Preliminary assessment of Treponema pallidum-specific IgM antibody detection and a new rapid point-of-care assay for the diagnosis of syphilis in human immunodeficiency virus-1-infected patients

The aims of the study were to assess whether Treponema pallidum-specific IgM may provide a useful marker of infectious syphilis in human immunodeficiency virus (HIV)-infected patients, and to compare the performance of a prototype IgM-rapid point-of-care test (PoCT) with a standard IgM-enzyme immunoassay (EIA). Twenty samples from HIV-infected patients with untreated syphilis (n = 4 primary syphilis, n = 11 secondary and n = 5 early latent) and 51 follow-up samples at three, six or 12 months after treatment were tested for the presence of IgM with the Mercia-EIA (Microgen Bioproducts Ltd, Camberley, UK) and a prototype PoCT (Select Vaccines Ltd, Melbourne, Australia). Although sample numbers were small, IgM detection by EIA appears to be a reliable marker for untreated syphilis in HIV-infected patients with primary (4/4 IgM-positive) or secondary syphilis (10/11 IgM-positive, 1/11 equivocal). After treatment, IgM was no longer detected after three months in the majority of patients (87%) and was either negative or equivocal in all patients after six and 12 months. The overall sensitivity of the IgM-PoCT was 82% and varied with clinical stage, being highest in secondary (10/10 EIA positives) but lower in primary (2/4 EIA positives) and early latent syphilis (2/3 EIA positives). Overall specificity was 95%. Rapid detection of IgM would enable clinicians to distinguish between past-treated and infectious syphilis and allow for diagnosis and treatment in a single visit.

Calculation of Young's modulus value by means of AFM

In the last years, Atomic Force Microscopy (AFM) has become a powerful tool not only to study the surface morphology but also the nanomechanics of all kind of samples. In this paper, the applicability of this technique is reviewed and its basic aspects of operation, advantages and drawbacks of using the AFM probe as a picoindenter (Force Spectroscopy mode, FS-AFM) are discussed. The patents concerning picoindentation measurements are discussed in the text and special attention is paid to measurements performed on hard materials as ceramics, as they have not been as thoroughly reviewed in the literature as in the case of soft matter. The possibilities of AFM in the nanomechanics field include the quantitative determination of the Young's modulus (E) and the transition force from elastic to plastic deformation regimes, the measurement of adhesion forces and deformation mechanisms while applying vertical forces in the range from tens of pN to μN.

Incidence and prevalence of psoriatic arthritis in Buenos Aires, Argentina: a 6-year health management organization-based study

OBJECTIVES

Studies regarding epidemiology of PsA are lacking in Latin America. We estimated the incidence and prevalence of PsA in a University Hospital-based Health Management Organization in Buenos Aires [Hospital Italiano Medical Care Program (HIMCP)].

METHODS

POPULATION

for incidence calculation, the population at risk was all adult members of the HIMCP, with continuous affiliation for at least 1 year from January 2000 to January 2006. Each person was followed until he/she voluntarily left the HIMCP, death or finalization of the study (final dates) contributing time at risk since January 2000 or enrolment date (whichever occurred later) to that final date. Case ascertainment: medical records of all patients with the problem psoriasis and/or PsA in the HIMCP problem-oriented computer-based patient record system, or registered in rheumatologists and/or dermatologists databases, were revised. Patients fulfilling CASPAR criteria were included.

STATISTICAL ANALYSIS

incidence rate (IR) was calculated with 95% CIs. Cumulative prevalence was estimated on 1 January 2006 (denominator population ==88,112).

RESULTS

In the study period, 138,288 persons contributed a total of 558,878 person-years, of whom 35 developed PsA (IR 6.26; 95% CI 4.2, 8.3 cases per 100,000 person-years). There were 12 females: IR 3.64 (95% CI 1.6, 5.7) cases per 100,000 person-years; and 23 males: IR 10.02 (95% CI 5.9, 14.1) cases per 100,000 person-years. On 1 January 2006, 65 prevalent cases were identified: prevalence 74 (95% CI 57, 94) cases per 100,000 members.

CONCLUSIONS

The incidence and prevalence of PsA in this Latin American country was similar to that reported in other studies from Europe and the USA.

Stem Rot of Branched Broomrape (Orobanche ramosa) Caused by Sclerotium rolfsii in Chile

Branched broomrape is a holoparasitic weed present in some areas of central and southern Chile (33°S to 38°S), which is often found parasitizing tomato and tobacco crops. During an extensive survey conducted in different tomato-growing areas during the summer of 2010, branched broomrape plants with stem rot symptoms were detected in a commercial tomato crop located in the central zone (34°14'S, 71°1'W). Rotten stems were observed with white mycelia and approximately 1-mm-diameter spherical sclerotia on affected tissue below the soil surface. Parasitized tomato plants showed no symptoms. Sclerotia were taken directly from affected stems with a dissecting needle under a stereoscopic microscope in a flow chamber and placed on potato dextrose agar (PDA) medium. Germinating sclerotia consistently produced colonies similar to Sclerotium rolfsii with new sclerotia formed within 6 to 7 days. Mycelia produced hyphal clamp connections under the light microscope (2). DNA was extracted from one fungal culture. The ITS1 region, 5.8S rRNA gene, and the ITS2 region of the nuclear-encoded ribosomal RNA gene were amplified with primers ITS1 and ITS4 (4). The sequence was deposited in GenBank (Accession No. HM222638) and showed ≥99% identity values with sequences of similar regions from Athelia rolfsii (anamorph S. rolfsii; Accession Nos. AB075304, DQ0595578, AF499018, and AB075305). Different pathogenicity tests were performed. Inoculum was prepared by placing mycelia plugs from a PDA-grown, 6-day-old colony in a flask with sterilized wheat seeds and incubated for 2 weeks. Three Orobanche plants, each one with 10 to 15 shoots at different aerial stages (starting emergence, flowering, and formed capsules) were gently planted separately in 35-cm pots. Inoculum (10 g per pot) was placed in the soil surrounding the plants. One pot was used as a control. Forty-five-day-old tomato and tobacco plants were additionally inoculated by a similar procedure. After 12 days, inoculated Orobanche plants showed reduced vigor and stem decay. After 9 days, tomato and tobacco plants showed wilt. In all cases, the fungus was reisolated on PDA from all inoculated plants. To our knowledge, this is the first report of S. rolfsii on O. ramosa (1). A previous report of S. rolfsii parasitizing O. cernua has also been made (3). The high susceptibility of tomato and tobacco plants to this isolate of S. rolfsii precludes the use of this pathogen as a biological control agent against broomrape. References: (1) D. F. Farr and A. Y. Rossman. Fungal Databases. Systematic Mycology and Microbiology Laboratory, ARS, USDA. Retrieved May 14, 2010, from http://nt.ars-grin.gov/fungaldatabases . (2) Z. K. Punja and A. Damiani. Mycologia 88:694, 1996. (3) C. A. Raju et al. Phytoparasitica 23:235, 1995. (4) T. J. White et al. Amplification and direct sequencing of fungal ribosomal RNA genes for phylogenetics. Page 315 in: PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, New York, 1990.

Illicit drug use in seven Latin American countries: critical perspectives of families and familiars

This cross-sectional multi-centre study explored how family members and friends of illicit drug users perceived protective and risk factors, treatment facilities and policies and laws regarding illicit drug use. Family members and friends of illicit drug users were recruited in 10 urban health care outpatient units in 7 Latin American countries (Brazil, Colombia, Costa Rica, Ecuador, Guatemala, Honduras and Mexico) to complete a questionnaire. The majority of the respondents chose psycho-social factors over genetic or biological explanations as causes of drug problems. Respondents felt that families and governments were responsible for preventing drug problems. Church/religious institutions were most often mentioned in the context of accessible treatment. When asked about access to treatment facilities, the majority said that there were not enough. Shame about drug use, cost, and limited treatment options were most often cited as barriers to treatment.

In Silico Analysis of Breast Cancer Transcriptome Libraries Distinguish Tumor Subclasses

BackgroundBreast carcinoma is one of the most common causes of cancer related death worldwide. However marked differences in outcomes may reflect variation in diagnostic, staging and treatment. Serial Analysis of Gene Expression (SAGE) is a comprehensive profiling method that allows for global, unbiased and quantitative characterization of transcriptomes. A major advantage of SAGE is that once normalized it is possible to directly compare the levels of tags (short nucleotide sequences) generated by a single experiment with any other compatible available.MethodsTo gain an insight on the relationship between breast cancer transcriptomes and the disparate outcomes observed, we retrieve 18 SAGE libraries (4 Normal breast tissues, 11 primary breast tumors and 3 breast cancer metastatic tissues) from Cancer Genome Anatomy Project (CGAP). Data were analyzed by Correspondence Analysis (COA), Hierarchical clustering, Support Tree (ST) and Significance Analysis for Microarray (SAM) using TMEV software (tm4.org). Tags assignment to genes was performed by CGAP, and pathways analysis by FatiGO (babelomics.bioinfo.cipf.es).ResultsThe selection process to find SAGE tags that were consistently expressed in all normal, tumor and metastatic libraries resulted in 2,437 tags. COA shows clear separation between normal and metastatic libraries. These results were confirmed by Support Tree using the Pearson Correlation and Average Linkage (Fig 1). Interestingly, the 11 tumor SAGE libraries consisted of two heterogeneous groups, one similar to metastatic libraries (cases 1, 2, 8, 9, 10, 11) and the other to normal libraries (cases 3, 4, 5, 6, 12). Next, to identify SAGE tags differentially expressed between these two different groups of tumors, we performed SAM (delta value = 1.38, fold discovery rate = 0, 1001 unique permutations and fold change = 10). This approach revealed 59 (6%) tags differentially expressed across both tumor libraries. Among these 59 tags, 3 were up-regulated in tumors associated to normal libraries (normal-like tumors) and 56 were up-regulated in tumors associated to metastatic libraries (metastatic-like tumors). Next, tag to gene association identified 48 genes. Pathway analysis of these 48 genes revealed that tumors similar to normal libraries were characterized by activation of apoptosis and protein kinase pathways (JUND, GADD45B) and tumors similar to metastatic libraries were associated with response to extracellular stimulus, cell surface receptor linked signal transduction, Wnt receptor signaling pathway, cell cycle, phosphorylation, mRNA metabolic process, cell proliferation, regulation of cell proliferation, DNA replication, peptide metabolic process, signal peptide processing (NDUFB2, RPS27A, COX6B1, RBBP4, NDUFB9). These pathways may be implicated in outcomes to drug therapies.ConclusionsComprehensive analysis 2,437 tags from whole transcriptomes of primary breast cancer tissue compared with normal breast tissue and breast cancer metastatic tissues revealed that clinically disparate outcomes could be linked to a relatively small number of transcripts, since 6% (59 tags) were responsible of the differences across the normal-like and the tumor-like breast tumors.Supported FONDECYT 1080563 – Government of Chile

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 1165.

Use of frequency analysis on the ECG for the prognosis of low energy cardioversion treatment of atrial fibrillation

Electric cardioversion is the most effective therapy for restoring sinus rhythm in patient with atrial fibrillation (AF), however, there is not a guiding criteria for advising on when and in whom it will be successful. The objective of this study was to employ frequency analysis on the surface electrocardiogram (ECG) to predict the outcome of low energy internal cardioversion in patients with AF. Thirty nine patients with AF, for elective DC cardioversion were included in this study. One catheter was positioned in the right atrial appendage and another in the coronary sinus. A voltage step-up protocol (50-300 V) was used for patient cardioversion. Prior to shock delivery, residual atrial activity signal (RAAS) was derived from 60 seconds of surface ECG from defibrillator pads, by bandpass filtering and ventricular activity (QRST) cancellation. Dominant atrial fibrillatory frequency (DAFF) was estimated from the RAAS power spectrum as the dominant frequency within the 3-12 Hz band. DAFF was calculated from whole 60 seconds segment (DAFF_L) and from the finals 10 seconds segment (DAFF_S) of the RAAS. Lower DAFF_L and DAFF_S were found in successfully cardioverted patients than in those nonsuccessful ones, with energy < or =3 and < or =6 joules. Therapy result (employing 3J or less) was predicted in 35/39 (89.7%) patients with DAFF_L=5.40Hz, and DAFF_L was > or =5.75Hz in a 100% of noncardioverted patients. In conclusion, frequency analysis of the RAAS could be useful for predicting success of low energy internal cardioversion of patients with atrial fibrillation.

Striatal GPR88 expression is confined to the whole projection neuron population and is regulated by dopaminergic and glutamatergic afferents

GPR88, an orphan G protein-coupled receptor, was designated Strg/GPR88 for striatum-specific G protein-coupled receptor (K. Mizushima et al. (2000)Genomics, 69, 314-321). In this study, we focused on striatal GPR88 protein localization using a polyclonal antibody. We established that the distribution of immunoreactivity in rat brain matched that of GPR88 transcripts and provided evidence for its exclusive neuronal expression. GPR88 protein is abundant throughout the striatum of rat and primate, with expression limited to the two subsets of striatal projection medium spiny neurons (MSNs) expressing preprotachykinin-substance P or preproenkephalin mRNAs. Ultrastructural immunolabelling revealed the GPR88 concentration at post-synaptic sites along the somatodendritic compartments of MSNs, with pronounced preference for dendrites and dendritic spines. The GPR88-rich expression, in both striatal output pathways, designates this receptor as a potential therapeutic target for diseases involving dysfunction of the basal ganglia, such as Parkinson's disease. Hence, we investigated changes of GPR88 expression in a model of Parkinson's disease (unilateral 6-hydroxydopamine-lesioned rats) following repeated L-DOPA treatment. In dopamine-depleted striatum, GPR88 expression was differentially regulated, i.e. decreased in striatopallidal and increased in striatonigral MSNs. L-DOPA treatment led to a normalization of GPR88 levels through dopamine D1 and D2 receptor-mediated mechanisms in striatopallidal and striatonigral MSNs, respectively. Moreover, the removal of corticostriatal inputs, by ibotenate infusion, downregulated GPR88 in striatopallidal MSNs. These findings provide the first evidence that GPR88 is confined to striatal MSNs and indicate that L-DOPA-mediated behavioural effects in hemiparkinsonian rats may involve normalization of striatal GPR88 levels probably through dopamine receptor-mediated mechanisms and modulations of corticostriatal pathway activity.

A correlative study of clinical and histological findings of revision hip arthroplasty for rheumatoid arthritis and inflammatory joint disease

OBJECTIVE

Primary hip arthroplasty in rheumatoid arthritis (RA) and other forms of inflammatory joint disease (IJD) is generally thought to be associated with a less favourable outcome in terms of implant survival and other complications. Whether the duration of implant survival correlates with the degree of rheumatoid-like inflammatory changes in periprosthetic tissues is uncertain.

METHODS

Histopathological changes in periprosthetic tissues obtained following revision surgery of 34 total hip replacements on 27 patients with IJD (RA 18 cases: ankylosing spondylitis three cases; juvenile chronic arthritis six cases) were examined.

RESULTS

A heavy diffuse lymphocyte and plasma cell infiltrate +/- lymphoid aggregates was noted in 29% of cases in whom the mean implant survival was 5.6 years (range: 2-8 years). Where little or no lymphocytic infiltrate was noted in periprosthetic tissues, the mean implant survival was 8.6 years (range: 1-17 years). Revision arthroplasty was not undertaken for early or late infection of a primary hip replacement.

CONCLUSIONS

Our findings indicate that implant survival is less in those cases where there is a heavy lymphocyte and plasma-cell infiltrate in periprosthetic tissues. These findings suggest that the presence of a heavy chronic inflammatory-cell infiltrate in periprosthetic tissues is likely to be a contributory factor in causing early implant failure in RA.

High-Density Transcranial Direct Current Stimulation (HD-tDCS): Hardware Interface

Transcranial Direct Current Stimulation (tDCS) is a non-invasive procedure where a weak electrical current (260 μA to 2 mA) is applied across the scalp to modulate brain function. tDCS has been applied for therapeutic purposes (e.g., addiction, depression, mood and sleep disorders) as well as cognitive performance enhancement (e.g., memory consolidation, motor learning, language recall). Despite safety and cost advantages, the developments of tDCS therapies have been restricted by spatial targeting concerns using existing two-channel systems. We have developed novel technology for High-Density tDCS (HD-tDCS) that improves spatial focality. Our hardware interface integrates a multichannel stimulating guide with existing two channel tDCS stimulators, and can be configured to target specific brain regions using computational models of current flow and multichannel array accessories. The hardware interface provides real time stimulation quality and safety feedback, and is designed to be MRI and TMS compatible. An electrical “tickle” feature enables skin pre-conditioning to minimize sensation. The full system includes the hardware interface, cable assemblies, head gear, tDCS electrodes, tDCS gel, and electrode adaptors. The head gear allows fixing the electrode adaptors over cortical targets using conventional EEG electrode coordinates. The electrode adaptors “fin” design, tDCS gel composition, and electrode shape are optimized to reduce sensation during direct current stimulation with 2 mA for up to 22 minutes. A five electrode system (4×1-C1), for implementing optimally focal “4×1 ring configuration” protocols, and an 8 electrode system (4×4-S1), that can be configured for “4×4 cortical strip stimulation”, are available. The entire system is robust, intuitive, and ultimately adaptable for home use. Our HD-tDCS system allows non-invasive, safe, and targeted modulation of selected cortical structures for electrotherapies that are individualized as well as optimized for a range of therapeutic applications.

High-Density Transcranial DC Stimulation (HD-tDCS): Targeting Software

Transcranial Direct Current Stimulation (tDCS) is a non-invasive procedure where a weak electrical current (260 μA to 2 mA) is applied across the scalp to modulate brain function. tDCS has been applied for therapeutic purposes (e.g., addiction, depression, mood and sleep disorders) as well as cognitive performance enhancement (e.g., memory consolidation, motor learning, language recall). Despite safety and cost advantages, the developments of tDCS therapies have been restricted by spatial targeting concerns using existing two-channel systems. We have developed novel technology for High-Density tDCS (HD-tDCS) that improves spatial focality. To determine optimal stimulation electrode configurations, based on application specific constraints, we developed a HD-tDCS targeting software. High resolution (gyri/sulci precise) MRI derived finite element (FE) human head models are generated by segmenting grey matter, white matter, CSF, skull, muscle, fatty tissue, eyes, blood vessels, scalp, etc. The models comprised >10 million elements with >15 million degrees of freedom. The induced cortical electric field/current density values are calculated; activation of either radially and tangentially oriented neuronal structures are considered. Our HD-tDCS hardware (4×1-C1, 4×4-S1) currently supports the ‘4×1-Ring’ and the ‘4×4-Strip’ electrode configurations. The peak cortical electric field was matched to ‘conventional’ large rectangular-pad tDCS stimulation; however, the spatial focality was significantly enhanced by 4×1 configuration. Using patient specific head models, our software interface allows simple and rapid screening of stimulation electrode configurations. After selecting a target region, clinicians can customize the electrode configuration to balance: 1) cortical surface and brain depth stimulation focality; 2) total applied current/voltage; and 3) electrode/scalp current density. Our HD-tDCS system allows non-invasive, safe, and targeted modulation of selected cortical structures for electrotherapies that are individualized as well as optimized for a range of therapeutic applications.

Sexual risk behaviours and HIV seroprevalence among male sex workers who have sex with men and non-sex workers in Campinas, Brazil

OBJECTIVES

To compare population-based prevalence estimates of sexual risk behaviours and HIV seroprevalence of male sex workers who have sex with men (MSM) and those not engaged in sex work in Campinas, Brazil.

METHODS

MSM (n = 658) were recruited for a cross-sectional study through respondent-driven sampling. Audio-assisted computer self-interview was used to collect information on sexual behaviours and HIV testing (optional) was performed. Population-based prevalence estimates with 95% CI of characteristics and behaviours of MSM sex workers and non-sex workers are reported.

RESULTS

One-quarter reported ever receiving payment for sex and 14.8% (95% CI 11.1 to 19.0) had been paid in the previous 2 months; most exclusively with men. MSM sex workers were significantly more likely than non-sex workers to report being transgendered (40.5% vs 8.1%), to practise unprotected receptive (22.4% vs 4.6%) and insertive (20.5% vs 5.0%) anal intercourse with > or =2 male partners and to have unprotected vaginal sex with women (22.7% vs 5.6%). MSM sex workers experienced significantly greater rates of psychological abuse (80.9% vs 58.4%) and physical abuse (48.2% vs 15.2%).

CONCLUSIONS

MSM sex workers have higher sexual risk behaviours as well as social vulnerabilities than the general population of MSM. HIV/sexually transmitted infection prevention efforts should be targeted to this riskier subgroup. Programmes should be transgender sensitive, should recognise that MSM sex workers have sex with men and women and address other factors that influence risk, such as homophobic abuse.