Polymerase chain reaction compared to other laboratory findings and to clinical evaluation in the diagnosis of cutaneous tuberculosis and atypical mycobacteria skin infection

Cutaneous tuberculosis has re-emerged in the last 15 years together with the higher incidence of pulmonary tuberculosis and multidrug resistance. The choice for a single diagnostic tool among the many available today is a challenge. Our objective was to compare polymerase chain reaction (PCR) with other exams in the diagnosis of cutaneous tuberculosis and atypical mycobacteria skin infection. PCR and a set of five different exams were performed in 32 patients (34 samples of paraffin-embedded tissue) evaluated for 3 years in a university hospital, considering the response to mycobacterial infection treatment as a positive case. PCR was the most sensitive (88%) and specific (83%) exam. Culture, immunohistochemistry and acid-fast bacilli were not in agreement with clinical response to treatment. Although PCR is a useful tool, careful clinical exam is still the gold standard for the evaluation and treatment of cutaneous tuberculosis and mycobacteria skin infection.

Reliability of electromyographic amplitude values of the upper limb muscles during closed kinetic chain exercises with stable and unstable surfaces

The purpose of the present study was to evaluate the intra and interday reliability of surface electromyographic amplitude values of the scapular girdle muscles and upper limbs during 3 isometric closed kinetic chain exercises, involving upper limbs with the fixed distal segment extremity on stable base of support and on a Swiss ball (relatively unstable). Twenty healthy adults performed the exercises push-up, bench-press and wall-press with different effort levels (80% and 100% maximal load). Subjects performed three maximal voluntary contractions (MVC) in muscular testing position of each muscle to obtain a reference value for root mean square (RMS) normalization. Individuals were instructed to randomly perform three isometric contraction series, in which each exercise lasted 6 s with a 2-min resting-period between series and exercises. Intra and interday reliabilities were calculated through the intraclass correlation coefficient (ICC 2.1), standard error of the measurement (SEM). Results indicated an excellent intraday reliability of electromyographic amplitude values (ICC >= 0.75). The interday reliability of normalized RMS values ranged between good and excellent (ICC 0.52-0.98). Finally, it is suggested that the reliability of normalized electromyographic amplitude values of the analyzed muscles present better values during exercises on a stable surface. However, load levels used during the exercises do not seem to have any influence on variability levels, possibly because the loads were quite similar. (C) 2007 Elsevier Ltd. All rights reserved.

Bovine Bone Screws: Metrology and Effects of Chemical Processing and Ethylene Oxide Sterilization on Bone Surface and Mechanical Properties

We assess the effects of chemical processing, ethylene oxide sterilization, and threading on bone surface and mechanical properties of bovine undecalcified bone screws. In addition, we evaluate the possibility of manufacturing bone screws with predefined dimensions. Scanning electronic microscopic images show that chemical processing and ethylene oxide treatment causes collagen fiber amalgamation on the bone surface. Processed screws hold higher ultimate loads under bending and torsion than the in natura bone group, with no change in pull-out strength between groups. Threading significantly reduces deformation and bone strength under torsion. Metrological data demonstrate the possibility of manufacturing bone screws with standardized dimensions.

Angiotensin processing is partially carried out by carboxypeptidases in the rat mesenteric arterial bed perfusate

Here we investigated the possible association between the carboxypeptidase A (CPA)-like activity of the rat mesenteric arterial bed (MAB) perfusate and the ability of this fluid of forming angiotensin (Ang) 1-9 and Ang 1-7 upon incubation with Ang I and Ang II, respectively. Initially, we observed that anion exchange chromatography of the perfusate would consistently split the characteristic Z-Val-Phe-hydrolyzing activity of CPA-like enzymes into five distinct peaks, whose proteolytic activities were then determined using also Ang I and Ang II as substrates. The resulting proteolytic profile for each peak indicated that rat MAB perfusate contains a complex mixture of carboxypeptidases; tentatively, five carboxypeptidases were distinguished based on their substrate preferences toward Z-Val-Phe. Ang I and Ang II. The respective reactions, namely, Z-Val-Phe cleavage, Ang I to Ang 1-9 conversion and Ang II to Ang 1-7 conversion, were inhibited by 1,10-phenanthroline and nearly fully blocked by potato carboxypeptidase inhibitor. Also, all the CPA-like activity peaks prepared by anion exchange chromatography were tested negative for contaminating Ang I-converting enzyme-2, cathepsin A and prolylcarboxypeptidase. Overall, our results indicate that rat MAB perfusate contains a multiplicity of Ang I and Ang II-processing CPA-like enzymes whose proteolytic specificities suggest they might perform peculiar regulatory roles in the local resin-angiotensin system. (C) 2008 Elsevier B.V. All rights reserved.

NOVEL 65 kDa RNA-BINDING PROTEIN IN SQUID PRESYNAPTIC TERMINALS

A polyclonal antibody (C4), raised against the head domain of chicken myosin Va, reacted strongly towards a 65 kDa polypeptide (p65) on Western blots of extracts from squid optic lobes but did not recognize the heavy chain of squid myosin V. This peptide was not recognized by other myosin Va antibodies, nor by an antibody specific for squid myosin V. In an attempt to identify it, p65 was purified from optic lobes of Loligo plei by cationic exchange and reverse phase chromatography. Several peptide sequences were obtained by mass spectroscopy from p65 cut from sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) gels. BLAST analysis and partial matching with expressed sequence tags (ESTs) from a Loligo pealei data bank indicated that p65 contains consensus signatures for the heterogeneous nuclear ribonucleoprotein (hnRNP) A/B family of RNA-binding proteins. Centrifugation of post mitochondrial extracts from optic lobes on sucrose gradients after treatment with RNase gave biochemical evidence that p65 associates with cytoplasmic RNP complexes in an RNA-dependent manner. Immunohistochemistry and immunofluorescence studies using the C4 antibody showed partial co-labeling with an antibody against squid synaptotagmin in bands within the outer plexiform layer of the optic lobes and at the presynaptic zone of the stellate ganglion. Also, punctate labeling by the C4 antibody was observed within isolated optic lobe synaptosomes. The data indicate that p65 is a novel RNA-binding protein located to the presynaptic terminal within squid neurons and may have a role in synaptic localization of RNA and its translation or processing. (C) 2010 IBRO. Published by Elsevier Ltd. All rights reserved.

Haemophilus ducreyi detection by polymerase chain reaction in oesophageal lesions of HIV patients

HIV patients frequently have opportunistic oesophageal infections. We report Haemophilus ducreyi genetic material detected by polymerase chain reaction in biopsies of oesophageal lesions in three HIV-1-infected patients. This finding may be an indication of its aetiopathological role in oesophageal lesions of HIV patients.

THE INFLUENCE OF VIBRISSAL SOMATOSENSORY PROCESSING IN RAT SUPERIOR COLLICULUS ON PREY CAPTURE

The lateral part of intermediate layer of superior colliculus (SCI) is a critical substrate for successful predation by rats. Hunting-evoked expression of the activity marker Fos is concentrated in SCI while prey capture in rats with NMDA lesions in SCI is impaired. Particularly affected are rapid orienting and stereotyped sequences of actions associated with predation of fast moving prey. Such deficits are consistent with the view that the deep layers of SC are important for sensory guidance of movement. Although much of the relevant evidence involves visual control of movement, less is known about movement guidance by somatosensory input from vibrissae. Indeed, our impression is that prey contact with whiskers is a likely stimulus to trigger predation. Moreover, SCI receives whisker and orofacial somatosensory information directly from trigeminal complex, and indirectly from zona incerta, parvicelular reticular formation and somatosensory barrel cortex. To better understand sensory guidance of predation by vibrissal information we investigated prey capture by rats after whisker removal and the role of superior colliculus (SC) by comparing Fos expression after hunting with and without whiskers. Rats were allowed to hunt cockroaches, after which their whiskers were removed. Two days later they were allowed to hunt cockroaches again. Without whiskers the rats were less able to retain the cockroaches after capture and less able to pursue them in the event of the cockroach escaping. The predatory behaviour of rats with re-grown whiskers returned to normal. In parallel, Fos expression in SCI induced by predation was significantly reduced in whiskerless animals. We conclude that whiskers contribute to the efficiency of rat prey capture and that the loss of vibrissal input to SCI, as reflected by reduced Fos expression, could play a critical role in predatory deficits of whiskerless rats. (C) 2011 IBRO. Published by Elsevier Ltd. All rights reserved.

Inhibitory network interactions shape the auditory processing of natural communication signals in the songbird auditory forebrain

The role of GABA in the central processing of complex auditory signals is not fully understood. We have studied the involvement of GABA(A)-mediated inhibition in the processing of birdsong, a learned vocal communication signal requiring intact hearing for its development and maintenance. We focused on caudomedial nidopallium (NCM), an area analogous to parts of the mammalian auditory cortex with selective responses to birdsong. We present evidence that GABA(A)-mediated inhibition plays a pronounced role in NCM`s auditory processing of birdsong. Using immunocytochemistry, we show that approximately half of NCM`s neurons are GABAergic. Whole cell patch-clamp recordings in a slice preparation demonstrate that, at rest, spontaneously active GABAergic synapses inhibit excitatory inputs onto NCM neurons via GABA(A) receptors. Multi-electrode electrophysiological recordings in awake birds show that local blockade of GABA(A)-mediated inhibition in NCM markedly affects the temporal pattern of song-evoked responses in NCM without modifications in frequency tuning. Surprisingly, this blockade increases the phasic and largely suppresses the tonic response component, reflecting dynamic relationships of inhibitory networks that could include disinhibition. Thus processing of learned natural communication sounds in songbirds, and possibly other vocal learners, may depend on complex interactions of inhibitory networks.

In vitro susceptibility to antimycotic drug undecanoic acid, a medium-chain fatty acid, is nutrient-dependent in the dermatophyte Trichophyton rubrum

The antimycotic activity of fatty acids has long been known, and their presence in human skin and sweat appears to protect the host against superficial mycoses. Undecanoic acid is a medium-chain fatty acid that has been used in the treatment of dermatophytoses in humans. In this study, we selected one Trichophyton rubrum undecanoic acid-resistant strain that showed a marked reduction in its capacity to grow on human nail fragments, which correlated with the reduced activity of secreted keratinolytic proteases. Moreover, the susceptibility of T. rubrum to undecanoic acid is also dependent on the carbon source utilized by both control and resistant strains. The growth of the control strain was strongly inhibited by undecanoic acid in Sabouraud medium or in cultures supplemented with low-fat milk, whereas it was ineffective when the cultures were supplemented with Tween 20 or keratin as the carbon source, suggesting that nutrient conditions are crucial in establishing a susceptibility to antifungal drugs, which is helpful for the isolation and characterization of resistant strains, and in the screening for new antifungal drugs.