Transcranial direct current stimulation improves myofascial pain syndrome and chronic fatigue.

Not available.

Developmental ecdysteroid titers and DNA puffs in larvae of two sciarid species, Rhynchosciara americana and Rhynchosciara milleri (Diptera: Sciaridae).

Ecdysteroid titers, developmental landmarks and the presence of prominent amplifying regions (DNA puffs) have been compared during late larval to pupal development in four groups of Rhynchosciara americana larvae and in R. americana and Rhynchosciara milleri. Three prominent DNA puffs (B2, C3 and C8) expand and regress sequentially on the rising phase of the 20-hydroxyecdysone (20E) titer in R. americana as a firm, cellular cocoon is being constructed. A sharp rise in 20E coincides with the regression of these puffs. The shape of the 20E curve is similar in R. milleri, a species that does not construct a massive cocoon, but the behavior of certain DNA puffs and their temporal relationship to the curve differs. Regions corresponding to B2 and C3 can be identified in R. milleri by banding pattern similarity with R. americana chromosomes and, in the case of B2, by hybridization to an R. americana probe. A B2 puff appears in R. milleri as the 20E titer rises but remains small in all gland regions. A puff similar to the R. americana C3 puff occurs in posterior gland cells of R. milleri (C3(Rm)) after the B2 puff, but this site did not hybridize to R. americana C3 probes. C3(Rm) incorporated (3)H-thymidine above background, but showed less post-puff DNA accumulation than C3 of R. americana. R. americana C8 probes hybridized to a more distal region of the R. milleri C chromosome that did not appear to amplify or form a large puff. These differences can be related to developmental differences, in particular differences in cocoon construction between the two species.

The mGluR5 positive allosteric modulator, CDPPB, ameliorates pathology and phenotypic signs of a mouse model of Huntington's disease.

Huntington's disease (HD) is an autosomal-dominant neurodegenerative disorder caused by a polyglutamine expansion in the amino-terminal region of the huntingtin protein (htt), leading to motor dysfunction, cognitive decline, psychiatric alterations, and death. The metabotropic glutamate receptor 5 (mGluR5) has been implicated in HD and we have recently demonstrated that mGluR5 positive allosteric modulators (PAMs) are neuroprotective in vitro. In the present study we demonstrate that the mGluR5 PAM, CDPPB, is a potent neuroprotective drug, in vitro and in vivo, capable of delaying HD-related symptoms. The HD mouse model, BACHD, exhibits many HD features, including neuronal cell loss, htt aggregates, motor incoordination and memory impairment. However, chronic treatment of BACHD mice with CDPPB 1.5 mg/kg s.c. for 18 weeks increased the activation of cell signaling pathways important for neuronal survival, including increased AKT and ERK1/2 phosphorylation and augmented the BDNF mRNA expression. CDPPB chronic treatment was also able to prevent the neuronal cell loss that takes place in the striatum of BACHD mice and decrease htt aggregate formation. Moreover, CDPPB chronic treatment was efficient to partially ameliorate motor incoordination and to rescue the memory deficit exhibited by BACHD mice. Importantly, no toxic effects or stereotypical behavior were observed upon CDPPB chronic treatment. Thus, CDPPB is a potential drug to treat HD, preventing neuronal cell loss and htt aggregate formation and delaying HD symptoms.

Metabotropic glutamate receptor 5 positive allosteric modulators are neuroprotective in a mouse model of Huntington's disease.

BACKGROUND AND PURPOSE: Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder caused by a polyglutamine expansion in the huntingtin protein. We have previously demonstrated that the cell signalling of the metabotropic glutamate receptor 5 (mGluR5) is altered in a mouse model of HD. Although mGluR5-dependent protective pathways are more activated in HD neurons, intracellular Ca²âº release is also more pronounced, which could contribute to excitotoxicity. In the present study, we aim to investigate whether mGluR5 positive allosteric modulators (PAMs) could activate protective pathways without triggering high levels of Ca²âº release and be neuroprotective in HD. EXPERIMENTAL APPROACH: We performed a neuronal cell death assay to determine which drugs are neuroprotective, Western blot and Ca²âº release experiments to investigate the molecular mechanisms involved in this neuroprotection, and object recognition task to determine whether the tested drugs could ameliorate HD memory deficit. KEY RESULTS: We find that mGluR5 PAMs can protect striatal neurons from the excitotoxic neuronal cell death promoted by elevated concentrations of glutamate and NMDA. mGluR5 PAMs are capable of activating Akt without triggering increased intracellular Ca²âº concentration ([Ca²âº]i ); and Akt blockage leads to loss of PAM-mediated neuroprotection. Importantly, PAMs' potential as drugs that may be used to treat neurodegenerative diseases is highlighted by the neuroprotection exerted by mGluR5 PAMs on striatal neurons from a mouse model of HD, BACHD. Moreover, mGluR5 PAMs can activate neuroprotective pathways more robustly in BACHD mice and ameliorate HD memory deficit. CONCLUSIONS AND IMPLICATIONS: mGluR5 PAMs are potential drugs that may be used to treat neurodegenerative diseases, especially HD.

Twelve chromatically opponent ganglion cell types in turtle retina.

The turtle retina has been extensively used for the study of chromatic processing mechanisms. Color opponency has been previously investigated with trichromatic paradigms, but behavioral studies show that the turtle has an ultraviolet (UV) channel and a tetrachromatic visual system. Our laboratory has been working in the characterization of neuronal responses in the retina of vertebrates using stimuli in the UV-visible range of the electromagnetic spectrum. In the present investigation, we recorded color-opponent responses from turtle amacrine and ganglion cells to UV and visible stimuli and extended our previous results that UV color-opponency is present at the level of the inner nuclear layer. We recorded from 181 neurons, 36 of which were spectrally opponent. Among these, there were 10 amacrine (5%), and 26 ganglion cells (15%). Morphological identification of color-opponent neurons was possible for two ganglion cell classes (G17 and G22) and two amacrine cell classes (A22 and A23b). There was a variety of cell response types and a potential for complex processing of chromatic stimuli, with intensity- and wavelength-dependent response components. Ten types of color opponency were found in ganglion cells and by adding previous results from our laboratory, 12 types of opponent responses have been found. The majority of the ganglion cells were R+UVBG- and RG+UVB-color-opponents but there were other less frequent types of chromatic opponency. This study confirms the participation of a UV channel in the processing of color opponency in the turtle inner retina and shows that the turtle visual system has the retinal mechanisms to allow many possible chromatic combinations.

Susceptibility-weighted imaging for the evaluation of patients with familial cerebral cavernous malformations: a comparison with t2-weighted fast spin-echo and gradient-echo sequences.

BACKGROUND AND PURPOSE: The T2-weighted gradient-echo (GRE) imaging is currently the gold standard MR imaging sequence for the evaluation of patients with cerebral cavernous malformation (CCM) lesions. We aimed to compare the sensitivity of susceptibility-weighted imaging (SWI) with T2-weighted fast spin-echo (FSE) and GRE imaging in assigning the number of CCM lesions in patients with the familial form of the disease. MATERIALS AND METHODS: We studied 15 patients (8 men, 7 women; mean age, 34 years) with familial CCM. All patients underwent MR imaging with the following sequences: T1-weighted spin echo, T2-weighted FSE, T2-weighted GRE, and SWI. Two neuroradiologists read the images regarding the number of lesions seen on each sequence. The final decisions were reached by consensus. The number of lesions on the different sequences was compared with analysis of variance, followed by a nonparametric Wilcoxon matched-pairs signed rank test. RESULTS: The number of lesions was higher on T2-weighted GRE than on T2-weighted FSE (P = .001). In addition, more lesions were seen on SWI than on T2-weighted GRE (P = .001) and FSE (P = .001) sequences. CONCLUSION: The sensitivity of SWI in assigning the number of CCM lesions in patients with the familial form of the disease is significantly higher than that of T2-weighted FSE and GRE sequences.

Effects of mercury intoxication on the response of horizontal cells of the retina of thraira fish (Hoplias malabaricus).

Methyl mercury (MeHg) is highly neurotoxic, affecting visual function in addition to other central nervous system functions. The effect of mercury intoxication on the amplitude of horizontal cell responses to light was studied in the retina of the fish Hoplias malabaricus. Intracellular responses were recorded from horizontal cells of fish previously intoxicated with MeHg by intraperitoneal injection (IP group) or by trophic exposure (T group). Only one retina per fish was used. The doses of MeHg chloride administered to the IP group were 0.01, 0.05, 0.1, 1.0, 2.0, and 6.0 mg/kg. The amplitudes of the horizontal cell responses were lower than control in individuals exposed to 0.01 (N = 4 retinas), 0.05 (N = 2 retinas) and 0.1 mg/kg (N = 1 retina), whereas no responses were recorded in the 1.0, 2.0, and 6.0 mg/kg groups. T group individuals were fed young specimens of Astyanax sp previously injected with MeHg corresponding to 0.75 (N = 1 retina), 0.075 (N = 8 retinas) or 0.0075 (N = 4 retinas) mg/kg fish body weight. After 14 doses, one every 5 days, the amplitude of the horizontal cell response was higher than control in individuals exposed to 0.075 and 0.0075 mg/kg, and lower in individuals exposed to 0.75 mg/kg. We conclude that intoxication with MeHg affects the electrophysiological response of the horizontal cells in the retina, either reducing or increasing its amplitude compared to control, and that these effects are related to the dose and/or to the mode of administration.

Effects of mercury intoxication on the response of horizontal cells of the retina of thraira fish (Hoplias malabaricus)

Methyl mercury (MeHg) is highly neurotoxic, affecting visual function in addition to other central nervous system functions. The effect of mercury intoxication on the amplitude of horizontal cell responses to light was studied in the retina of the fish Hoplias malabaricus. Intracellular responses were recorded from horizontal cells of fish previously intoxicated with MeHg by intraperitoneal injection (IP group) or by trophic exposure (T group). Only one retina per fish was used. The doses of MeHg chloride administered to the IP group were 0.01, 0.05, 0.1, 1.0, 2.0, and 6.0 mg/kg. The amplitudes of the horizontal cell responses were lower than control in individuals exposed to 0.01 (N = 4 retinas), 0.05 (N = 2 retinas) and 0.1 mg/kg (N = 1 retina), whereas no responses were recorded in the 1.0, 2.0, and 6.0 mg/kg groups. T group individuals were fed young specimens of Astyanax sp previously injected with MeHg corresponding to 0.75 (N = 1 retina), 0.075 (N = 8 retinas) or 0.0075 (N = 4 retinas) mg/kg fish body weight. After 14 doses, one every 5 days, the amplitude of the horizontal cell response was higher than control in individuals exposed to 0.075 and 0.0075 mg/kg, and lower in individuals exposed to 0.75 mg/kg. We conclude that intoxication with MeHg affects the electrophysiological response of the horizontal cells in the retina, either reducing or increasing its amplitude compared to control, and that these effects are related to the dose and/or to the mode of administration.

Raman spectra of deuteriated taurine single crystals.

The polarized Raman spectra of partially deuteriated taurine [(ND3+)0.65(NH3+)0.35(CH2)2SO3-] crystals from x(zz)x and x(zy)x scattering geometries of the Ag and Bg irreducible representations of the factor group C2h are reported. The temperature-dependent Raman spectra of partially deuteriated taurine do not reveal any evidence of the structural phase transition undergone by normal taurine at about 250 K, but an anomaly observed in the 180 cm-1 band at approximately 120 K implies a different dynamic for this band (which is involved in a pressure-induced phase transition) in the deuteriated crystal.

Colour vision and contrast sensitivity losses of mercury intoxicated industry workers in Brazil.

We evaluated vision loss in workers from fluorescent lamp industries (n=39) who had retired due to intoxication with mercury vapour and had been away from the work situation for several years (mean=6.32 years). An age-matched control group was submitted to the same tests for comparison. The luminance contrast sensitivity (CSF) was measured psychophysically and with the sweep visual evoked potential (sVEP) method. Chromatic red-green and blue-yellow CSFs were measured psychophysically. Colour discrimination was assessed with the Farnsworth-Munsell 100-hue test, Lanthony D-15d test and Cambridge Colour Vision Test. Patient data showed significantly lower scores in all colour tests compared to controls (p<.001). The behavioural luminance CSF of the patients was lower than that of controls (p<.001 at all frequencies tested). This result was confirmed by the electrophysiologically measured sweep VEP luminance CSF except at the highest frequencies-a difference that might be related to stimulus differences in the two situations. Chromatic CSFs were also statistically significantly lower for the patients than for the controls, for both chromatic equiluminant stimuli: red-green (p<.005) and blue-yellow (p<.04 for all frequencies, except 2 cycles per degree (cpd), the highest spatial frequency tested) spatial gratings. We conclude that exposure to elemental mercury vapour is associated with profound and lasting losses in achromatic and chromatic visual functions, affecting the magno-, parvo- and koniocellular visual pathways.

Contrast sensitivity threshold measured by sweep-visual evoked potential in term and preterm infants at 3 and 10 months of age.

Although healthy preterm infants frequently seem to be more attentive to visual stimuli and to fix on them longer than full-term infants, no difference in visual acuity has been reported compared to term infants. We evaluated the contrast sensitivity (CS) function of term (N = 5) and healthy preterm (N = 11) infants at 3 and 10 months of life using sweep-visual evoked potentials. Two spatial frequencies were studied: low (0.2 cycles per degrees, cpd) and medium (4.0 cpd). The mean contrast sensitivity (expressed in percentage of contrast) of the preterm infants at 3 months was 55.4 for the low spatial frequency (0.2 cpd) and 43.4 for the medium spatial frequency (4.0 cpd). At 10 months the low spatial CS was 52.7 and the medium spatial CS was 9.9. The results for the term infants at 3 months were 55.1 for the low spatial frequency and 34.5 for the medium spatial frequency. At 10 months the equivalent values were 54.3 and 14.4, respectively. No difference was found using the Mann-Whitney rank sum T-test between term and preterm infants for the low frequency at 3 or 10 months or for the medium spatial frequency at 3 or 10 months. The development of CS for the medium spatial frequency was equally fast for term and preterm infants. As also observed for visual acuity, CS was equivalent among term and preterm infants, suggesting that visual experience does not modify the development of the primary visual pathway. An earlier development of synapses in higher cortical visual areas of preterm infants could explain the better use of visual information observed behaviorally in these infants.

[Assessment of the response to reduced treatment schemes for vivax malaria]. / Avaliação da resposta aos esquemas de tratamento reduzidos para malária vivax.

Relapses may occur with long standard treatment of vivax malaria, and these are caused by incomplete patient's compliance. The use of reduced schedules may further better patient compliance, while maintaining the same efficacy, tolerance and minimal adverse reactions. The objective of this study was to test two schedules with reduced doses of chloroquine for vivax malaria and comparing these with the classical schedule. The authors studied 120 outpatients, with vivax malaria, aged over 12 years, submitted to three therapeutic schemes: scheme I: chloroquine phosphate (150 mg) in a dose of 25mg/kg/day for three days (10mg/kg/ day in the first day, 7.5mg/kg/day in the second and third day), plus primaquine (15 mg) in a dose of 0.25mg/kg/day for fourteen days; scheme II: chloroquine, in a single dose of 10mg/kg, plus primaquine in a dose of 0.5mg/kg/day for seven days; scheme III: chloroquine, 10mg/kg in a single dose plus primaquine in a dose 0.5mg/kg/ day for five days. The clinical response to all three therapeutic schemes was satisfactory. The disappearance of malarial symptoms occurred after a maximum 96 hours of treatment, while the asexual parasitaemia clearance occurred within 72 hours, in all therapeutic schemes.

Ultraviolet colour opponency in the turtle retina.

We have examined the functional architecture of the turtle Pseudemys scripta elegans retina with respect to colour processing, extending spectral stimulation into the ultraviolet, which has not been studied previously in the inner retina. We addressed two questions. (i) Is it possible to deduce the ultraviolet cone spectral sensitivity function through horizontal cell responses? (ii) Is there evidence for tetrachromatic neural mechanisms, i.e. UV/S response opponency? Using a constant response methodology we have isolated the ultraviolet cone input into the S/LM horizontal cell type and described it in fine detail. Monophasic (luminosity), biphasic L/M (red-green) and triphasic S/LM (yellow-blue) horizontal cells responded strongly to ultraviolet light. The blue-adapted spectral sensitivity function of a S/LM cell peaked in the ultraviolet and could be fitted to a porphyropsin cone template with a peak at 372 nm. In the inner retina eight different combinations of spectral opponency were found in the centre of the receptive field of ganglion cells. Among amacrine cells the only types found were UVSM-L+ and its reverse. One amacrine and four ganglion cells were also opponent in the receptive field surround. UV/S opponency, seen in three different types of ganglion cell, provides a neural basis for discrimination of ultraviolet colours. In conclusion, the results strongly suggest that there is an ultraviolet channel and a neural basis for tetrachromacy in the turtle retina.

Tetrachromatic input to turtle horizontal cells.

Recent physiological experiments support behavioral and morphological evidence for a fourth type of cone in the turtle retina, maximally sensitive in the ultraviolet (UV). This cone type has not yet been included in the models proposed for connectivity between cones and horizontal cells. In this study, we examined the inputs of UV, S, M, and L cones to horizontal cells. We used the high-resolution Dynamic Constant Response Method to measure the spectral sensitivity of horizontal cells without background light and after adaptation to UV, blue (B), green (G), and red (R) light. We concluded the following: (1) Tetrachromatic input to a Y/B horizontal cell was identified. The spectral-sensitivity curves of the cell in three of the adaptation conditions were well represented by L-, M-, and S-cone functions. Adaptation to blue light revealed a peak at 372 nm, the same wavelength location as that determined behaviorally in the turtle. A porphyropsin template could be closely fitted to the sensitivity band in that region, strong evidence for input from a UV cone. (2) The spectral-sensitivity functions of R/G horizontal cells were well represented by the L- and M-cone functions. There was no indication of UV- or S-cone inputs into these cells. (3) The spectral sensitivities of the monophasic horizontal cells were dominated by the L cone. However, the shape of the spectral-sensitivity function depended on the background wavelength, indicating secondary M-cone input. Connectivity models of the outer retina that predict input from all cone types are supported by the finding of tetrachromatic input into Y/B horizontal cells. In contrast, we did not find tetrachromatic input to R/G and monophasic horizontal cells. Chromatic adaptation revealed the spectral-sensitivity function of the turtle UV cone peaking at 372 nm.

[Comparative study between larval surveys and ovitraps to monitor populations of Aedes aegypti]. / Comparação entre pesquisa larvária e armadilha de oviposição, para detecção de Aedes aegypti.

This study compares two techniques for detecting the presence of Aedes aegypti: larval surveys and the oviposition trap. In two areas of the municipality of Salvador, Bahia, Brazil were investigated 5,026 households. Larval surveys and oviposition traps were used simultaneously in these households. Different positivity levels (larvae and/or eggs) were detected between and within the two areas. However, only the use of the oviposition trap detected a significant statistical difference between the areas (z = 9,520, p < 0.001). Comparison of the Breteau, Household and Oviposition Indices reveals greater power of detection of positivity in the oviposition trap. There were prevalence ratios of positivity for oviposition trap of 3.4 and 2.1 (for areas 1 and 2 respectively) when compared with larval surveys. The oviposition trap proved to be an economical and operationally viable method, and the most effective in the surveillance of this species.

UV responses in the retina of the turtle.

To study processing of UV stimuli in the retina of the turtle, Trachemys dorbignii, we recorded intracellular responses to spectral light from 89 cells: 54 horizontal (47 monophasic, five (R/G) biphasic and two (Y/B) triphasic), 14 bipolar, 12 amacrine, and nine ganglion cells. Spectral sensitivities were measured with monochromatic flashes or with the dynamic constant response method in dark or chromatic adapted states. Stray light and second-order harmonics were also measured. (1) All cells responded to UV stimuli, although none had maximum sensitivity in the UV. (2) Most horizontal, bipolar, and amacrine cells had red-peaked spectral sensitivities. (3) Red adaptation of all monophasic horizontal cells indicated a single red input, except one that had additional peaks in the blue and UV. (4) Responses of biphasic and triphasic horizontal cells to UV light were always hyperpolarizing. Opposition between hyperpolarizing and depolarizing responses at long wavelengths indicates that UV responses were not due to the beta band of red receptors. (5) An unstained spectrally opponent bipolar cell hyperpolarized in the center to green light and antagonistically depolarized in the surround to UV, blue, and green flashes, but hyperpolarized to red. (6) All dark-adapted amacrine cells were red-peaked monophasic cells, but red adaptation broadened their spectral-sensitivity curves or displaced their peaks. An A15, an A18, and an A24 wide-field amacrine cell were stained. (7) A G15 bistratified ganglion cell is shown here for the first time to be spectrally opponent. This UVB/RG cell depolarized to UV and blue and hyperpolarized to red and green. It differs from previously reported turtle ganglion cells in being color opponent in the entire field, not only in the surround, and in showing spatial opponency.

[Case-control design in cardiovascular disease epidemiology. II--Analysis of data]. / Metodologia caso-controle em epidemiologia de doenças cardiovasculares. II--Análise de dados.

The wide spread distribution of statistical software recommended for multivariate analysis as well as the ease in handling it can lead the users into adopting wrong measures if they do not pay attention to the theoretical principles behind those methods. With a view to bringing out some of these principles some steps for the data analysis of a case-control study undertaken in the city of S. Paulo-Brazil from March, 1993 to February, 1994 in order to test the association between diabetes mellitus and ischaemic heart disease after adjusting for potential confounders and/or modifiers of effect are presented. Methodologic issues are emphasized in the development of four steps: a) the data bank structure: b) the calculation of statistical power; c) the definition of variables strata and codification and d) the choice of the logistic regression method.

Reproducibility of alkaline antigens of Leishmania major-like and Leishmania (V.) braziliensis evaluated by IgG-ELISA. Comparison of antigens added of a protein inhibitor (PMSF) or not.

This paper deals with the analysis of 10 batches of L.major-like and L. (V.) braziliensis antigens added or not of a proteases inhibitor evaluated by means of an IgG-ELISA on three consecutive days using positive standard sera from patients with diagnosis of American Leishmaniasis previously tested for the presence of IgG antibodies by means of ELISA. The statistical analysis showed that for L. (V.) braziliensis the PMSF-containing antigen did not show any difference among batches or days of testing; the L. (V.) braziliensis antigen without PMSF showed statistical significance for differences among batches and a two-way ANOVA showed significant differences between antigens. L.major-like antigen prepared with or without PMSF showed differences among batches; all 3 days of testing displayed differences for the PMSF antigen but only for days 1 and 2 for the antigen without inhibitor. A two-way ANOVA showed differences among batches of the antigens but not for antigens with and without the protein inhibitor. According to the statistical analysis the L.major-like antigen added or not of PMSF has shown that it is the choice antigen for mucocutaneous leishmaniasis serology.

IDDM and milk consumption. A case-control study in São Paulo, Brazil.

OBJECTIVE: To test the hypothesis that breast-feeding is a protective factor against IDDM and that early exposure to cow's milk is a risk factor for the disease. RESEARCH DESIGN AND METHODS: A case-control study was conducted in São Paulo, Brazil. A total of 346 diabetic children, aged < 18 years, were identified in two institutions in the city of São Paulo. Duration of exclusive breast-feeding and age of introduction to cow's milk products in infant diet were compared with 346 sex-, age-, and neighborhood-matched control children. All comparisons between diabetic and control children were done using paired tests. RESULTS: Statistically significant differences were found for the duration of exclusive breast-feeding (P = 0.007) and for the age of introduction to cow's milk products (P = 0.047). Control children had a longer time of exclusive breast-feeding and had received cow's milk later in their diet than the case children. CONCLUSIONS: The results suggest that a shorter duration of exclusive breast-feeding is a risk factor for IDDM (odds ratio [OR] 2.13; 95% CI 1.8-3.55) and that the introduction to cow's milk products before age 8 days is a risk factor for the disease.

Evaluation of Leishmania antigens preparation and storage for use in enzyme immunoassays.

The influence of time and temperature on the storage of an alkaline antigen of L. major-like and L.(V.) braziliensis promastigotes added or not of a proteases inhibitor (PMSF) was evaluated by means of an IgG-ELISA. Antibodies in assays using L. major-like antigen stored at -20 degrees C for 6 months had a statistically lower geometric mean titer (GMT) and different 95% confidence interval limits (CL) than antigens stored otherwise, as assessed by the "t" statistic. The PMSFL. major-like antigen after storage for 6 months at a temperature of 4 degrees C had the same GMT and 95% CL displayed at time zero as well as when storage for 4 and 6 months at -20 degrees C. Significant differences were not found when L.(V.) braziliensis antigens were stored at times and temperatures mentioned; the PMSF antigen stored for 2 months at -70 degrees C resulted in a lower serum GMT and 95% CL than any other, as assessed by the "t" statistic. Antigen performance did not show any statistical difference associated to the addition of PMSF within the same species; the largest difference between antigens was that between PMSF-L. (V.) braziliensis and L. major-like without PMSF.