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61.

Introduction

Parry-Romberg syndrome is a rare entity of unknown etiology, characterized by hemifacial or hemibody atrophy affecting subcutaneous tissues. Its main clinical manifestations are neurological, ocular and dermatological. Paroxysmal kinesigenic dyskinesia (PKD) is characterized by brief episodes of choreic/dystonic movements triggered by sudden movements and improved by antiepileptic drugs particularly carbamazepine. It can be sporadic or familial with an autosomal dominant inheritance. Little is known about the pathophysiology of PKD, although a channelopathy is thought likely. The association of these two diseases is rare.

Case report

Over three years, a 42-year-old patient progressively developed left hemiatrophy. Since age 14, he presented paroxysmal dystonic disorders of the limbs triggered by sudden movements and controlled by carbamazepine. The diagnosis of PKD associated with Parry-Romberg syndrome was established. Investigations revealed immunologic and diffuse electrophysiological abnormalities (EEG and EMG).

Conclusion

PKD associated with Parry-Romberg syndrome is very rare but does not appear to be fortuitous. It suggests a common mechanism via an underlying channelopathy or dysimmune disorder.  相似文献   
62.
Social insects like ants exhibit sophisticated communication by means of pheromones, one example of which is the use of alarm pheromones to alert nestmates for colony defense. In the ant Camponotus obscuripes, we have reported that information about formic acid and n-undecane, alarm pheromone components, is processed in a set of specific glomeruli in the antennal lobe (primary olfactory center). Alarm pheromone signals are then transmitted, mainly via uniglomerular projection neurons (uni-PNs), to the protocerebrum (PR), where sensory signals are integrated to form motor commands for behavioral responses. In this study, we physiologically and morphologically characterized 63 alarm pheromone-sensitive PR neurons in ants by using intracellular recording and staining techniques. Most of the pheromone-sensitive PR neurons had dendrites in the mushroom body (MB), the lateral horn, or the medial PR. Some neurons with dendrites in these areas responded specifically to formic acid or n-undecane and may participate in the control of specific behavioral responses to each pheromone component. Other neurons responded also to non-pheromonal odors, in contrast to uni-PNs, most of which responded specifically to alarm pheromones. Responses to non-pheromonal odors were most prominent in efferent neurons of the MB lobe, suggesting that they may participate in integration of pheromonal and non-pheromonal information. We found a class of PR neurons that receives input in all of these pheromone-processing areas and terminates in a variety of premotor areas. These neurons may participate in the control of pheromone-sensitized aggressive behavior, which is triggered by non-pheromonal sensory stimuli associated with a potential enemy.  相似文献   
63.
Capsicum peppers are widespread both in and out the kitchen. "Human hand" is a contact dermatitis resulting from the direct handling of peppers. Capsaicin also is found in topical agents for treatment of postherpetic neuralgia, diabetic neuropathy and arthritis. The oleoresin of capsicum is considered a powerfull irritant capable to induce irritant contact dermatitis and non‐immunological contact urticaria. A 81 year‐old man with a severe itchy macular and papular rash induced by Capsidol® initially located over the shoulder and sudden spread over the thorax is presented. A dense dermal mononuclear cell infiltrate and spongiosis suggested the diagnosis of contact dermatitis. Negative open tests and a positive patch test reaction (++ 96 hours) using the trade cream Capsidol®(capsaicin 5%) led us to contact with the Pharmaceutical Company Viñas. They provided us the components of the cream: capsaicin, isopropyl myristate, estearic acid (DERVACID 3148), propylene glycol, glycerin monomyristate (ESTOL3650GMM), AMPHISOL K, Cetyl alcohol (NACOL 16–85), benzyl alcohol, diazolidinyl urea (GERMALL II), p‐hydroxybenzoate–methylsodium (NIPAGIN M sódic), p‐hydroxybenzoate propyl (NIPASOL M). Capsaicin in benzyl alcohol at 0,075% was open tested with negative results. Only patch test with capsaicin was positive (++) at 48/96 hours and the excipient components at the appropiate concentrations were all negative. Patch test biopsy showed an eczematous pattern. Twenty controls showed negative results. This case is probably an allergic reaction but shows how still remains difficult to distinguish among allergic and irritative cutaneous reactions.  相似文献   
64.
Nowadays, caterpillars are included among the agents that elicit contact urticaria by a non‐immunologic mechanism. Our objective was to find the rôle that an IgE‐mediated mechanism could have among patients with suspected contact urticaria from pine processionary caterpillars. 16 patients with suspected contact urticaria from this caterpillar were studied by prick testing and specific IgE detection by immunoblotting. 87% of the patients had a positive prick test and immunoblotting for caterpillar extract. In these allergic patients, the symptoms associated with urticaria were: angioedema (79%), conjunctivitis (36%) and severe anaphylaxis (14%). The most frequent localizations of the wheals were the neck (100%) and forearms (93%). Angioedema was more frequent on the eyelids (79%). The IgE‐immunoblot detected in the caterpillar extract several reactive bands, with apparent MWs from to 45 to 4kDa. A total of 5 major allergens were identified, but a band around 14kDa proved to be the dominant allergen. Sensitization to Thaumetopoea pityocampa was found to be the most important mechanism of airborne contact urticaria from this caterpillar. Low‐MW proteins are the main IgE binding components of crude caterpillar extract.  相似文献   
65.
66.
Man has used hallucinogenic plants and mushrooms for centuries. The characteristics of these plants that led to their incorporation into important ritualistic and spiritual traditions, however, have also resulted in their widespread propagation and abuse. Hallucinogenic plants have long been depicted as innocuous substances, yet their unpredictable nature makes intoxication potentially dangerous. In present‐day society, there is greater access to these drugs and a growing trend among the younger generations to experiment with these plants in a recreational fashion. Emergency physicians need to be aware of the potential sources of plant hallucinogens and the spectrum of toxic effects. A review of the more common hallucinogenic plants and fungi is discussed with reference to historical, pharmacological and clinical aspects of these intoxications.  相似文献   
67.
Selection of appropriate oviposition sites is essential for progeny survival and fitness in generalist insect species, such as Drosphila melanogaster, yet little is known about the mechanisms regulating how environmental conditions and innate adult preferences are evaluated and balanced to yield the final substrate choice for egg-deposition. Female D. melanogaster are attracted to food containing acetic acid (AA) as an oviposition substrate. However, our observations reveal that this egg-laying preference is a complex process, as it directly opposes an otherwise strong, default behavior of positional avoidance for the same food. We show that 2 distinct sensory modalities detect AA. Attraction to AA-containing food for the purpose of egg-laying relies on the gustatory system, while positional repulsion depends primarily on the olfactory system. Similarly, distinct central brain regions are involved in AA attraction and repulsion. Given this unique situation, in which a single environmental stimulus yields 2 opposing behavioral outputs, we propose that the interaction of egg-laying attraction and positional aversion for AA provides a powerful model for studying how organisms balance competing behavioral drives and integrate signals involved in choice-like processes.  相似文献   
68.
69.
Allergy to pine nuts   总被引:1,自引:0,他引:1  
D. de las  Marinas  L. Vila    M. L. Sanz 《Allergy》1998,53(2):220-222
  相似文献   
70.
Medicinal mushrooms occurring in South India namely Ganoderma lucidum, Phellinus rimosus, Pleurotus florida and Pleurotus pulmonaris possessed profound antioxidant and antitumor activities. This indicated that these mushrooms would be valuable sources of antioxidant and antitumor compounds. Investigations also revealed that they had significant antimutagenic and anticarcinogenic activities. Thus, Indian medicinal mushrooms are potential sources of antioxidant and anticancer compounds. However, intensive and extensive investigations are needed to exploit their valuable therapeutic use.  相似文献   
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