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1.
Int J Tuberc Lung Dis ; 25(11): 939-944, 2021 11 01.
Article in English | MEDLINE | ID: mdl-34686237

ABSTRACT

BACKGROUND: Extrapulmonary TB (EPTB) comprises approximately 15-20% of TB cases worldwide, and its diagnosis is difficult. The sensitivity of Xpert® MTB/RIF (Xpert) in the diagnosis of EPTB is low on account of its paucibacillary nature. Xpert® MTB/RIF Ultra (Ultra) was developed to improve sensitivity.OBJECTIVE: To compare the sensitivity of Ultra test with that of Xpert against MGIT™ (Mycobacteria Growth Indicator Tube) culture and a composite reference standard (CRS).METHODS: We recruited consecutive treatment-naïve patients with suspected EPTB. Demographic information, clinical and relevant laboratory data were collected.RESULTS: From January 2019 to November 2019, 210 patients provided 250 samples. Against MGIT culture, the sensitivity of Ultra was significantly higher than Xpert (72% vs. 51.1%; P = 0.04), the specificity was lower (87.8% vs. 95.1%). Against the CRS also, the sensitivity of Ultra was significantly higher than Xpert (45.4% vs. 25.2%; P = 0.002); however, the specificities were similar (98.2% vs. 99.1%). The trend towards higher sensitivity of Ultra compared to Xpert was seen in most of the individual samples. The sensitivities against MGIT and CRS were as follows: lymph node (68.1% vs. 31.8%; P = 0.01) and (59.5% vs. 23.8%; P = 0.001), pleural biopsy (80.0% on both; P = NS) and (53.8% vs. 46.2%; P = NS) and pleural fluid (66.7% vs. 50%; P = NS) and (22.5% vs. 9.6%; P = NS), respectively.CONCLUSIONS: Xpert Ultra showed a significantly higher sensitivity in diagnosing EPTB than Xpert.


Subject(s)
Antibiotics, Antitubercular , Mycobacterium tuberculosis , Tuberculosis , Antibiotics, Antitubercular/therapeutic use , Humans , Rifampin , Sensitivity and Specificity , Tuberculosis/diagnosis , Tuberculosis/drug therapy
2.
Community Dent Health ; 34(1): 37-40, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28561556

ABSTRACT

OBJECTIVE: To assess the relationship between sense of coherence (SOC) and oral health-related quality of life (OHRQoL) among children aged one to three years. PARTICIPANTS: A cross-sectional study was conducted with 276 mother-child pairs randomly selected from the city of Diamantina, Brazil. METHOD: Information was obtained on socio-demographic factors. The short version of Antonovsky's sense of coherence scale (SOC 13) and the Early Childhood Oral Health Impact Scale (ECOHIS) were administered. The children were examined for dental caries. Statistical analysis involved descriptive statistics, the calculation of Spearman's correlation coefficients and adjusted Poisson regression models. RESULTS: SOC was significantly associated with the child's OHRQoL in the multivariate analysis. Children of mothers with high SOC (PR 0.96; 95%CI 0.93,0.98; p=0.045) had a lower prevalence of a negative impact on OHRQoL. Children with severe dental caries had a greater prevalence of a negative impact on OHRQoL (PR 2.53; 95%CI 1.77,3.62; p⟨0.001). CONCLUSIONS: Maternal SOC could be a psychosocial determinant of the OHRQoL of children aged one to three years. Severe dental caries was associated with poorer quality of life.


Subject(s)
Mothers/psychology , Oral Health , Quality of Life , Sense of Coherence , Brazil , Child, Preschool , Cross-Sectional Studies , Dental Caries/epidemiology , Humans , Infant
3.
Genet Mol Res ; 16(2)2017 Apr 20.
Article in English | MEDLINE | ID: mdl-28437553

ABSTRACT

In Brazil, cultivation of hybrid plants comprise near 40% of the area grown with vegetables. For Capsicum, hybrids of bell and chili peppers have already exceeded 50% and over 25% of all are commercialized seeds. This study aimed to evaluate new pepper hybrids in two environments, Cáceres, MT, and Campos dos Goytacazes, RJ, Brazil. Nine experimental hybrids of C. baccatum var. pendulum were tested and trials were performed in a randomized block design, with three replications and eight plants per plot. In each environment, plants were assessed for canopy diameter, plant height, number of fruit per plant, mean fruit mass per plant, fruit length and diameter, pulp thickness, and content of soluble solids. Seven of the eight traits have differed significantly due to environment variation. Furthermore, genotype and environment interaction was highly significant for number of fruit per plant, mean fruit mass per plant, fruit length, and fruit diameter. Choosing a hybrid to be grown in one of the studied locations must be in accordance with the sought characteristics since there is a complex interaction for some studied traits.


Subject(s)
Capsicum/genetics , Gene-Environment Interaction , Hybridization, Genetic , Capsicum/growth & development , Fruit/genetics , Fruit/growth & development , Quantitative Trait, Heritable
4.
Evol Comput ; 24(4): 637-666, 2016.
Article in English | MEDLINE | ID: mdl-27258842

ABSTRACT

This article presents an Evolution Strategy (ES)--based algorithm, designed to self-adapt its mutation operators, guiding the search into the solution space using a Self-Adaptive Reduced Variable Neighborhood Search procedure. In view of the specific local search operators for each individual, the proposed population-based approach also fits into the context of the Memetic Algorithms. The proposed variant uses the Greedy Randomized Adaptive Search Procedure with different greedy parameters for generating its initial population, providing an interesting exploration-exploitation balance. To validate the proposal, this framework is applied to solve three different [Formula: see text]-Hard combinatorial optimization problems: an Open-Pit-Mining Operational Planning Problem with dynamic allocation of trucks, an Unrelated Parallel Machine Scheduling Problem with Setup Times, and the calibration of a hybrid fuzzy model for Short-Term Load Forecasting. Computational results point out the convergence of the proposed model and highlight its ability in combining the application of move operations from distinct neighborhood structures along the optimization. The results gathered and reported in this article represent a collective evidence of the performance of the method in challenging combinatorial optimization problems from different application domains. The proposed evolution strategy demonstrates an ability of adapting the strength of the mutation disturbance during the generations of its evolution process. The effectiveness of the proposal motivates the application of this novel evolutionary framework for solving other combinatorial optimization problems.


Subject(s)
Algorithms , Biological Evolution , Computer Heuristics , Computer Simulation , Humans , Machine Learning , Mining , Mutation , Personnel Staffing and Scheduling
5.
Hum Exp Toxicol ; 35(9): 958-65, 2016 Sep.
Article in English | MEDLINE | ID: mdl-26500220

ABSTRACT

Vigabatrin (VGB) is an antiepileptic drug thatincreases brain γ-aminobutyric acid (GABA) levels through irreversible inhibition of GABA transaminase. The aim of this study was to evaluate neurotoxicological effects of VGB measuring motor activity and genotoxic and mutagenic effects after a single and repeated administration. Male Wistar rats received saline, VGB 50, 100, or 250 mg/kg by gavage for acute and subchronic (14 days) treatments and evaluated in the rotarod task. Genotoxicity was evaluated using the alkaline version of the comet assay in samples of blood, liver, hippocampus, and brain cortex after both treatments. Mutagenicity was evaluated using the micronucleus test in bone marrow of the same animals that received subchronic treatment. The groups treated with VGB showed similar performance in rotarod compared with the saline group. Regarding the acute treatment, it was observed that only higher VGB doses induced DNA damage in blood and hippocampus. After the subchronic treatment, VGB did not show genotoxic or mutagenic effects. In brief, VGB did not impair motor activities in rats after acute and subchronic treatments. It showed a repairable genotoxic potential in the central nervous system since genotoxicity was observed in the acute treatment group.


Subject(s)
4-Aminobutyrate Transaminase/antagonists & inhibitors , Anticonvulsants/toxicity , DNA Damage , Micronuclei, Chromosome-Defective/chemically induced , Vigabatrin/toxicity , Animals , Cerebral Cortex/drug effects , Cerebral Cortex/enzymology , Cerebral Cortex/pathology , Comet Assay , Dose-Response Relationship, Drug , Hippocampus/drug effects , Hippocampus/enzymology , Hippocampus/pathology , Liver/drug effects , Liver/enzymology , Liver/pathology , Male , Micronucleus Tests , Motor Activity/drug effects , Organ Specificity , Rats, Wistar , Rotarod Performance Test , Time Factors
6.
PLoS One ; 10(11): e0142982, 2015.
Article in English | MEDLINE | ID: mdl-26599324

ABSTRACT

UNLABELLED: The prevalence of hypertension in childhood is increasing, and investigation of its distribution is important for planning timely interventions. This study assessed the prevalence of high blood pressure (HBP) and associated factors in students between 9 and 11 years of age enrolled in public and private schools in Maceió, Brazil. A cross-sectional study was performed in a probabilistic sample of students (10.3 ± 0.5 years). The students were selected from a systematic sampling of 80 schools (40 public and 40 private). To maintain similar proportions of students existing in public and private schools in Maceió, 21 and 14 students were randomly selected from each public and private school, respectively. The prevalence ratio (PR) was estimated using Poisson regression. A total of 1,338 students were evaluated (800 from public schools and 538 from private schools). No differences were observed between school types in terms of student age and gender (p > 0.05). The prevalence of obesity (19.9% vs. 9.0%; PR = 2.2; 95% CI = 1.67-2.92) and hypertension (21.2% vs. 11.4%; PR = 1.86; 95% CI = 1.45-2.40) were higher in private schools. The association between high blood pressure and type of school (public or private) remained statistically significant even after adjustment for obesity (PR = 1.53; 95% CI = 1.19-1.97). IN CONCLUSION: (a) students from private schools have higher socioeconomic status, BMI, and HBP prevalence compared to those of public school; (b) among the evaluated students, the prevalence of obesity only partially explained the higher prevalence of high blood pressure among students from private schools. Other factors related to lifestyle of children from private schools may explain the higher prevalence of HBP. This results show the need to implement measures to promote healthy lifestyles in the school environment, since children with HBP are more likely to become hypertensive adults. Therefore, early detection and intervention in children with HBP is an important action for the prevention of hypertension in adulthood.


Subject(s)
Hypertension/epidemiology , Schools/statistics & numerical data , Students/statistics & numerical data , Brazil/epidemiology , Child , Demography , Female , Health , Humans , Male , Prevalence , Socioeconomic Factors
7.
Toxicon ; 83: 15-21, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24560880

ABSTRACT

Mature Ts1, the main neurotoxin from Tityus serrulatus venom, has its C-terminal Cys amidated, while the isolated isoform of Ts1, named Ts1-G, keeps the non-amidated Gly residue at the C-terminal region, allowing the study of the comparative functional importance of amidation at the C-terminal between these two native toxins. Voltage dependent sodium current measurements showed that the affinity of Ts1-G for sodium channels is smaller than that of the mature Ts1, confirming the important role played by the C-terminal amidation in determining Ts1 activity.


Subject(s)
Arthropod Proteins/chemistry , Insect Proteins/chemistry , Neurotoxins/chemistry , Scorpion Venoms/chemistry , Amino Acid Sequence , Animals , Arthropod Proteins/isolation & purification , Arthropod Proteins/toxicity , Blood Glucose/drug effects , Chemical Fractionation , Insect Proteins/isolation & purification , Insect Proteins/toxicity , Male , Mice, Inbred Strains , Molecular Sequence Data , Neurotoxins/isolation & purification , Neurotoxins/toxicity , Protein Isoforms/chemistry , Protein Isoforms/isolation & purification , Protein Isoforms/toxicity , Scorpion Venoms/isolation & purification , Scorpion Venoms/toxicity , Scorpions , Sequence Alignment
8.
Neotrop Entomol ; 40(3): 393-7, 2011.
Article in English | MEDLINE | ID: mdl-21710036

ABSTRACT

Myiases are infestations with dipteran larvae in both necrosed and living tissues, the food source of these insects. These illnesses occur in warm humid climates, and are most frequent in developing countries. We assessed the epidemiological aspects and the influence of climate on the occurrence of myiases and the bioagents in patients admitted to the federal Hospital do Andaraí in Rio de Janeiro from February 2007 to 2008. The influence of abiotic factors (temperature, humidity, and rainfall) on the incidence of myiases was investigated by using the Pearson's correlation test. Of the 40 patients studied, the prevalence of myiases was higher in adults, particularly in the 40 to 65 year-old (37.5%) African descent males (57.5%). Most of the injuries were caused by trauma (62.5%). Some patients made use of licit (50%) and illicit drugs (17.2%). The occurrence of myiases was not affected by the abiotic factors investigated. The cases reported here were treated in only one hospital, indicating that the disease is relatively common. The most frequent bioagent was Cochliomyia hominivorax (Coquerel), but Cochliomyia macellaria (Fabricius), Chrysomya albiceps (Wiedemann) and Dermatobia hominis (Wiedemann) (Diptera: Calliphoridae) were also detected causing myiases. Chrysomya albiceps is an exotic etiologic agent of myiases.


Subject(s)
Myiasis/epidemiology , Adolescent , Adult , Aged , Brazil , Child , Child, Preschool , Female , Hospitals , Humans , Infant , Male , Middle Aged , Prevalence , Young Adult
9.
Phytomedicine ; 18(10): 896-901, 2011 Jul 15.
Article in English | MEDLINE | ID: mdl-21420842

ABSTRACT

It is known that (-)-linalool is a competitive antagonist of NMDA receptors, which play a key role in the learning and memory processes; however, only a few studies have reported a possible interference of (-)-linalool in memory. The purpose of this study was to investigate the (-)-linalool effects on acquisition of short- and long-term memories through the objects recognition task, inhibitory avoidance test and habituation to a novel environment. Furthermore, the open field test was used to investigate the interference of (-)-linalool in motivation, locomotion and exploration by animals. Wistar male adult rats received an intraperitoneal injection (i.p.) of saline (NaCl 0.9%), tween 5% or (-)-linalool (50 or 100 mg/kg) before training in the tasks; MK-801 (0.1 mg/kg), a glutamate antagonist, was used as positive control. Short-term (STM) and long-term (LTM) memories were tested 1.5 and 24 h after training, respectively, in the inhibitory avoidance and recognition objects. The results suggested that (-)-linalool (as 50- and 100-mg/kg doses) impaired LTM acquisition, but not STM acquisition, in the object recognition task. In the inhibitory avoidance test, animals receiving linalool (both doses) showed impairment in acquisition of both memories measured. In the open field test, the animals that received (-)-linalool showed no significant difference in the crossings and latency to start the locomotion in any of the doses tested, although (-)-linalool 100 mg/kg reduced rearing behavior. When re-exposed to open field 24 h after training, the rats that received (-)-linalool 100mg/kg showed no habituation. Taken together, these data suggested that (-)-linalool was able to impair the acquisition of memory in rats, which can be associated to (-)-linalool antagonist capacity as regards NMDA glutamatergic receptors, since other glutamate antagonists also seem to affect memory.


Subject(s)
Avoidance Learning/drug effects , Habituation, Psychophysiologic/drug effects , Memory/drug effects , Monoterpenes/pharmacology , Acyclic Monoterpenes , Analysis of Variance , Animals , Dizocilpine Maleate/pharmacology , Inhibition, Psychological , Male , Monoterpenes/administration & dosage , Plant Preparations/pharmacology , Rats , Rats, Wistar , Receptors, N-Methyl-D-Aspartate/antagonists & inhibitors
10.
J Med Entomol ; 47(3): 487-90, 2010 May.
Article in English | MEDLINE | ID: mdl-20496599

ABSTRACT

We report a rare case of myiasis caused simultaneously by three dipterous species. A 54 yr-old indigent patient was admitted to Andaraí Hospital with painful eruptions on the scalp. The parieto-occipital sulcus showed two lesions caused by scratching associated with deep, odoriferous and exudative pediculosis. Larvae removed with the help of forceps and vaseline produced 153 adults, identified in the laboratory as 114 specimens of Chrysomya megacephala (F., 1794), 38 of Sarcophaga (Liopygia) ruficornis (F., 1794), and one of Musca domestica (L., 1758).


Subject(s)
Diptera/pathogenicity , Exudates and Transudates/metabolism , Houseflies/pathogenicity , Myiasis/parasitology , Scalp/parasitology , Animals , Awareness , Exudates and Transudates/parasitology , Humans , Hygiene , Larva/growth & development , Male , Middle Aged
11.
Braz J Biol ; 70(1): 55-63, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20231960

ABSTRACT

Samples were collected every month in three different sites of the Reserva Biológica do Tinguá, Brazil: site A was located on the border of the forest and sites B and C were located 1,000 and 500 m, respectively, towards the forest interior. The objective was to determine edge effects on a fragment of the Atlantic Forest. The greatest species richness was observed in sites A and B (23 species), compared with site C (16 species). Site A showed the greatest abundance and constancy, independent of the degree of synanthropy. Asynanthropic species were more abundant and constant in sites B and C. Site B showed the greatest diversity; and sites A and B showed the greatest similarity of populations. There was no significant correlation between Calliphoridae richness and canopy openness except in site C. Richness and abundance were positively correlated with subwood density, except for richness in site B.


Subject(s)
Biodiversity , Diptera/classification , Trees , Animals , Brazil , Ecosystem , Population Density , Seasons
12.
Insect Mol Biol ; 19 Suppl 1: 137-46, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20167024

ABSTRACT

Hexamerins and prophenoloxidases (PPOs) proteins are members of the arthropod-haemocyanin superfamily. In contrast to haemocyanin and PPO, hexamerins do not bind oxygen, but mainly play a role as storage proteins that supply amino acids for insect metamorphosis. We identified seven genes encoding hexamerins, three encoding PPOs, and one hexamerin pseudogene in the genome of the parasitoid wasp Nasonia vitripennis. A phylogenetic analysis of hexamerins and PPOs from this wasp and related proteins from other insect orders suggests an essentially order-specific radiation of hexamerins. Temporal and spatial transcriptional profiles of N. vitripennis hexamerins suggest that they have physiological functions other than metamorphosis, which are arguably coupled with its lifestyle.


Subject(s)
Catechol Oxidase/genetics , Enzyme Precursors/genetics , Evolution, Molecular , Insect Proteins/genetics , Insect Proteins/metabolism , Phylogeny , Wasps/genetics , Animals , Bayes Theorem , Computational Biology , DNA Primers/genetics , Gene Components , Gene Expression Profiling , Models, Genetic , Reverse Transcriptase Polymerase Chain Reaction , Species Specificity
13.
Horm Metab Res ; 42(4): 254-60, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20094971

ABSTRACT

Previous studies have shown that alterations in thyroid status may lead to changes in serum leptin and adiponectin, both in humans and rodents. The mechanisms, especially for adiponectin, are unclear. In the present study, we investigated the effect of triiodothyronine (T3) on the expression of adiponectin mRNA and the release of leptin and adiponectin by white adipose tissue (WAT) explants obtained from epididymal (visceral) or inguinal (subcutaneous) depots from normal rats. We also analyzed the effects of other known regulators of adiponectin and leptin release, such as rosiglitazone and dexamethasone. T3 acted directly at rat WAT explants in a depot-specific manner and in a unique fashion to each hormone. T3 was able to inhibit leptin release only by epididymal explants, and to reduce adiponectin mRNA expression only in inguinal explants. However, T3 was incapable of modifying adiponectin release by both explants. Additionally, rosiglitazone exhibited an inhibitory effect on adiponectin release by both WAT explants, even though adiponectin mRNA was importantly upregulated only in inguinal explants. Rosiglitazone acted as an inhibitor of leptin release by both studied fat depots, while only epididymal explants responded to the stimulatory effect of dexamethasone on leptin release. Therefore, the present model of isolated rat white adipose tissue explants highlights the fact that the regulation of hormonal production by white adipose tissue depends on the type of depot and its anatomical location. In this context, our results show for the first time a potential inhibitory effect of T3 on adiponectin mRNA expression specifically on WAT from a subcutaneous depot.


Subject(s)
Adiponectin/metabolism , Adipose Tissue, White/metabolism , Leptin/metabolism , Triiodothyronine/pharmacology , Adiponectin/genetics , Adipose Tissue, White/drug effects , Animals , Gene Expression Regulation/drug effects , Male , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rats , Rats, Wistar , Time Factors , Tissue Culture Techniques
14.
Cancer Gene Ther ; 16(7): 598-608, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19197326

ABSTRACT

DNA-hsp65, a DNA vaccine encoding the 65-kDa heat-shock protein of Mycobacterium leprae (Hsp65) is capable of inducing the reduction of established tumors in mouse models. We conducted a phase I clinical trial of DNA-hsp65 in patients with advanced head and neck carcinoma. In this article, we report on the vaccine's potential to induce immune responses to Hsp65 and to its human homologue, Hsp60, in these patients. Twenty-one patients with unresectable squamous cell carcinoma of the head and neck received three doses of 150, 400 or 600 microg naked DNA-hsp65 plasmid by ultrasound-guided intratumoral injection. Vaccination did not increase levels of circulating anti-hsp65 IgG or IgM antibody, or lead to detectable Hsp65-specific cell proliferation or interferon-gamma (IFN-gamma) production by blood mononuclear cells. Frequency of antigen-induced IL-10-producing cells increased after vaccination in 4 of 13 patients analyzed. Five patients showed disease stability or regression following immunization; however, we were unable to detect significant differences between these patients and those with disease progression using these parameters. There was also no increase in antibody or IFN-gamma responses to human Hsp60 in these patients. Our results suggest that although DNA-hsp65 was able to induce some degree of immunostimulation with no evidence of pathological autoimmunity, we were unable to differentiate between patients with different clinical outcomes based on the parameters measured. Future studies should focus on characterizing more reliable correlations between immune response parameters and clinical outcome that may be used as predictors of vaccine success in immunosuppressed individuals.


Subject(s)
Cancer Vaccines/therapeutic use , Carcinoma, Squamous Cell/therapy , Head and Neck Neoplasms/therapy , Heat-Shock Proteins/immunology , Immunotherapy/methods , Vaccines, DNA/immunology , Adult , Aged , Antibody Formation/immunology , Cancer Vaccines/immunology , Drug Administration Schedule , Enzyme-Linked Immunosorbent Assay , Female , Heat-Shock Proteins/genetics , Humans , Immunity, Cellular/immunology , Male , Middle Aged , Vaccines, DNA/genetics
16.
Cancer Gene Ther ; 15(10): 676-84, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18535616

ABSTRACT

Considering that mycobacterial heat-shock protein 65 (hsp65) gene transfer can elicit a profound antitumoral effect, this study aimed to establish the safety, maximum-tolerated dose (MTD) and preliminary efficacy of DNA-hsp65 immunotherapy in patients with advanced head and neck squamous cell carcinoma (HNSCC). For this purpose, 21 patients with unresectable and recurrent HNSCC were studied. Each patient received three ultrasound-guided injections at 21-day intervals of: 150, 600 or 400 microg of DNA-hsp65. Toxicity was graded according to CTCAE directions. Tumor volume was measured before and after treatment using computed tomography scan. The evaluation included tumor mass variation, delayed-type hypersensitivity response and spontaneous peripheral blood mononuclear cell proliferation before and after treatment. The MTD was 400 microg per dose. DNA-hsp65 immunotherapy was well tolerated with moderate pain, edema and infections as the most frequent adverse effects. None of the patients showed clinical or laboratory alterations compatible with autoimmune reactions. Partial response was observed in 4 out of 14 patients who completed treatment, 2 of which are still alive more than 3 years after the completion of the trial. Therefore, DNA-hsp65 immunotherapy is a feasible and safe approach at the dose of 400 microg per injection in patients with HNSCC refractory to standard treatment. Further studies in a larger number of patients are needed to confirm the efficacy of this novel strategy.


Subject(s)
Bacterial Proteins/therapeutic use , Carcinoma, Squamous Cell/therapy , Chaperonins/therapeutic use , Head and Neck Neoplasms/therapy , Immunotherapy/methods , Vaccines, DNA/therapeutic use , Adult , Aged , Bacterial Proteins/immunology , Carcinoma, Squamous Cell/pathology , Chaperonin 60 , Chaperonins/immunology , Feasibility Studies , Female , Head and Neck Neoplasms/pathology , Humans , Immunotherapy/adverse effects , Male , Middle Aged , Vaccines, DNA/immunology
17.
Scand J Immunol ; 66(2-3): 362-71, 2007.
Article in English | MEDLINE | ID: mdl-17635814

ABSTRACT

Human chronic Chagas disease cardiomyopathy (CCC) is an inflammatory-dilated cardiomyopathy occurring years after infection by the protozoan Trypanosoma cruzi. The heart inflammatory infiltrate in CCC shows a 2:1 predominance of CD8(+) in relation to CD4(+) T cells, with a typical Th1-type cytokine profile. However, in vitro expansion of infiltrating T cells from heart biopsy-derived fragments with interleukin-2 (IL-2) and phytohaemagglutinin leads to the outgrowth of CD4(+) over CD8(+) T cells. We hypothesized that survival cytokines, such as IL-2, IL-7 and IL-15 might be differentially involved in the growth and maintenance of heart-infiltrating and peripheral CD8(+) T cells from CCC patients. We found that IL-7 and IL-15 were superior to IL-2 in the expansion and viability of CD8(+) T cells from both PBMC and heart-infiltrating T-cell lines from CCC patients, and the combination of the three cytokines showed synergic effects. Heart-infiltrating CD8(+) T cells showed higher expression of both IL-15R alpha and gamma(c) chain than CD4(+) T cells, which may explain the improvement of CD8(+) T-cell growth in the presence of IL-2 + IL-7 + IL-15. Immunohistochemical identification of IL-15 and the higher mRNA expression of IL-15R alpha, IL-7 and gamma(c) chain in CCC heart tissues compared with control individuals indicate in situ production of survival cytokines and their receptors in CCC hearts. Together, our results suggest that local production of IL-7 and IL-15 may be associated with the maintenance and predominance of CD8(+) T cells, the cells effecting tissue damage in CCC hearts.


Subject(s)
CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/pathology , Chagas Cardiomyopathy/immunology , Chagas Cardiomyopathy/pathology , Interleukin-15/biosynthesis , Interleukin-7/biosynthesis , Myocardium/immunology , Myocardium/pathology , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/metabolism , CD4-Positive T-Lymphocytes/pathology , CD8-Positive T-Lymphocytes/metabolism , Cell Line , Cell Movement/immunology , Cell Proliferation , Cell Survival/immunology , Chagas Cardiomyopathy/metabolism , Chronic Disease , Humans , Immunophenotyping , Interleukin-15/physiology , Interleukin-2/biosynthesis , Interleukin-2/physiology , Interleukin-7/physiology , Leukocytes, Mononuclear/immunology , Leukocytes, Mononuclear/metabolism , Leukocytes, Mononuclear/pathology , Lymphocyte Count , Myocardium/metabolism
18.
Scand J Immunol ; 66(2-3): 352-61, 2007.
Article in English | MEDLINE | ID: mdl-17635813

ABSTRACT

Alloreactive T cells recognize donor antigens by two routes: direct and indirect pathways of allorecognition. Although the direct pathway is reported to be dominant in allograft rejection, indirect allorecognition also plays an important role. Indirect alloreactivity is also observed in renal transplant patients irrespective of rejection. Previously we showed a predominance of interleukin (IL)-10 induced by indirect allorecognition of donor human leucocyte antigen (HLA)-DR peptides, suggesting the existence of indirect alloreactive T cells displaying regulatory activity. In the present work, our objective was to characterize these regulatory T cells. We detected indirect alloproliferation of peripheral blood mononuclear cells (PBMC) from renal transplant patients, induced by donor HLA-DR peptides, dependent on IL-4 or IL-10, suggesting regulatory activity as part of the alloreactive T-cell repertoire. PBMC-derived indirect alloreactive T-cell lines were established and produced both inflammatory and regulatory cytokines. We showed that two of these T-cell lines which were able to inhibit both direct and indirect alloproliferation of another T-cell line from the same patient presented a CD4(+)CD25(+)Foxp3(+) T-cell population. These data support the idea that indirect alloreactive T cells may also have regulatory activity and may contribute to the maintenance of the human renal allograft.


Subject(s)
Antigen Presentation/immunology , Forkhead Transcription Factors/biosynthesis , Kidney Transplantation/immunology , Signal Transduction/immunology , T-Lymphocytes, Regulatory/immunology , T-Lymphocytes, Regulatory/metabolism , Adolescent , Adult , Aged , Cell Proliferation , Child , Humans , Middle Aged , Self Tolerance/immunology
19.
Scand J Immunol ; 66(1): 8-16, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17587341

ABSTRACT

The functioning of the immune system partially relies on T-cell exportation from the thymus, the major site of T-cell differentiation. Although the molecular mechanisms governing this process begin to be elucidated, it is not clear if thyroid hormones can alter the homing of recent thymic emigrants (RTE) to peripheral lymphoid organs. Herein, we investigated whether triiodothyronine (T(3)) could influence the homing of thymus-derived T cells. For that we used intrathymic injection of T(3) in combination with fluorescein isothiocyanate (FITC) to trace, 16 h later, FITC(+) cells, termed RTE, in peripheral lymphoid organs. We observed that T(3) stimulated thymocyte export, increasing the frequency of CD4(+) RTE and CD8(+) RTE in the subcutaneous and mesenteric lymph nodes. By contrast, the relative numbers of CD4(+) RTE in the spleen were decreased. T(3) also changed the differential distribution pattern of CD4(+) RTE, and to a lesser extent CD8(+) RTE in the peripheral lymphoid organs. Moreover, the expression of extracellular matrix (ECM) components, such as laminin and fibronectin, which are known to be involved in T-cell migration, increased in the lymph nodes but not in the spleen following intrathymic T(3) treatment. In conclusion, our data correspond to the first demonstration that in vivo treatment with thyroid hormone stimulates thymic T-cell homing and T-cell distribution in peripheral lymphoid organs.


Subject(s)
Cell Movement/immunology , Lymphoid Tissue/cytology , T-Lymphocyte Subsets/metabolism , T-Lymphocytes/metabolism , Triiodothyronine/metabolism , Animals , Female , Flow Cytometry , Lymphoid Tissue/immunology , Lymphoid Tissue/metabolism , Mice , Mice, Inbred BALB C , T-Lymphocyte Subsets/cytology , T-Lymphocyte Subsets/immunology , T-Lymphocytes/cytology , T-Lymphocytes/immunology
20.
Scand J Immunol ; 66(1): 17-25, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17587342

ABSTRACT

Triiodothyronine (T(3)) exerts several effects on thymus physiology. In this sense, T(3) is known to stimulate thymic microenvironmental cells to enhance the production of extracellular matrix (ECM) moieties, which are relevant in thymocyte migration. Here, we further investigated the in vivo influence of T(3) on ECM production, as well as on ECM-related T-cell migration events. For this, BALB/c mice were subjected to two protocols of T(3) treatment: long-term (30 days) i.p. daily T(3) injections or short-term (16 h) after a single T(3) intrathymic injection. These two treatments did promote an enhancement in the expression of fibronectin and laminin, in both cortex and medullary regions of the thymic lobules. As revealed by the long-term treatment, the expression of ECM protein receptors, including VLA-4, VLA-5 and VLA-6, was also increased in thymocyte subsets issued from T(3)-treated mice. We further used thymic nurse cells (TNC) as an in vitro system to study the ECM-related migration of immature thymocytes in the context of thymic epithelial cells. Even a single intrathymic injection of T(3) resulted in an increase in the ex vivo exit of thymocytes from TNC lymphoepithelial complexes. Accordingly, when we evaluated thymocyte migration in transwell chambers pre-coated with ECM proteins, we found an increase in the numbers of migrating cells, when thymocytes were derived from T(3)-treated mice. Overall, our data show that in vivo intrathymic short-term i.p. long-term T(3) treatments are able to modulate thymocyte migration, probably via ECM-mediated interactions.


Subject(s)
Cell Movement/immunology , Extracellular Matrix Proteins/biosynthesis , Lymphoid Tissue/cytology , T-Lymphocytes/metabolism , Triiodothyronine/metabolism , Animals , Extracellular Matrix/metabolism , Female , Immunohistochemistry , Lymphoid Tissue/immunology , Mice , Mice, Inbred BALB C , T-Lymphocytes/cytology , T-Lymphocytes/immunology
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