, mar. 1993. ilus
Article in Spanish | LILACS | ID: lil-328649

ABSTRACT

Se presenta el caso de un paciente de sexo masculino, de 63 años de edad con cuadro de ictericia obstructiva, con diagnostico de tumor de Klatskin, en quien se intenta realizar una derivación radiologica interna, sin exito. En cirugia se practico reseccion del tumor y se complementó con un procedimiento de Chen. Durante el primer mes posoperatorio el paciente reingresó por un cuadro de ictericia obstructiva recurrente. Se evidencio radiográficamente la obstruccion de las anastomosis bilioentericas, para cuyo tratamiento se practico colocacion selectiva de dos protesis de Gianturco, por medio del asa yeyunal subcutánea, construida durante el procedimiento quirurgico. El paciente presento mejoria del cuadro recurrente. Se realiza una revision de la literatura y se comentan los nuevos enfoques diagnosticos y terapeuticos disponibles. Se analiza la controversia entre el procedimiento paliativo frente a la posibilidad de un tratamiento quirurgico radical y se hace enfasis en la complementación que tiene la conducta seguida.


Subject(s)
Klatskin Tumor
15.
Rev. colomb. cir ; 5(3): 159-163, dic. 1990. ilus
Article in Spanish | LILACS | ID: lil-328749

ABSTRACT

El tratamiento quirurgico de las metastasis pulmonares constituye un avance relativamente reciente de la cirugia oncologica y parece justificarse plenamente a la luz de los resultados publicados en la literatura. Sin embargo, es indispensable efectuar una seleccion minuciosa de los pacientes si se quiere obtener resultados satisfactorios en terminos de paliacion y, en algunos casos, de curacion. Los mejores resultados se han obtenido en aquellos tumores que se diseminan por via hemática en forma primaria al pulmon. No obstante, deben tenerse en cuenta otros factores como el tipo histologico y la localizacion del tumor, el control del tumor primario y el intervalo de tiempo transcurrido entre dicho control y la aparicion de la enfermedad metastásica. Tambien se revisan en este articulo los aspectos relacionados con la via de acceso y la tecnica quirurgica.


Subject(s)
Lung Neoplasms , Neoplasm Metastasis , Thoracotomy
16.
Gastroenterology ; 99(3): 854-6, 1990 Sep.
Article in English | MEDLINE | ID: mdl-2116345

ABSTRACT

The unique case of severe chronic cholestasis with paucity of bile ducts accompanied by pure red cell aplasia and the Stevens-Johnson syndrome in a 35-year-old woman after ampicillin ingestion is presented. The patient improved gradually and is asymptomatic 4 years later. Sequential histological and clinical follow-up substantiate the course of her disease.


Subject(s)
Ampicillin/adverse effects , Bile Duct Diseases/chemically induced , Cholestasis/chemically induced , Drug Hypersensitivity/etiology , Red-Cell Aplasia, Pure/chemically induced , Stevens-Johnson Syndrome/chemically induced , Adult , Chronic Disease , Female , Humans
17.
Article in English | MEDLINE | ID: mdl-2313560

ABSTRACT

From October 1985 to November 1987, a sample of 294 Colombian homosexual men volunteered to answer a questionnaire on sexual practices and consented to HIV-1 testing. Testing for HIV-1 was performed using an ELISA and those positive were confirmed with envelope- and core-specific ELISAs. Statistical methods for data analysis included Mantel-Haenszel methods on contingency tables. The overall seropositivity rate was 21.1%. Subjects who reported a receptive role (either as predominantly receptive or as mixed receptive-insertive intercourse) had a seropositivity rate of 23.7%, which was significantly higher than the 10.3% found in those reporting predominantly insertive intercourse (RR = 2.30, 95% C.I. = 1.16-4.57). For subjects reporting receptive intercourse, sexual contact with foreign visitors was a significant risk factor for HIV-1 infection (RR = 1.84, 95% C.I. = 1.13-3.00). Factors of borderline significance included having had more than ten homosexual partners in the preceding year (RR = 1.53) and a history of international travel (RR = 1.43). These associations did not hold for those reporting predominantly insertive intercourse. The data indicate the need to monitor the spread of HIV-1 at the international level and provide information on subgroups of high transmission rates.


Subject(s)
HIV Seroprevalence , HIV-1 , Homosexuality , Sexual Behavior , Travel , Adult , Colombia/epidemiology , False Positive Reactions , Female , Humans , Male , Mass Screening/methods , Risk Factors , Seroepidemiologic Studies
18.
Am J Clin Pathol ; 88(4): 483-5, 1987 Oct.
Article in English | MEDLINE | ID: mdl-2821794

ABSTRACT

Anti-Tac is a monoclonal antibody that appears to recognize the interleukin-2 receptor. With the use of a frozen-section immunoperoxidase technic, a large series of non-Hodgkin's lymphomas were investigated for the presence of Tac-antigen on neoplastic cells. Approximately one-fourth of cases expressed the Tac antigen, including 27% of B-lineage lymphomas, 6% of the T-lineage lymphomas, and three of four cases of Ki-1-expressing lymphoma. The B-lineage lymphomas with the highest incidence of Tac antigen expression were the large cell lymphomas, both diffuse and follicular, where about one-half of cases expressed the Tac antigen. All major categories of lymphoma expressed Tac except plasma-cytoma/myeloma, small noncleaved cell (Burkitt's and non-Burkitt's), and lymphoblastic malignancies.


Subject(s)
Antigens, Surface/analysis , Lymphoma, Non-Hodgkin/immunology , Antibodies, Monoclonal/immunology , B-Lymphocytes/immunology , Humans , Immunoenzyme Techniques , T-Lymphocytes/immunology , Tumor Necrosis Factor Receptor Superfamily, Member 7
19.
Am J Clin Pathol ; 88(4): 486-90, 1987 Oct.
Article in English | MEDLINE | ID: mdl-3310610

ABSTRACT

The Leu-8 antigen is found on the surface of many hematologic cells, including many T- and B-lymphocytes. With the use of a frozen-section immunoperoxidase technic, 152 B-cell non-Hodgkin's lymphomas were examined for Leu-8 expression. Of these lymphomas, 53% expressed Leu-8. Subclassification of the lymphomas with the use of the International Working Formulation showed that most small lymphocytic, intermediate lymphocytic, and diffuse large cell lymphomas and about half of diffuse small cleaved, diffuse mixed, and follicular lymphomas expressed Leu-8. In contrast, all 17 cases of small noncleaved cell (Burkitt's) lymphoma and 9 of 10 cases of multiple myeloma/plasmacytoma were Leu-8 negative. These results indicate that Leu-8 is expressed on a wide variety of B-cell lymphomas and that differences in Leu-8 expression may be useful in the diagnostic separation of small lymphocytic lymphoma with plasmacytoid features from multiple myeloma/plasmacytoma, and diffuse large cell lymphoma from Burkitt's lymphoma.


Subject(s)
Antigens, Differentiation, T-Lymphocyte/analysis , Antigens, Neoplasm/analysis , B-Lymphocytes/immunology , Lymphoma, Non-Hodgkin/immunology , Antibodies, Monoclonal/immunology , Humans , Immunoenzyme Techniques
20.
Am J Clin Pathol ; 87(4): 470-7, 1987 Apr.
Article in English | MEDLINE | ID: mdl-3103419

ABSTRACT

A quantitation method for lymphocyte subsets in immunoperoxidase-stained frozen tissue sections was compared with flow cytometry in 23 cases of non-Hodgkin's lymphoma. Close correlations were obtained, demonstrating the accuracy of the technic. Weak intensity of fluorescence and fragility of the tumor cells during the fluorescence-activated cell sorter (FACS) analyses were the most likely explanations for a number of the discrepancies observed. The tissue quantitation method was precise, particularly at low values, where it was better than the FACS. A simpler and faster estimation method employing categories within 10 percentage units was also tested in this study; this method correlated as well with the FACS as the quantitation method and gave the best interobserver correlations.


Subject(s)
Cell Count/methods , Cell Separation , Flow Cytometry , Immunoenzyme Techniques , Lymphocytes/cytology , Antigens, Differentiation, T-Lymphocyte , Antigens, Surface/analysis , B-Lymphocytes/classification , Frozen Sections , Humans , Lymphocytes/immunology , Lymphoma, Non-Hodgkin/pathology , Retrospective Studies , T-Lymphocytes/classification
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