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Quantum dots (QDs) are colloidal semiconductor nanocrystals of a few nanometers in diameter, being their size and shape controlled during the synthesis. They are synthesized from atoms of group II-VI or III-V of the periodic table, such as cadmium telluride (CdTe) or cadmium selenium (CdSe) forming nanoparticles with fluorescent characteristics superior to current fluorophores. The excellent optical characteristics of quantum dots make them applied widely in the field of life sciences. Cellular uptake of QDs, location and translocation as well as any biological consequence, such as cytotoxicity, stimulated a lot of scientific research in this area. Several studies pointed to the cytotoxic effect against micoorganisms. In this mini-review, we overviewed the synthesis and optical properties of QDs, and its advantages and bioapplications in the studies about microorganisms such as protozoa, bacteria, fungi and virus.

We report a case of tarsal tunnel syndrome (TTS) with focal conduction block across the tarsal tunnel (TT). A 46-year-old woman had pain in the left foot, sensory loss on the plantar surface, and positive Tinel sign over the TT. TTS was confirmed by magnetic resonance imaging (MRI) scan and surgery. Motor nerve conduction studies showed focal conduction block across the TT. Conduction block has rarely been reported in TTS. In this case, conduction block provides evidence for focal demyelination as the primary pathological process in TTS.

The electrophysiological response to words during the 'N400' time window (approximately 300-500 ms post-onset) is affected by the context in which the word is presented, but whether this effect reflects the impact of context on access of the stored lexical information itself or, alternatively, post-access integration processes is still an open question with substantive theoretical consequences. One challenge for integration accounts is that contexts that seem to require different levels of integration for incoming words (i.e., sentence frames vs. prime words) have similar effects on the N400 component measured in ERP. In this study we compare the effects of these different context types directly, in a within-subject design using MEG, which provides a better opportunity for identifying topographical differences between electrophysiological components, due to the minimal spatial distortion of the MEG signal. We find a qualitatively similar contextual effect for both sentence frame and prime-word contexts, although the effect is smaller in magnitude for shorter word prime contexts. Additionally, we observe no difference in response amplitude between sentence endings that are explicitly incongruent and target words that are simply part of an unrelated pair. These results suggest that the N400 effect does not reflect semantic integration difficulty. Rather, the data are consistent with an account in which N400 reduction reflects facilitated access of lexical information.

Semiconductor quantum dots (QDs) are highly fluorescent nanocrystals markers that allow long photobleaching and do not destroy the parasites. In this paper, we used fluorescent core shell quantum dots to perform studies of live parasite-vector interaction processes without any observable effect on the vitality of parasites. These nanocrystals were synthesized in aqueous medium and physiological pH, which is very important for monitoring live cells activities, and conjugated with molecules such as lectins to label specific carbohydrates involved on the parasite-vector interaction. These QDs were successfully used for the study of in vitro and in vivo interaction of Trypanosoma cruzi and the triatomine Rhodnius prolixus. These QDs allowed us to acquire real time confocal images sequences of live T. cruzi-R. prolixus interactions for an extended period, causing no damage to the cells. By zooming to the region of interest, we have been able to acquire confocal images at the three to four frames per second rate. Our results show that QDs are physiological fluorescent markers capable to label living parasites and insect vector cells. QDs can be functionalized with lectins to specifically mark surface carbohydrates on perimicrovillar membrane of R. prolixus to follow, visualize, and understand interaction between vectors and its parasites in real-time.

True neurogenic thoracic outlet syndrome (TOS) is an uncommon disorder despite of be a frequent reason for referral to the EMG laboratories. We describe the second case in the literature of true TOS in a competitive swimmer with progressive weakness and severe atrophy of the left thenar eminence. EMG showed lower trunk plexopathy. X-ray and MRI of the cervical spine and brachial plexus were normal. Surgical exploration evidenced the lower trunk retracted and pulled by a fibrous band. It was excised and neurolysis of the plexus was done with gradual improvement of function. We discuss the possible pathophysiology of this association.

Objective: The nerve conduction findings in interdigital neuropathy of the foot (IDN; Morton's neuroma) have rarely been reported. We analyzed the nerve conduction data in 23 patients with suspected IDN studied between 1982 and 2002., Method: Diagnosis of IDN was made on the basis of clinical features. All patients underwent routine nerve conduction studies and a near-nerve needle sensory nerve conduction study of the interdigital nerves by Oh's method in the symptomatic foot., Results: Of the 23 patients, the diagnosis of definite IDN was made in 13 cases and of possible NDN in the others cases. Nineteen were females. Twenty two patients had only one nerve affected. One patient had two nerves affected. The III-IV interdigital nerve was affected in 17 cases and the II-III interdigital nerve in 7 cases. The near-nerve needle nerve conduction showed abnormality in the affected interdigital nerves in all definite IDN cases and confirmed the diagnosis of IDN in 10 cases by the abnormal dip phenomenon (a selective decrease of 50% or more in the sensory CNAP amplitude of the affected nerve compared with that of the preceding interdigital nerve). In 11 possible IDN cases, IDN was identified by the abnormal dip phenomenon., Conclusion: The near-nerve needle sensory nerve conduction of the interdigital nerves is a highly sensitive diagnostic test, and abnormal dip phenomenon is the most characteristic electrophysiological marker for the diagnosis of IDN.

This study aims at verifying whether Portuguese gender-inflected nouns and adjectives are represented as full forms as suggested by Spanish data (Dominguez, Cuetos, & Segui, 1999). A series of lexical decision experiments is reported. Grammatical gender, frequency dominance, and grammatical category are manipulated and cumulative frequency is controlled. The results do not provide support for a full form representation of gender-inflected words. They suggest that grammatical category, or the nature of the inflectional process involved (lexical or syntactic), affects the way words are represented and accessed. Shorter recognition latencies were obtained for nouns drawn from Feminine dominant gender-inflected pairs than from Masculine dominant pairs whereas a tendency in the opposite direction was observed in adjectives. The effect of frequency dominance appears, nevertheless, to be restricted to feminine nouns. The data are compatible with the view that masculine nouns and adjectives are represented as gender-unmarked forms. These results are discussed in relation to current dual-access models of word recognition and to the notion of "interpretability" of lexico-syntactic features, as put forward in the Minimalist Program of Generative Linguistics.

Objective: In rats the available techniques for evaluation of sensory nerve conduction are limited. We report a new method of sensory nerve conduction of the plantar nerve using needle electrodes as the recording electrodes behind the medial malleolus and ring electrodes as the stimulating electrodes around the three middle toes., Methods: We performed this sensory nerve conduction test in 25 rats during their growth over a 6 weeks' period and compared this method with the motor nerve conduction and H-reflex sensory nerve conduction of the tibial nerve in 10 rats, and with the motor and mixed nerve conductions of the tail nerve in 15 rats., Results: There was a highly or moderately significant correlation between the body weight and sensory nerve conduction velocity (NCV) of the plantar nerve, mixed NCV and motor NCV of the tail nerve, indicating a growth-related increase in the NCV. The growth-related increase in the NCV was not observed in the motor and H-reflex sensory nerve conductions of the tibial nerves., Conclusions: This test is simple and reliable and can be used for the sensory nerve conduction test in rats.