Biodemes and zymodemes of Trypanosoma cruzi strains: correlations with clinical data and experimental pathology

With the objective of establishing biological and biochemical characteristics of a significant number of Trypanosoma cruzi strains from different geographical areas, 138 strains isolated from naturally infected humans, triatomine or vertebrate hosts were studied; 120 were isolated from different areas of Brazil and 18 from other South and Central American countries. Inocula from triatomine or culture forms were injected into suckling Swiss mice, followed by passages into mice 10 to 12 g. Biological characters and histopathological study permitted the inclusion of the strains into three Types or biodemes: I, II, III. Isoenzymic analysis confirmed a correspondence between the biodemes and zymodemes : Type I and Z2b, Type II and Z2, Type III and Z1. Results showed the ubiquitary distribution of the several types of strains. The predominance of the same Type and zymodeme in one geographical area was confirmed : Type II strains among the human cases from eastern Bahia and east of Goiás; Type III strains from humans of north Brazil and Central America and from silvatic vectors or vertebrates from other geographical areas. The biological types of strains correlate with different histopathological lesions considering cardiac involvement and neuronal lesions. These findings suggest that the biological behavior together with isoenzymes patterns and pathological pictures in the vertebrate host can be an important tool for establishing correlations between strains behavior and clinico-pathological manifestations of Chagas' disease in different geographical areas.

Detection of HTLV-IIa in blood donors in an urban area of the Amazon Region of Brazil (Belém, PA)

The human lymphotropic viruses type I (HTLV-I) and type II (HTLV-II) are members of a group of mammalian retroviruses with similar biological properties, and blood transfusion is an important route of transmission. HTLV-I is endemic in a number of different geographical areas and is associated with several clinical disorders. HTLV-II is endemic in several Indian groups of the Americas and intravenous drug abusers in North and South America, Europe and Southeast Asia. During the year of 1995, all blood donors tested positive to HTLV-I/II in the State Blood Bank (HEMOPA), were directed to a physician and to the Virus Laboratory at the Universidade Federal do Pará for counselling and laboratory diagnosis confirmation. Thirty-five sera were tested by an enzyme immune assay, and a Western blot that discriminates HTLV-I and HTLV-II infection. Two HTLV-II positive samples were submitted to PCR analysis of pX and env genomic region, and confirmed to be of subtype IIa. This is the first detection in Belém of the presence of HTLV-IIa infection among blood donors. This result emphasizes that HTLV-II is also present in urban areas of the Amazon region of Brazil and highlights the need to include screening tests that are capable to detect antibodies for both types of HTLV.

Uncovering the role of IFNAR1 in Experimental Cerebral malaria

Dissertation presented the Ph.D degree in Biology

Reinfections with strains of Trypanosoma cruzi, of different biodemes as a factor of aggravation of myocarditis and myositis in mice

Reinfections with Trypanosoma cruzi in patients from endemic areas have been claimed to be an aggravation factor of cardiac manifestations in Chagas' disease. In the present study, the influence of triple infections with strains of different biodemes, on cardiac and skeletal muscle lesions was experimentally tested. Fifty eight mice chronically infected with the Colombian strain (Biodeme Type III) were successively reinfected as follows: 1st group - reinfected with 21 SF strain (Type II) followed by Y strain (Type I ); 2nd - group reinfections with Y strain followed by 21SF strain. Isoenzyme analysis of parasites from hemocultures obtained from triple infected mice, revealed the patterns of three distinct zymodemes in the same animal. Each Trypanosoma cruzi strain was reisolated after four passages in mice on either the 7th, 14th or 30th day after inoculation with the blood of triple infected mice. Histopathology results demonstrated a significant exacerbation of cardiac and skeletal muscle inflammatory lesions, confirmed by morphometric evaluation, in mice with triple infection. No aggravation of parasitism was detected. The possibility of an enhancement of cellular response in the triple infected mice is suggested.

Adult T-cell leukemia/lymphoma: report of two cases

Adult T-cell leukemia/lymphoma is a lymphoproliferative disorder of mature T lymphocytes associated with infection with human T-cell lymphotrophic virus type I (HTLV-I). Adult T-cell leukemia/lymphoma is characterized by clinical and laboratory polymorphism that allows it to be classified into four distinct subgroups: smoldering, chronic, acute and lymphomatous types. We present here two cases of adult T-cell leukemia/lymphoma, respectively in the acute and lymphomatous forms of the disease. Case 1 was a 35-year-old woman who presented abdominal distension accompanied by hepatosplenomegaly, adenomegaly, skin lesions, positivity for anti-HTLV-I antibodies and leukocytosis with the presence of flower cells. Case 2 was a 38-year-old man who was admitted with generalized lymphadenomegaly, positivity for anti-HTLV-I antibodies, hypercalcemia and osteolytic lesions. In this paper, we correlate the clinical-laboratory findings of these two cases with data in the literature.

Glomerulonephritis in schistosomiasis mansoni: a time to reappraise

INTRODUCTION: The current prevalence of glomerulonephritis in patients with hepatosplenic schistosomiasis mansoni in Brazil was evaluated. METHODS: Sixty three patients (mean age 45.5±11 years) attending the outpatient infectious disease clinic of a University Hospital in Belo Horizonte, Brazil, from 2007 to 2009, were consecutively examined and enrolled in the present investigation. Diagnosis of hepatosplenic schistosomiasis was based on epidemiological, clinical and parasitological data and imaging techniques. Eight patients, who presented >30mg/day albuminuria, were submitted to percutaneous ultrasound guided renal biopsy. Kidney tissue fragments were examined under light, direct immunofluorescence and electron microscopy. RESULTS: All patients showed mesangial enlargement. In five, mesangial hypercellularity was observed and four presented duplication of the glomerular basement membrane. Areas of glomerular sclerosis were diagnosed in four. Deposits of immunoglobulin M and C3 were present in six samples; deposits of IgG in four, IgA in three and C1q in two samples. In all patients, immunoglobulin A was reported in the lumen of renal tubules. Deposits of kappa and lambda were observed in six samples. Electron microscopy revealed dense deposits in the glomerular tissue of three patients. Arterial hypertension, small esophageal varices, slight increases in serum creatinine and decreases in serum albumin were associated with glomerular disease. CONCLUSIONS: Renal disease associated with hepatosplenic schistosomiasis was verified in 12.7% of patients and type I membranoproliferative glomerulonephritis was observed in 50% of them. Schistosomal glomerulopathy still is an important problem in patients with hepatosplenic schistosomiasis in Brazil.

Cryopreservation of Cell Sheets of Adipose Stem Cells: Limitations and Successes

Cell Sheets of hASCs (hASCs-CS) have been previously proposed for wound healing applications(1, 2) and despite the concern for production time reduction, the possibility of having these hASCs-CS off-the-shelf is appealing. The goal of this work was to define a cryopreservation methodology allowing to preserve cells viability and the properties CS matrix. hASCs-CS obtained from three different donors were created in UP-cell thermoresponsive dishes(Nunc, Germany) as previously reported(1,2). Different cryopreservation conditions were considered: i)FBS plus DMSO(5% and10%); ii)0.4M of Trehalose plus DMSO (5% and 10%); iii)cryosolution PLL (Akron Biotech, USA); and iv)vitrification. The cryopreservation effect was first assessed for cellular viability by flow cytometry using 7-AAD, and after dissociating the hASCs-CS with collagenase and trypsin-EDTA 0.25%. The expression (RT-PCR) and deposition (western blot and immunocytochemistry) of collagen type I, laminin and fibronectin, and the organization (TEM) of the extracellular matrix was further assessed before and after hASCs-CS cryopreservation to determine a potential effect of the method over matrix composition and integrity. The obtained results confirmed that cell viability is affected by the cryopreservation methodology, as shown before for different CS(3). Interestingly, the matrix properties were not significantly altered and the typical cell sheetâ s easiness of manipulation for transplantation was not lost.

In vitro chondrogenic commitment of human Wharton's jelly stem cells by co-culture with human articular chondrocytes.

Wharton's jelly stem cells (WJSCs) are a potential source of transplantable stem cells in cartilage-regenerative strategies, due to their highly proliferative and multilineage differentiation capacity. We hypothesized that a non-direct co-culture system with human articular chondrocytes (hACs) could enhance the potential chondrogenic phenotype of hWJSCs during the expansion phase compared to those expanded in monoculture conditions. Primary hWJSCs were cultured in the bottom of a multiwell plate separated by a porous transwell membrane insert seeded with hACs. No statistically significant differences in hWJSCs duplication number were observed under either of the culture conditions during the expansion phase. hWJSCs under co-culture conditions show upregulations of collagen type I and II, COMP, TGFβ1 and aggrecan, as well as of the main cartilage transcription factor, SOX9, when compared to those cultured in the absence of chondrocytes. Chondrogenic differentiation of hWJSCs, previously expanded in co-culture and monoculture conditions, was evaluated for each cellular passage using the micromass culture model. Cells expanded in co-culture showed higher accumulation of glycosaminoglycans (GAGs) compared to cells in monoculture, and immunohistochemistry for localization of collagen type I revealed a strong detection signal when hWJSCs were expanded under monoculture conditions. In contrast, type II collagen was detected when cells were expanded under co-culture conditions, where numerous round-shaped cell clusters were observed. Using a micromass differentiation model, hWJSCs, previously exposed to soluble factors secreted by hACs, were able to express higher levels of chondrogenic genes with deposition of cartilage extracellular matrix components, suggesting their use as an alternative cell source for treating degenerated cartilage.

On the occurrence of cyanolipids In Paullinia carpopodea cambess And P. cupana Kunth seed oils

Paullinia carpopodea seed oil contains 70% type Icyanolipids with cyanogenetic properties, as proven by chemical and spectrometric techniques. P. cupana seed oil also contains cyanogenic type I cyanolipids, according to its 1Ή-NMR spectrum. The existing controversy in the literature about the presence and/or type of cyanolipids in P. cupana seed oil is probably due to the low amount of these compounds (0.2%) in the seeds.

Aging and Alzheimer's disease: Searching for novel molecular cues

Tese de Doutoramento em Ciências da Saúde

Mechanical fatigue performance of PCL-chondroprogenitor constructs after cell culture under bioreactor mechanical stimulus

In tissue engineering of cartilage, polymeric scaffolds are implanted in the damaged tissue and subjected to repeated compression loading cycles. The possibility of failure due to mechanical fatigue has not been properly addressed in these scaffolds. Nevertheless, the macroporous scaffold is susceptible to failure after repeated loading-unloading cycles. This is related to inherent discontinuities in the material due to the micropore structure of the macro-pore walls that act as stress concentration points. In this work, chondrogenic precursor cells have been seeded in Poly-ε-caprolactone (PCL) scaffolds with fibrin and some were submitted to free swelling culture and others to cyclic loading in a bioreactor. After cell culture, all the samples were analyzed for fatigue behavior under repeated loading-unloading cycles. Moreover, some components of the extracellular matrix (ECM) were identified. No differences were observed between samples undergoing free swelling or bioreactor loading conditions, neither respect to matrix components nor to mechanical performance to fatigue. The ECM did not achieve the desired preponderance of collagen type II over collagen type I which is considered the main characteristic of hyaline cartilage ECM. However, prediction in PCL with ECM constructs was possible up to 600 cycles, an enhanced performance when compared to previous works. PCL after cell culture presents an improved fatigue resistance, despite the fact that the measured elastic modulus at the first cycle was similar to PCL with poly(vinyl alcohol) samples. This finding suggests that fatigue analysis in tissue engineering constructs can provide additional information missed with traditional mechanical measurements.

Search for heavy Majorana neutrinos with the ATLAS detector in pp collisions at s√=8 TeV

A search for heavy Majorana neutrinos in events containing a pair of high-pT leptons of the same charge and high-pT jets is presented. The search uses 20.3fb−1 of pp collision data collected with the ATLAS detector at the CERN Large Hadron Collider with a centre-of-mass energy of s√=8 TeV. The data are found to be consistent with the background-only hypothesis based on the Standard Model expectation. In the context of a Type-I seesaw mechanism, limits are set on the production cross-section times branching ratio for production of heavy Majorana neutrinos in the mass range between 100 and 500 GeV. The limits are subsequently interpreted as limits on the mixing between the heavy Majorana neutrinos and the Standard Model neutrinos. In the context of a left-right symmetric model, limits on the production cross-section times branching ratio are set with respect to the masses of heavy Majorana neutrinos and heavy gauge bosons WR and Z′.

A five year follow-up study of 11 patients with bipolar disorder

OBJECTIVE: To study the long-term follow-up of patients with bipolar disorder (BPD). METHOD: Eleven outpatients with BPD type I were followed up naturalistically for five years at a university teaching hospital. The Clinical Global Impression Scale (BPD version) was used to evaluate the occurrence of affective episodes, and the Strauss-Carpenter Outcome Scale was used to evaluate social and occupational functioning. RESULTS: The majority of patients were symptomatic most of the time, with predominantly depressive episodes. Overall, patients remained euthymic a mean of 47.7% of the time. Despite a low rate of hospitalization, social and occupational functioning was poor in the majority of patients. A poor disease course with respect to work-related functioning was associated with fewer months of euthymia with a longer duration of depressive episodes. The total number of months of euthymia negatively correlated with the patient's age and disease duration. CONCLUSION: Despite the small sample size, the present findings appear to corroborate previous studies on the evolution of BPD. Most of the patients had a poor disease course, with long symptomatic periods, particularly depressive episodes, and significantly impaired social and occupational functioning.

Marine Collagen/Apatite scaffolds envisaging tissue engineering applications

Despite the vast investigation and the large amount of products already available in the market to treat the different bone defects there is still a growing need to develop more advanced and complex therapeutic strategies. In this context, a mixture of Marine Hydroxyapatite-Fluorapatite:Collagen (HA-FP:ASC) seems to be a promising solution to overcome these bone defects, specifically, dental defects. HA-FP particles (20–63 μm) were obtained through pyrolysis (950°C, 12 h) of shark teeth (Isurus oxyrinchus, P. glauca), and Type I collagen was isolated from Prionace glauca skin as previously described (1). After the steps of purification, collagen was solubilized in 0.5 M acetic acid and HA-FP added producing three different formulations: were produced, 30:70, 50:50 and 70:30 of HA-FP:ASC, respectively. EDC/NHS and HMDI binding agents were used to stabilize the produced scaffolds. Mechanical properties were evaluated by compression tests. SEM analysis allowed observing the mineral deposition, after immersion in simulated body fluid and also permitted to evaluate how homogenous was the distribution of HA-FP in the different scaffold formulations, also confirmed by μ-CT assay. It was readily visible by Cytotoxicity and life/dead CLSM assays that cells were able to adhere and proliferate in the produced scaffolds. Scaffolds crosslinked with EDC/NHS showed lower cytotoxicity, being the ones chosen for further cellular evaluation.

Epworth's sleepiness scale in outpatients with different values of arterial blood pressure

OBJECTIVE: To compare sleepiness scores of the Epworth scale in patients with different levels of arterial pressure when undergoing outpatient monitoring within the context of clinical evaluation. METHODS: A total of 157 patients selected for outpatient monitoring of arterial pressure during hypertension evaluation were divided into 3 groups: group 1 - normotensive; group 2 - hypertensive; group 3 - resistant hypertensive. For analysis, values > or = 11 were considered as associated with respiratory disturbances during sleep. RESULTS: Seventeen (10.8%) patients in group 1, 112 (71.3%) in group 2, and 28 (17.8%) in group 3, which was composed of aged, more severely hypertensive individuals, were analyzed. Groups were similar relative to sex and body mass index, but different in relation to systolic and diastolic pressure levels and age. Despite an absolute difference, no statistically significant difference occurred between Epworth scores and in the proportion of patients with values > or = 11 (5.9% vs. 18.8% vs. 212.4%; P=0.37). Despite the positive association between degree of sleepiness measured with the scale and the severity of the hypertension, no statistical significance occurred following control by age (p=0.18). CONCLUSION: A positive correlation exists between degree of sleepiness and hypertension severity. The absence of a statistical significance shown in the present study could be due to a beta type of error. Instruments that render this complaint into an objective finding could help in the pursuit of an investigation of respiratory disturbances during sleep in more severely hypertensive patients, and should therefore be studied better.