Sequence-Specific DNA Binding by Noncovalent Peptide-Azocyclodextrin Dimer Complex as a Suitable Model for Conformational Fuzziness.

Transcription factors are proteins lying at the endpoint of signaling pathways that control the complex process of DNA transcription. Typically, they are structurally disordered in the inactive state, but in response to an external stimulus, like a suitable ligand, they change their conformation, thereby activating DNA transcription in a spatiotemporal fashion. The observed disorder or fuzziness is functionally beneficial because it can add adaptability, versatility, and reversibility to the interaction. In this context, mimetics of the basic region of the GCN4 transcription factor (Tf) and their interaction with dsDNA sequences would be suitable models to explore the concept of conformational fuzziness experimentally. Herein, we present the first example of a system that mimics the DNA sequence-specific recognition by the GCN4 Tf through the formation of a non- covalent tetra-component complex: peptide-azoß-CyD(dimer)-peptide-DNA. The non-covalent complex is constructed on the one hand by a 30 amino acid peptide corresponding to the basic region of GCN4 and functionalized with an adamantane moiety, and on the other hand an allosteric receptor, the azoCyDdimer, that has an azobenzene linker connecting two ß-cyclodextrin units. The azoCyDdimer responds to light stimulus, existing as two photo-states: the first thermodynamically stable with an E:Z isomer ratio of 95:5 and the second obtained after irradiation with ultraviolet light, resulting in a photostationary state with a 60:40 E:Z ratio. Through electrophoretic shift assays and circular dichroism spectroscopy, we demonstrate that the E isomer is responsible for dimerization and recognition. The formation of the non-covalent tetra component complex occurs in the presence of the GCN4 cognate dsDNA sequence ('5-..ATGA cg TCAT..-3') but not with ('5-..ATGA c TCAT..-3') that differs in only one spacing nucleotide. Thus, we demonstrated that the tetra-component complex is formed in a specific manner that depends on the geometry of the ligand, the peptide length, and the ds DNA sequence. We hypothesized that the mechanism of interaction is sequential, and it can be described by the polymorphism model of static fuzziness. We argue that chemically modified peptides of the GCN4 Tf are suitable minimalist experimental models to investigate conformational fuzziness in protein-DNA interactions.

Periconceptional undernutrition modifies endocrine profiles and hepatic gene expression in sheep.

This study investigated whether a 22-day period of undernutrition (half maintenance) could affect maternal endocrine responses and liver gene expression during early pregnancy (day 7). Thirty-five ewes were fed 1.5 (n = 15) or 0.5 (n = 20) their maintenance requirements and slaughtered on day 7 of the oestrus cycle or pregnancy (oestrus = day 0). Insulin, IGF, leptin and non-esterified fatty acids (NEFA) were determined on days -14, 0 and 7. Transcripts of the IGF family and adipokines receptors were determined in the liver by real-time RT-PCR. Underfed animals presented lower body weight and body condition, greater plasma concentration of NEFA, and lower plasma concentrations of leptin, insulin and IGF1 compared to adequately fed animals. Underfed ewes presented greater hepatic expression of IGFBP2 than well-fed ewes, but tended to have lesser expression of IGFBP5. While no effect of undernutrition on IGFBP4 and ADIPOR2 mRNA expressions was observed, they were increased by pregnancy in underfed animals. This study shows that undernutrition modifies endocrine profiles and hepatic gene expression of IGFBP2 and 5. The pregnancy status increased hepatic gene expression of IGFBP4 and ADIPOR2 mRNA in undernourished ewes.

Biomechanical framework for the inverse dynamic analysis of swimming using hydrodynamic forces from swumsuit.

This study aims to integrate an open-source software capable of estimating hydrodynamic forces solely from kinematic data with a full-body biomechanical model of the human body to enable inverse dynamic analyses of swimmers. To demonstrate the methodology, intersegmental forces and joint torques of the lower limbs were computed for a six-beat front crawl swimming motion, acquired at LABIOMEP-UP. The hydrodynamic forces obtained compare well with existing numerical literature. The intersegmental forces and joint torques obtained increase from distal to proximal joints. Overall, the results are consistent with the limited literature on swimming biomechanics, which provides confidence in the presented methodology.

Divergence and biogeography of the recently evolved Macaronesian red Festuca (Gramineae) species inferred from coalescence-based analyses.

Studying the biogeography and the phylogeography of the endemic Macaronesian red Festuca species (Loliinae, Poaceae) is of prime interest in understanding the speciation and colonization patterns of recently evolved groups in oceanic archipelagos. Coalescence-based analyses of plastid trnLF sequences were employed to estimate evolutionary parameters and to test different species-history scenarios that model the pattern of species divergence. Bayesian IM estimates of species divergence times suggested that ancestral lineages of diploid Macaronesian and Iberian red fescues could have diverged between 1.2 and 1.57 Ma. When empirical data were compared to coalescence-based simulated distributions of discordance and p-distance statistics, two species-history models were chosen in which the first branching lineage derived in Canarian Festuca agustinii. Its sister lineage could have involved a recent polytomy leading to the Madeiran Festuca jubata, the Azorean Festuca francoi + Festuca petraea and the continental Festuca rivularis lineages (Canarian model) or the sequential branching of lineages leading to F. jubata and finally to the sister clades of F. rivularis and F. francoi + F. petraea (Sequential model). Nested clade phylogeographic analysis (NCPA) and a first adapted host-parasite co-evolutionary ParaFit method were used to detect the phylogeographic signal. NCPA inferred long-distance colonizations for the entire diploid red Festuca complex, but allopatric-fragmentation and isolation-by-distance (IBD) patterns were inferred within archipelagos. In addition, the ParaFit method suggested a generalized pattern of a stepping-stone model at all hierarchical levels. Maximum-likelihood-based dispersal-extinction-cladogenesis (DEC) models were superimposed on the Sequential model species tree. The three-independent-colonization (3IC) model was the best supported biogeographic scenario, concurring with previous analysis based on multilocus AFLP data.

Selective Lesioning of Nuclear Factor-κB Activated Cells in the Nucleus Accumbens Shell Attenuates Alcohol Place Preference.

Nuclear factor κ-light chain enhancer of activated B cells (NF-κB) is a transcription factor commonly associated with innate immunity and is activated by infection and inflammation. NF-κB has recently gained attention as a mediator of complex psychiatric phenomena such as stress and addiction. In regards to alcohol, most research on NF-κB has focused on neurotoxicity and few studies have explored the role of NF-κB in alcohol reward, reinforcement, or consumption. In these studies, we used conditioned place preference to assess the activity of NF-κB in response to rewarding doses of alcohol. To measure NF-κB activity we used a line of transgenic mice that express the LacZ gene under the control of an NF-κB-regulated promoter. In these animals, staining for ß-galactosidase (ß-gal) identifies cells in which NF-κB has been activated. We then used the Daun02 inactivation method to specifically silence NF-κB-expressing cells during place preference conditioning. Daun02 is an inactive prodrug that is converted to the inhibitory molecule daunorubicin by ß-gal. After alcohol place conditioning, we observed increased ß-gal staining in the nucleus accumbens (NAC) shell and dorsal raphe nucleus, and found that disruption of NF-κB-expressing cells using Daun02 attenuated the development of alcohol place preference when infused into the NAC shell following conditioning sessions. We found this effect to be regionally and temporally specific. These results suggest that, in addition to its role in alcohol-induced neurotoxicity, NF-κB mediates the development of alcohol place preference via its actions in the NAC shell.

Organochlorine compounds and stable isotopes indicate bottlenose dolphin subpopulation structure around the Iberian Peninsula.

Isotopic signatures and organochlorine pollutant loads of organisms reflect the characteristics of the waters in which they live and feed. To investigate population structure of bottlenose dolphins around the Iberian Peninsula we determined delta(13)C and delta(15)N in the skin and organochlorine (OC) levels in the blubber of stranded bottlenose dolphins inhabiting the Mediterranean (Catalonia, Valencia and Balearic Islands) and adjacent Atlantic waters (Huelva and Portugal). OC levels were high in all regions, reflecting the predatory habits of the species, its coastal distribution and the existence of intense agricultural and industrial activity throughout the region. PCB congeners showed a gradient from the relatively more chlorinated forms to those that are less so, and followed a northeast to northwest direction across the Iberian Peninsula. This suggests that PCB inputs are more recent in the temperate latitudes of the eastern Atlantic Ocean than in the western Mediterranean Sea. Comparatively, OC ratios and isotopic signatures proved to be more efficient ways of discriminating groups than did raw OC concentrations. Significant differences in delta(13)C and in PCB congener profiles indicate that dolphins from the Atlantic and the Mediterranean do not intermingle. In addition, the two Atlantic groups differed in delta(15)N signature, tDDT concentration, DDT/PCB ratio and the PCB congener profile, which also suggests some degree of isolation between them. In the Mediterranean, dolphins from Catalonia and Valencia were indistinguishable, suggesting a common distribution area. However, dolphins from the Balearic Islands differed from those of the Peninsula in their DDT/PCB ratio and from all the other sample groups in their PCB congener profiles, which supports the hypothesis that the deep waters between the Islands and the Peninsula represent an effective barrier for the species.

[In-vitro activity of two hybrid synthetic peptides having antimicrobial activity against mycobacteria]. / Sensibilidad in vitro de micobacterias a dos péptidos sintéticos híbridos con actividad antimicrobiana.

The increase in both Mycobacterium tuberculosis human clinical isolates resistant to the essential drugs and cases of disseminated micobacteriosis due to Mycobacterium avium Complex, underlines the need to investigate new antimicobacterial agents. The antimicrobial peptides are a new group of active antibiotics with a particular mechanism of action. Some of them, like cecropin and melittin, isolated from insects, have demonstrated good in vitro activity against Gram-positive and Gram-negative bacteria. Synthetic hybrids of those peptides have been more active than individual peptides. In this study, the in vitro activity of two hybrid synthetic peptides from melittin and cecropin against M. tuberculosis, M. avium Complex, Mycobacterium fortuitum and Mycobacterium smegmatis has been evaluated. The minimal inhibitory concentration was determined by using the broth macrodilution technique. The minimal bactericide concentration in Lowenstein Jensen medium was then obtained. The peptides studied were active, in vitro, against M. smegmatis, but they did not show any activity against the other mycobacteria analyzed.

Development of a Nonionic Azobenzene Amphiphile for Remote Photocontrol of a Model Biomembrane.

We report the synthesis and characterization of a simple nonionic azoamphiphile, C12OazoE3OH, which behaves as an optically controlled molecule alone and in a biomembrane environment. First, Langmuir monolayer and Brewster angle microscopy (BAM) experiments showed that pure C12OazoE3OH enriched in the (E) isomer was able to form solidlike mesophase even at low surface pressure associated with supramolecular organization of the azobenzene derivative at the interface. On the other hand, pure C12OazoE3OH enriched in the (Z) isomer formed a less solidlike monolayer due to the bent geometry around the azobenzene moiety. Second, C12OazoE3OH is well-mixed in a biological membrane model, Lipoid s75 (up to 20%mol), and photoisomerization among the lipids proceeded smoothly depending on light conditions. It is proposed that the cross-sectional area of the hydroxyl triethylenglycol head of C12OazoE3OH inhibits azobenzenes H-aggregation in the model membrane; thus, the tails conformation change due to photoisomerization is transferred efficiently to the lipid membrane. We showed that the lipid membrane effectively senses the azobenzene geometrical change photomodulating some properties, like compressibility modulus, transition temperature, and morphology. In addition, photomodulation proceeds with a color change from yellow to orange, providing the possibility to externally monitor the system. Finally, Gibbs monolayers showed that C12OazoE3OH is able to penetrate the highly packing biomembrane model; thus, C12OazoE3OH might be used as photoswitchable molecular probe in real systems.

Gestation-related gene expression and protein localization in endometrial tissue of Suffolk and Cheviot ewes at gestation Day 19, after transfer of Suffolk or Cheviot embryos.

The objective of this study was to investigate the gene expression of progesterone and estrogen receptor α (PR, ERα), insulin-like growth factor (IGF) 1, IGF-2, their receptor (IGFR1), IGF-binding proteins (BP) 1 to 6, insulin receptor, adiponectin receptors (AdipoR1/2), cyclooxygenase 2 (PTGS2), mucin 1 and to localize PR, ERα, IGF-1, IGFR1, PTGS2, and proliferating cellular nuclear antigen (PCNA) in the endometrium of pregnant (Day 19) Suffolk and Cheviot ewes carrying Suffolk and Cheviot embryos transferred within and reciprocally between breeds. Gene expression was determined by real-time quantitative polymerase chain reaction (RT-qPCR), and antigen determination was measured by immunohistochemistry in the luminal epithelium (LE), superficial and deep glands (SG, DG, respectively) and superficial and deep stroma. Gene expression of PR, IGF-1, IGFBP2, and IGFBP5 was higher in Suffolk than that in Cheviot ewes (P < 0.05). Greater abundance of IGF-2 and IGBP3 expression was found in Cheviot ewes carrying Cheviot embryos than Cheviot ewes carrying Suffolk embryos (P < 0.05). No staining for PR and ERα was observed in the LE, very scarce staining in SG and DG, whereas positive staining was observed in both superficial and deep stroma. No differences were found for PR staining, but Cheviot ewes had higher ERα staining intensity than Suffolk ewes (P < 0.05). Positive staining for IGF-1 was observed in all cell types except DG, and staining of IGFR1 was observed in all cell types. No differences among groups in staining were found for IGF-1 or IGFR1 in any cell type. Positive staining of PTGS2 was observed in LE and SG in all groups. An interaction between ewe and embryo breed affected PTGS2 staining (P < 0.05), whereby Cheviot ewes carrying Suffolk embryos had a lower PTGS2 staining than Suffolk ewes carrying Suffolk embryos. Positive staining of PCNA was found in LE and SG. Suffolk ewes carrying Suffolk embryos showed lower PCNA immunostaining than Cheviot ewes carrying Suffolk embryos (P < 0.05), whereas no differences were observed in ewes carrying Cheviot embryos. This study showed that gestation-related protein expression in the endometrium of Suffolk and Cheviot ewes is affected by both ewe and embryo breed at Day 19 of pregnancy.

Resistance to HSP90 inhibition involving loss of MCL1 addiction.

Inhibition of the chaperone heat-shock protein 90 (HSP90) induces apoptosis, and it is a promising anti-cancer strategy. The mechanisms underpinning apoptosis activation following HSP90 inhibition and how they are modified during acquired drug resistance are unknown. We show for the first time that, to induce apoptosis, HSP90 inhibition requires the cooperation of multi BH3-only proteins (BID, BIK, PUMA) and the reciprocal suppression of the pro-survival BCL-2 family member MCL1, which occurs via inhibition of STAT5A. A subset of tumour cell lines exhibit dependence on MCL1 expression for survival and this dependence is also associated with tumour response to HSP90 inhibition. In the acquired resistance setting, MCL1 suppression in response to HSP90 inhibitors is maintained; however, a switch in MCL1 dependence occurs. This can be exploited by the BH3 peptidomimetic ABT737, through non-BCL-2-dependent synthetic lethality.

Mapping of arsenic content and distribution in groundwater in the southeast Pampa, Argentina.

The presence and spatial distribution of groundwater arsenic was evaluated in an area of approximately 6000 square kilometers that extends along the southeast border of the subhumid pampa plains of southeast Buenos Aires Province, Argentina. Groundwater constitutes the only easily exploitable source of water for the large rural and suburban population in the area, both for human consumption and for use in agricultural and livestock production. In the study area, 56.3 percent of water samples had seriously elevated arsenic levels (0.06 to 0.5 milligrams per liter [mg/L]), constituting a risk for human consumption and agricultural and livestock use. In 27.2 percent of the samples, arsenic content ranged from just below the World Health Organization-recommended maximum level of 0.01 mg/L to 0.05 mg/L. Only in 16.5 percent of the samples did the water contain no or very low concentrations. The contamination of domestic water supplies in the study area constitutes a serious water quality problem since this element has been identified as the cause of a number of health problems, including cancer.

Photoluminescence studies of a perceived white light emission from a monolithic InGaN/GaN quantum well structure.

In this work we demonstrate by photoluminescence studies white light emission from a monolithic InGaN/GaN single quantum well structure grown by metal organic chemical vapour deposition. As-grown and thermally annealed samples at high temperature (1000 °C, 1100 °C and 1200 °C) and high pressure (1.1 GPa) were analysed by spectroscopic techniques, and the annealing effect on the photoluminescence is deeply explored. Under laser excitation of 3.8 eV at room temperature, the as-grown structure exhibits two main emission bands: a yellow band peaked at 2.14 eV and a blue band peaked at 2.8 eV resulting in white light perception. Interestingly, the stability of the white light is preserved after annealing at the lowest temperature (1000 °C), but suppressed for higher temperatures due to a deterioration of the blue quantum well emission. Moreover, the control of the yellow/blue bands intensity ratio, responsible for the white colour coordinate temperatures, could be achieved after annealing at 1000 °C. The room temperature white emission is studied as a function of incident power density, and the correlated colour temperature values are found to be in the warm white range: 3260-4000 K.

Demonstration of reduced in vivo surface expression of activating mutant thyrotrophin receptors in thyroid sections.

OBJECTIVE: Thyroid function and growth are controlled by TSH. Hyperthyroidism can be due to Graves' Disease (GD), in which thyroid-stimulating antibodies mimic TSH, or gain-of-function mutations in the TSH receptor (TSHR). These activating mutations have poor surface expression when assessed in non-thyroidal cells in vitro but nothing is known of their in vivo behaviour. Several TSHR antibodies have been produced but none has been applied to thyroid paraffin sections. This study aimed to develop a technique suitable for use on paraffin sections and apply it to investigate TSHR expression in thyroids harbouring activating TSHR germline mutations compared with normal and GD thyroids. DESIGN AND METHODS: Immunocytochemistry coupled with antigen retrieval, using a spectrum of antibodies to the TSHR, was applied to paraffin sections of GD thyroid tissue. Subsequently, TSHR immunoreactivity was examined in three normal thyroids, three patients with GD and three patients with familial hyperthyroidism, due to different gain-of-function TSHR germline mutations, using the optimised protocol. RESULTS: Two antibodies, A10 and T3-495, to the extracellular domain (ECD) and membrane spanning region (MSR) of the TSHR respectively, produced specific basolateral staining of thyroid follicular cells. In normal and GD thyroids, basolateral staining with T3-495 was generally more intense than with A10, suggesting a possible surfeit of MSR over ECD. Graves' Disease thyroids have more abundant TSHR than normal glands. In contrast, thyroids harbouring gain-of-function mutations have the lowest expression in vivo, mirroring in vitro findings. CONCLUSIONS: The development of an immunocytochemical method applicable to paraffin sections has demonstrated that different molecular mechanisms causing hyperthyroidism result in the lowest (mutation) and highest (autoimmunity) levels of receptor at the thyrocyte surface.

Quality assessment of smear microscopy for acid-fast bacilli in the Argentine tuberculosis laboratory network, 1983-2001.

SETTING: Tuberculosis Laboratory Network, Argentina. OBJECTIVES: 1) To evaluate the technical quality of smear microscopy for acid-fast bacilli (AFB) supervised in 1983-2001, and 2) to analyse the effect of procedural errors on the results. DESIGN: Registers of technical evaluation results for AFB microscopy were analysed. The quality of specimens, smears, staining and readings were evaluated, as was the relationship between these parameters. RESULTS: The proportion of good quality specimens was considered acceptable. A direct relationship was demonstrated between positivity in results and mucopurulent sputum. The proportion of thin smears was relatively high. Positivity and bacillary count were lower in thin smears. Staining quality was considered good. The average agreement in readings throughout the country was 98%. Nevertheless, the false-positive rate was considered significant, and 46% of false-positive results were associated with defective staining. CONCLUSIONS: The technical quality and agreement in the laboratory network were satisfactory. Nevertheless, improvements need to be made in the following: the quality of the smears, staining and reading, coverage, decentralisation of supervision, the slide selection method and data registration. Operational research on the storage and preservation of slides is also necessary.

Evaluation of the diagnostic value of measuring IgG, IgM and IgA antibodies to the recombinant 16-kilodalton antigen of mycobacterium tuberculosis in childhood tuberculosis.

OBJECTIVE: To evaluate the usefulness of the recombinant 16-kDa antigen (re-Ag16) of Mycobacterium tuberculosis in the serodiagnosis of tuberculosis (TB) in children. MATERIALS: Seventy-four children with active TB, 49 apparently healthy contact children and 149 children suffering from non-mycobacterial diseases were evaluated. Detection of anti 16-kDa antigen IgG, IgM and IgA was performed by enzyme-immunoassay. RESULTS: An increased mean antibody response to re-Ag16 was observed in contact children compared with non-mycobacterial disease patients (IgG assay: 89.1 enzymatic units [eu] vs. 40.8 eu; IgM assay: 64.7 eu vs. 38.1 eu; IgA assay: 138.2 eu vs. 78.2 eu for contact children and non-mycobacterial disease patients, respectively), indicating that anti-16-kDa antibodies could be elevated in response to infections even without clinically apparent TB. Setting the specificity as the 95th percentile of the contact group's ELISA units, the sensitivity of the IgG, IgA and IgM assays were 34%, 19% and 3% respectively; combining results of the IgG and IgA assays led to 43% positivity in children with active TB. CONCLUSION: The detection of anti 16-kDa IgG and IgA may be useful as a complementary technique for the diagnosis of childhood TB. Recognition of this antigen seems to be heterogeneous; combining responses against other antigens may be a good strategy to improve the performance of this assay.

Novel TSHR germline mutation (Met463Val) masquerading as Graves' disease in a large Welsh kindred with hyperthyroidism.

Hereditary nonautoimmune hyperthyroidism is caused by activating germline mutations in the thyrotropin (TSH) receptor (TSHR) gene. We describe an extended Welsh kindred with toxic thyroid hyperplasia affecting 8 family members in three generations and a history consistent with thyrotoxicosis in a further three generations now deceased. A novel heterozygous germline mutation (ATG --> GTG; Met463Val) was identified in the second membrane spanning TSHR region in 6 relatives with thyrotoxicosis and goiter and absence of TSHR antibodies. Screening of 5 additional family members led to the identification of 2 siblings with the mutation, who were asymptomatic at the time, although subsequent thyroid function tests in these children showed suppressed serum TSH and increased serum free triiodothyronine (FT3) and free thyroxine (FT4) concentrations. Functional studies of the novel TSHR germline mutation demonstrated a constitutive activation of the cAMP pathway, which in the thyroid controls both thyroid hormone production and stimulation of thyroid growth. The molecular diagnosis in this family has clinical implications: genetic counseling is required, and primary thyroid ablation should be advocated as the preferred treatment in the patients with the constitutively activating TSHR germline mutation.

Thyroid transcription factor-2 gene expression in benign and malignant thyroid lesions.

Thyroid transcription factor-2 (TTF-2) is a recently cloned thyroid-specific gene and is central to the development and differentiation of the thyroid follicular cell. Information regarding transcript levels in normal and diseased adult human thyroids is lacking. We have investigated TTF-2 gene expression in various thyroid pathologies and assessed its potential in preoperative diagnosis of thyroid nodular disease, which is a common clinical problem. We have used reverse transcription-polymerase chain reaction (RT-PCR) and in situ hybridization (ISH) and detected TTF-2 transcripts in 60% of 125 samples of adult human thyroids tested by RT-PCR (64% of 35) or ISH (59% of 90). In normal thyroid tissues TTF-2 transcript levels are low, 18 of 36 were weakly positive and 18 of 36 negative when tested by ISH. In the benign lesions, TTF-2 transcripts were detected either by RT-PCR or ISH in 8 of 8 Graves disease; 3 of 7 Hashimoto's; 2 of 2 follicular hyperplasia; 15 of 21 follicular adenoma; 11 of 13 multinodular goiters and 0 of 1 hyalinizing trabecular adenoma. In the malignant thyroid lesions, TTF-2 transcripts were detected in 8 of 18 follicular cancers; 0 of 2 anaplastic carcinoma, and 11 of 17 papillary cancers. Compared with normal thyroids, transcripts were more abundant in 24% of thyroid lesions tested by ISH. In conclusion, we report for the first time on TTF-2 gene expression in normal and diseased adult human thyroids.

Development and validation of an ELISA for the detection of leptospire-specific antibodies in rodents.

An enzyme-linked immunosorbent assay (ELISA) for the detection of IgG antibodies in rodents was developed and validated with the microscopic agglutination test (MAT) and leptospiral cultures. Sonicated antigen from cultures of serovars tarassovi and pyrogenes was used. As conjugate, a combination of anti-rat and anti-hamster IgG labeled with peroxidase was used. The optimal cut-off point was determined by plotting the sensitivity and specificity for various cut-off point values by means of receiver operating characteristic (ROC) curve. Concordance between ELISA and each of the MAT titers was measured by kappa (kappa). Proportions of positive results were compared by means of McNemar's test. Total 214 rodents were trapped, but only 117 could be processed by the three techniques (culture, ELISA, MAT; 1:20, 1:40, 1:50) and used for statistical analysis. Although, MAT titers in rodents infected with the serogroup Ballum tended to be lower than those infected with the serogroup Icterohaemorrhagiae, all (20/20) were ELISA-positive and almost all (19/20) were MAT-positive.The percentage of positive results obtained by ELISA, 47.0% exceeded significantly the 40.2% obtained by MAT (1:50). Difference between ELISA and MAT (1:40) was not significant and no differences were observed between ELISA and MAT (1:20). Agreement, specificity, sensitivity and the consequent area under the ROC curve between ELISA and MAT were higher as MAT cut-off points were lowered, being optimal at 1:20. The fact that differences between ELISA and MAT were significant at 1:50, but not at 1:40 or 1:20, supports the suggestion that lower MAT titers should be considered positive in rodents. The ELISA developed to detect leptospire-specific antibodies had optimal sensitivity and specificity in relation to MAT and it is concluded that it may constitute a very useful indicator for epidemiological purposes of past or present leptospiral infection in rodents.

Dermatologic uses of interferons.

Interferons are members of the cytokine family, with diverse antiviral, antiproliferative, antifibrotic, and immunomodulatory activities. Over the past 10 years, interferon use in clinical dermatology has extended beyond its historical antiviral efficacy. In this article, FDA-approved indications and non-FDA-approved dermatologic uses of interferons are reviewed.

Field-portable flow-injection analysers for monitoring of air and water pollution.

There has been a rapid growth in the development of field-portable analytical instrumentation capable of in-situ and real-time feedback of data from remote sites. Advances have been made in applications for many technologies aided by developments in electronics, computing and telecommunications systems. This report presents a brief review of these developments and particularly of portable flow-injection systems applied in both the liquid and gas phase modes of operation with potentiometric sensors and gas sensors of the tin-oxide semiconductor types.