Arthritis is linked to local and systemic activation of coagulation and fibrinolysis pathways.

BACKGROUND: Activation of coagulation and fibrinolysis play a role in the pathophysiology of experimental arthritis. Objective: To determine the extent of activation of the coagulation and fibrinolytic pathways in different joint diseases in humans and to ascertain the factors that may influence fibrin deposition within the joint. METHODS: Plasma from normal subjects (controls, n= 21) and plasma and synovial fluid samples from patients with rheumatoid arthritis (RA; n = 64), osteoarthritis (OA; n = 29), spondyloarthropathy (SpA; n = 22) and crystal arthritis (CA; n = 25) were analyzed for the levels of TF (tissue factor) and tissue factor pathway inhibitor (TFPI) activities, thrombin-antithrombin III (TAT) complexes, and F1 + 2 (thrombin fragment), fibrin d-dimer and thrombin-activated fibrinolysis inhibitor (TAFI) antigenic levels. The measurements were analyzed by pairwise correlation with each other as well as with standard parameters of inflammation [C-reactive protein (CRP), joint leukocyte count]. Inter-group comparisons were performed to look for disease-specific differences. RESULTS: Compared with healthy controls, patients with joint diseases had higher levels of TAT, F1 + 2 and d-dimers in their plasma. In the synovial fluid, TF activity, TAT, d-dimers, and TAFI were significantly higher in inflammatory arthritides than in OA. The levels were highest in RA patients. In the plasma, TF activity was correlated with TAT and d-dimer levels with CRP, TFPI, and TAT. In the synovial fluid, TF activity correlated with plasma CRP levels, synovial fluid leukocyte count, and synovial TAT and TAFI levels. In addition, synovial d-dimers correlated with CRP, and synovial TAFI levels were correlated with synovial F1 + 2 and TAT. CONCLUSIONS: Activation of the coagulation and fibrinolytic cascades in the joint and in the circulation is evident in both inflammatory and degenerative joint diseases. Within the joint, inflammatory mechanisms leading to TF-mediated activation of the coagulation pathway and subsequent fibrin deposition is the most likely explanation for the observed findings. In the plasma, the link between inflammation (CRP increase) and TF activation is weak, and a non-TF-mediated mechanism of coagulation activation could explain these findings. RA is characterized by significantly higher levels of TAT in the synovial fluid and plasma than other arthritides. Although fibrinolytic activity is linked to inflammation, the increased amounts of TAFI in the joint, particularly in RA, may explain why fibrin formation is so prominent in this condition compared with other joint diseases.

Lack of Correlation between Seminal and Plasma HIV-1 Viral Loads is Associated with CD4T Cell Depletion in Therapy-naïve HIV-1+ Patients

The present study was conducted to investigate a possible correlation between plasma (PVL) and seminal viral load (SVL) on treatment-naïve HIV-1-infected patients in Vitória, ES, Brazil. We also evaluated whether the progressive immunosuppression associated with HIV disease (as evidenced by declining CD4 T cell counts) has any impact on the correlation between PVL and SVL HIV-1. Viral load on paired blood and semen samples from 56 consecutive treatment-naïve patients were evaluated and compared to CD4 cell counts. Viral load and T cell counts (cells/µl) were determined by NASBA and by flow cytometry, respectively. Overall, a strong positive correlation between PVL and SVL (rho = 0.438, p = 0.001) was observed. However, when patients were grouped according to their CD4 counts, this correlation was only significant among patients with CD4 counts > 200 cells/µl. Results presented here demonstrate the existence of a strong correlation between PVL and SVL on patients with CD4 cell counts > 200 cells/µl, suggesting that this association may correlate with disease progression.

Schistosomiasis mansoni in low transmission areas: abdominal ultrasound

In endemic areas with low prevalence and low intensity of infection, the diagnosis of hepatic pathology due to the Schistosoma mansoni infection is very difficult. In order to establish the hepatic morbidity, a double-blind study was achieved in Venezuelan endemic areas, with one group of patients with schistosomiasis and the other one of non-infected people, that were evaluated clinically and by abdominal ultrasound using the Cairo classification. Schistosomiasis diagnosis was established based on parasitologic and serological tests. The increase of the hepatic size at midclavicular and midsternal lines (in hepatometry) and the hard liver consistency were the clinical parameters able to differentiate infected persons from non infected ones, as well as the presence of left lobe hepatomegaly detected by abdominal ultrasound. The periportal thickening, especially the mild form, was frequent in all age groups in both infected and uninfected patients. There was not correlation between the intensity of infection and ultrasound under the current circumstances. Our data suggest that in Venezuela, a low endemic area of transmission of schistosomiasis, the hepatic morbidity is mild and uncommon. The Cairo classification seems to overestimate the prevalence of periportal pathology. The specificity of the method must be improved, especially for the recognition of precocious pathology. Other causes of hepatopathies must be investigated.

Correlation of male genital filaments and female spermathecal ducts in New World sand flies of the Lutzomyia intermedia species complex (Diptera: Psychodidae, Phlebotominae)

The lengths of the male genital filaments and female spermathecal ducts were measured in phlebotomine sand flies of the Lutzomyia intermedia species complex and the ratios between these characters calculated. Ratios for L. intermedia s. s. from Northeast vs Southeast Brazil (Espírito Santo and Minas Gerais), Espírito Santo/Minas Gerais vs Rio de Janeiro/São Paulo and L. intermedia vs L. neivai were significantly different at P < 0.1, 0.05 and 0.01 respectively when compared using ANOVA. The spermathecal ducts and genital filaments of L. intermedia were significantly longer than those of L. neivai (P < 0.01) and could be used to differentiate these species. The taxonomic and biological significance of these differences is discussed.

Parameters affecting cellular invasion and escape from the parasitophorous vacuole by different infective forms of Trypanosoma cruzi

In this study we have examined certain aspects of the process of cell invasion and parasitophorous vacuole escape by metacyclic trypomastigotes and extracellular amastigote forms of Trypanosoma cruzi (G strain). Using Vero (and HeLa) cells as targets, we detected differences in the kinetics of vacuole escape by the two forms. Alcalinization of intercellular pH influenced both invasion as well as the escape from the parasitophorous vacuole by metacyclic trypomastigotes, but not the escape kinetics of extracellular amastigotes. We used sialic acid mutants as target cells and observed that the deficiency of this molecule facilitated the escape of both infective forms. Hemolysin activity was only detected in extracellular amastigotes and neither form presented detectable transialidase activity. Invasion of extracellular amastigotes and trypomastigotes in Vero cells was affected in different ways by drugs that interfere with host cell Ca2+ mobilization. These results are in line with previous results that indicate that metacyclic trypomastigotes and extracellular amastigote forms utilize mechanisms with particular features to invade host cells and to escape from their parasitophorous vacuoles.

Life tables and reproductive parameters of Lutzomyia spinicrassa (Diptera: Psychodidae) under laboratory conditions

Lutzomyia spinicrassa is a vector of Leishmania braziliensis in Colombia. This sand fly has a broad geographical distribution in Colombia and Venezuela and it is found mainly in coffee plantations. Baseline biological growth data of L. spinicrassa were obtained under experimental laboratory conditions. The development time from egg to adult ranged from 59 to 121 days, with 12.74 weeks in average. Based on cohorts of 100 females, horizontal life table was constructed. The following predictive parameters were obtained: net rate of reproduction (8.4 females per cohort female), generation time (12.74 weeks), intrinsic rate of population increase (0.17), and finite rate of population increment (1.18). The reproductive value for each class age of the cohort females was calculated. Vertical life tables were elaborated and mortality was described for the generation obtained of the field cohort. In addition, for two successive generations, additive variance and heritability for fecundity were estimated.

Therapeutic drug monitoring of imatinib: Bayesian and alternative methods to predict trough levels

Background: The imatinib trough plasma concentration (C(min)) correlates with clinical response in cancer patients. Therapeutic drug monitoring (TDM) of plasma C(min) is therefore suggested. In practice, however, blood sampling for TDM is often not performed at trough. The corresponding measurement is thus only remotely informative about C(min) exposure. Objectives: The objectives of this study were to improve the interpretation of randomly measured concentrations by using a Bayesian approach for the prediction of C(min), incorporating correlation between pharmacokinetic parameters, and to compare the predictive performance of this method with alternative approaches, by comparing predictions with actual measured trough levels, and with predictions obtained by a reference method, respectively. Methods: A Bayesian maximum a posteriori (MAP) estimation method accounting for correlation (MAP-ρ) between pharmacokinetic parameters was developed on the basis of a population pharmacokinetic model, which was validated on external data. Thirty-one paired random and trough levels, observed in gastrointestinal stromal tumour patients, were then used for the evaluation of the Bayesian MAP-ρ method: individual C(min) predictions, derived from single random observations, were compared with actual measured trough levels for assessment of predictive performance (accuracy and precision). The method was also compared with alternative approaches: classical Bayesian MAP estimation assuming uncorrelated pharmacokinetic parameters, linear extrapolation along the typical elimination constant of imatinib, and non-linear mixed-effects modelling (NONMEM) first-order conditional estimation (FOCE) with interaction. Predictions of all methods were finally compared with 'best-possible' predictions obtained by a reference method (NONMEM FOCE, using both random and trough observations for individual C(min) prediction). Results: The developed Bayesian MAP-ρ method accounting for correlation between pharmacokinetic parameters allowed non-biased prediction of imatinib C(min) with a precision of ±30.7%. This predictive performance was similar for the alternative methods that were applied. The range of relative prediction errors was, however, smallest for the Bayesian MAP-ρ method and largest for the linear extrapolation method. When compared with the reference method, predictive performance was comparable for all methods. The time interval between random and trough sampling did not influence the precision of Bayesian MAP-ρ predictions. Conclusion: Clinical interpretation of randomly measured imatinib plasma concentrations can be assisted by Bayesian TDM. Classical Bayesian MAP estimation can be applied even without consideration of the correlation between pharmacokinetic parameters. Individual C(min) predictions are expected to vary less through Bayesian TDM than linear extrapolation. Bayesian TDM could be developed in the future for other targeted anticancer drugs and for the prediction of other pharmacokinetic parameters that have been correlated with clinical outcomes.

Brain aging in the oldest-old.

Nonagenarians and centenarians represent a quickly growing age group worldwide. In parallel, the prevalence of dementia increases substantially, but how to define dementia in this oldest-old age segment remains unclear. Although the idea that the risk of Alzheimer's disease (AD) decreases after age 90 has now been questioned, the oldest-old still represent a population relatively resistant to degenerative brain processes. Brain aging is characterised by the formation of neurofibrillary tangles (NFTs) and senile plaques (SPs) as well as neuronal and synaptic loss in both cognitively intact individuals and patients with AD. In nondemented cases NFTs are usually restricted to the hippocampal formation, whereas the progressive involvement of the association areas in the temporal neocortex parallels the development of overt clinical signs of dementia. In contrast, there is little correlation between the quantitative distribution of SP and AD severity. The pattern of lesion distribution and neuronal loss changes in extreme aging relative to the younger-old. In contrast to younger cases where dementia is mainly related to severe NFT formation within adjacent components of the medial and inferior aspects of the temporal cortex, oldest-old individuals display a preferential involvement of the anterior part of the CA1 field of the hippocampus whereas the inferior temporal and frontal association areas are relatively spared. This pattern suggests that both the extent of NFT development in the hippocampus as well as a displacement of subregional NFT distribution within the Cornu ammonis (CA) fields may be key determinants of dementia in the very old. Cortical association areas are relatively preserved. The progression of NFT formation across increasing cognitive impairment was significantly slower in nonagenarians and centenarians compared to younger cases in the CA1 field and entorhinal cortex. The total amount of amyloid and the neuronal loss in these regions were also significantly lower than those reported in younger AD cases. Overall, there is evidence that pathological substrates of cognitive deterioration in the oldest-old are different from those observed in the younger-old. Microvascular parameters such as mean capillary diameters may be key factors to consider for the prediction of cognitive decline in the oldest-old. Neuropathological particularities of the oldest-old may be related to "longevity-enabling" genes although little or nothing is known in this promising field of future research.

Indoor air microbiological evaluation of offices, hospitals, industries, and shopping centers

In this study it was compared the MAS-100 and the Andersen air samplers' performances and a similar trend in both instruments was observed. It was also evaluated the microbial contamination levels in 3060 samples of offices, hospitals, industries, and shopping centers, in the period of 1998 to 2002, in Rio de Janeiro city. Considering each environment, 94.3 to 99.4% of the samples were the allowed limit in Brazil (750 CFU/m³). The industries' results showed more important similarity among fungi and total heterotrophs distributions, with the majority of the results between zero and 100 CFU/m³. The offices' results showed dispersion around 300 CFU/m³. The hospitals' results presented the same trend, with an average of 200 CFU/m³. Shopping centers' environments showed an average of 300 CFU/m³ for fungi, but presented a larger dispersion pattern for the total heterotrophs, with the highest average (1000 CFU/m³). It was also investigated the correlation of the sampling period with the number of airborne microorganisms and with the environmental parameters (temperature and air humidity) through the principal components analysis. All indoor air samples distributions were very similar. The temperature and air humidity had no significant influence on the samples dispersion patterns.

Antibiotic-dependent correlation between drug-induced killing and loss of luminescence in Streptococcus gordonii expressing luciferase.

Measuring antibiotic-induced killing relies on time-consuming biological tests. The firefly luciferase gene (luc) was successfully used as a reporter gene to assess antibiotic efficacy rapidly in slow-growing Mycobacterium tuberculosis. We tested whether luc expression could also provide a rapid evaluation of bactericidal drugs in Streptococcus gordonii. The suicide vectors pFW5luc and a modified version of pJDC9 carrying a promoterless luc gene were used to construct transcriptional-fusion mutants. One mutant susceptible to penicillin-induced killing (LMI2) and three penicillin-tolerant derivatives (LMI103, LMI104, and LMI105) producing luciferase under independent streptococcal promoters were tested. The correlation between antibiotic-induced killing and luminescence was determined with mechanistically unrelated drugs. Chloramphenicol (20 times the MIC) inhibited bacterial growth. In parallel, luciferase stopped increasing and remained stable, as determined by luminescence and Western blots. Ciprofloxacin (200 times the MIC) rapidly killed 1.5 log10 CFU/ml in 2-4 hr. Luminescence decreased simultaneously by 10-fold. In contrast, penicillin (200 times the MIC) gave discordant results. Although killing was slow (&lt; or = 0.5 log10 CFU/ml in 2 hr), luminescence dropped abruptly by 50-100-times in the same time. Inactivating penicillin with penicillinase restored luminescence, irrespective of viable counts. This was not due to altered luciferase expression or stability, suggesting some kind of post-translational modification. Luciferase shares homology with aminoacyl-tRNA synthetase and acyl-CoA ligase, which might be regulated by macromolecule synthesis and hence affected in penicillin-inhibited cells. Because of resemblance, luciferase might be down-regulated simultaneously. Luminescence cannot be universally used to predict antibiotic-induced killing. Thus, introducing reporter enzymes sharing mechanistic similarities with normal metabolic reactions might reveal other effects than those expected.

Single and concomitant experimental infectionsby Endotrypanum spp. and Leishmania (Viannia) guyanensis (Kinetoplastida: Trypanosomatidae) in the Neotropical sand fly Lutzomyia longipalpis (Diptera: Psychodidae)

Lutzomyia longipalpis females received single and mixed infections with Endotrypanum and Leishmania. Two biological parameters were analyzed: the percentage of infected females and the distribution of flagellates in the gut of the females. The principal comparisons were performed between (1) two strains of Endotrypanum, (2) cloned versus primary sample of one strain of Endotrypanum, (3) Endotrypanum versus Leishmania guyanensis, and (4) the pattern of flagellates behaviour by optical microscopy in females with single or mixed infection versus the identification of parasites isolated from digestive tracts by isoenzyme electrophoresis. Flagellates of Endotrypanum showed distinct patterns of infection suggesting that there is variation between and within strains. The distribution of Endotrypanum and L. guyanensis differed significantly in relation to the colonization of the stomodeal valve. In co-infection with L. guyanensis, a large number of flagellates were seen to be plentifully infecting the stomodeal valve in significantly more specimens than in females infected by Endotrypanum only. However, the electrophoretic profiles of isoenzymes of parasites recovered from all co-infected specimens corresponded to Endotrypanum. This suggests that the mere correlation sand fly infection-biochemical analysis of isolates may induce parasitological incorrect consideration.

CD30 in PTCLS: correlation between RNA and protein levels in a large european series from the LYSA

Introduction: CD22 is expressed on most B-non-Hodgkin lymphomas (NHL); inotuzumab ozogamicin (INO) is an anti-CD22 antibody conjugated to calicheamicin. This study evaluated the safety and tolerability of INO plus R-CVP in patients (pts) with relapsed/refractory CD22+ B-NHL. Efficacy data were also collected. Methods: Part 1 of this open-label study identified a maximum tolerated dose (MTD) of INO 0.8mg/m,2 on day 2 plus R-CVP (rituximab 375mg/m,2 cyclophosphamide 750mg/m,2 and vincristine 1.4mg/m,2 on day 1; prednisone 40mg/m,2 on days 1-5) every 21 days. Subsequently, pts were enrolled in the MTD confirmation cohort (part 2, n = 10), which required a dose-limiting toxicity rate of <33% in cycle 1 and <4 pts discontinuing prior to cycle 3 due to an adverse event (AE) in the MTD expansion cohort (part 3, n = 22), which explored preliminary activity. Results: Parts 2 and 3 enrolled 32 pts: 16 pts with diffuse large B-cell lymphoma, 15 with follicular lymphoma and one with mantle cell lymphoma. Median age was 64.5 years (range 44-81 years); 34% of pts had 1 prior regimen, 34% had 2, 28% had ≥3 and 3% had none (median 2; range 0-6).Median treatment duration was five cycles (range 1-6). Part 2 confirmed the MTD as standard dose R-CVP plus INO 0.8mg/m,2; 2/10 pts had a dose-limiting toxicity (grade 3 increased ALT/AST, grade 4 neutropenia requiring G-CSF). One pt discontinued because of an AE prior to cycle 3. Common treatment-related AEs were thrombocytopenia (78%), neutropenia (66%), fatigue (50%), leukopenia (50%), nausea (41%) and lymphopenia (38%); common grade 3/4 AEs were neutropenia (63%), thrombocytopenia (53%), leukopenia (38%) and lymphopenia (31%). There was one case of treatment-related fatal pneumonia with grade 4 neutropenia. Ten pts discontinued treatment due to AEs; thrombocytopenia/delayed platelet recovery was the leading cause (grade 1/2, n = 6; grade 3/4, n = 3). Objective response rate (ORR) was 77% (n = 24/31 evaluable pts), including 26% (n=8/31) with complete response (CR); three pts had stable disease. Of the pts with follicular lymphoma, ORR was 100% (n = 15/15), including seven pts with CR. Of the pts with diffuse large B-cell lymphoma, ORR was 60% (n = 9/16), including one pt with CR. Conclusions: Results suggest that INOplus R-CVP has acceptable toxicity and promising activity in relapsed/refractory CD22+ B-NHL. The most common grade 3/4 AEs were hematologic. Follow-up for progression-free and overall survival is ongoing.

Measuring an effect size from dichotomized data : contrasted results whether using a correlation or an odds-ratio

It is well known that dichotomizing continuous data has the effect to decrease statistical power when the goal is to test for a statistical association between two variables. Modern researchers however are focusing not only on statistical significance but also on an estimation of the "effect size" (i.e., the strength of association between the variables) to judge whether a significant association is also clinically relevant. In this article, we are interested in the consequences of dichotomizing continuous data on the value of an effect size in some classical settings. It turns out that the conclusions will not be the same whether using a correlation or an odds ratio to summarize the strength of association between the variables: Whereas the value of a correlation is typically decreased by a factor pi/2 after each dichotomization, the value of an odds ratio is at the same time raised to the power 2. From a descriptive statistical point of view, it is thus not clear whether dichotomizing continuous data leads to a decrease or to an increase in the effect size, as illustrated using a data set to investigate the relationship between motor and intellectual functions in children and adolescents

Nutritional status using the Mini Nutritional Assessment questionnaire and its relationship with bone quality in a population of institutionalized elderly women.

Malnutrition, a risk factor for osteoporotic fractures, is frequent in elderly people and, is underdiagnosed and undertreated. There are only few studies on the nutritional status of elderly people in Europe. The Mini Nutritional Assessment (MNA) is a non invasive and validated questionnaire to evaluate nutritional status in elderly people, classified in three groups: 1 degree score < 17: malnourished, 2 degrees score >17 and < 24: at risk of malnutrition, 3 degrees score >24: well-nourished, with a maximum of 30 points. Quantitative ultrasound of bone (QUS) is a method for assessing quality of bone which can be easily performed in nursing homes. Therefore, these two tests allowed to study the relationships between nutritional status and ultrasonic parameters of bone in 78 institutionalized women aged 86 +/- 6 years, living in 11 nursing homes around Lausanne (Switzerland). All were assessed by the MNA, had a measurement of the tricipital skin fold and of the grip strength. Functional status was evaluated by the scale "Activity of Daily Living" (ADL), and serum albumin level was measured when permitted. All had QUS of the calcaneus (with an Achilles, GE Lunar). The measured parameters are the Broadband Ultrasound Attenuation (BUA), attenuation of a band of ultrasonic frequencies through the medium, expressed in dB/MHz, and the Speed of Sound (SOS), speed of the ultrasounds through the medium, expressed in m/s. A third parameter, the stiffness index (SI), expressed as a percentage of the values obtained by the manufacturer in a young population and derived from BUA and SOS, was calculated automatically : SI = (0.67xBUA) + (0.28xSOS) - 420, expressed in percent compared to a young adult population (%YA). Fifteen percent of the women were undernourished and 58% were at risk of malnutrition. As expected, compared with the well-nourished minority, undernourished subjects had significant lower body mass index (BMI), tricipital skin fold (TSF), ADL score and albumin level (p < 0,01). The subjects "at risk of malnutrition" had significant lower BMI, ADL score (p < 0.01), tricipital skin fold and serum albumin (p < 0.05). Ultrasound parameters were low independently of the nutritional status. MNA score correlated significantly with tricipital skin fold (r = 0.508, p < 0.01), ADL (r = 0.538, p < 0.01) and albumin serum level (r = 0.409, p = 0.01). There was a trend for a correlation between the MNA and the ultrasound parameter BUA (r = 0.207, p = 0.07), whereas no correlation was found with SOS and SI. A multivariate analysis showed that tricipital skin fold and ADL explained 61% of the variance of the MNA. In conclusion, using simple and non invasive methods, this study showed that malnutrition and osteoporosis are frequent in institutionalized elderly persons in our country, and the ultrasound parameters are influenced by many others factors in addition to nutrition, especially at this age and in elderly residents of nursing homes.