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1.
BACKGROUND/PURPOSE: Sensitive skin is a condition associated with reduced tolerance to environmental factors and/or the application of topical products, such as cosmetics. Its pathophysiology has not been fully elucidated and few data are available on its prevalence. The aim of this study was to investigate possible correlation between objective sensitivity and skin surface microrelief. METHODS: During an epidemiological survey conducted for a campaign promoted by International Society of Plastic Dermatology in Italy, 243 adult healthy subjects of both sexes with no evident dermatological disorder but positive to the lactic acid stinging test, were submitted to cyanoacrylate stratum corneum stripping from the volar forearm for the determination of the irregularity of the skin surface microrelief (irregularity skin index (ISI)). RESULTS: A significant correlation was found between intensity of symptoms in stingers and ISI (r(s)=-0.47; P<0.001). CONCLUSION: Sensitive skin is common in the healthy population. ISI can contribute towards the identification of subjects with sensitive skin and the development of more specific skin treatments for this prevalent condition. 相似文献
2.
Michele D. Mignogna Stefano Fedele Lucio Lo Russo Lorenzo Lo Muzio 《Journal of oral pathology & medicine》2003,32(4):200-205
BACKGROUND: The recurrent chronic orofacial swelling caused by orofacial granulomatosis (OFG) can cause significant cosmetic and functional problems but can be prevented if the disease is diagnosed early and promptly treated. Although the enlargement of the lips is described to be the most common presenting complaint, the clinical onset of OFG may be characterized by minor associated mucosal and neurological manifestations, making early diagnosis very difficult or, sometimes, merely presumable. PATIENTS AND METHODS: We retrospectively analyzed the clinical manifestations of 19 patients with OFG, who were examined at our institution between 1998 and 2002, in order to determine their initial manifestations and presenting symptoms. RESULTS: A total of 10 patients showed classical recurrent enlargement of the lips (six lower; four upper) as presenting symptom. In the other nine patients, OFG onset was characterized by transient unilateral facial nerve palsy (two cases), intraoral manifestations (two cases), recurrent swelling of the periorbital area (two cases), of the chin (one case), of the zygomatic area (one case), and of the cheeks (one case). CONCLUSION: Our data underlined that OFG onset could be frequently characterized by widely variable, multiform, and temporary clinical findings. Involvement of atypical sites of the orofacial region and presence of single minor manifestations may occur as presenting symptoms, often preceding the development of traditional clinical findings. 相似文献
3.
C W Scott D P Blowers P T Barth M M Lo A I Salama C B Caputo 《Journal of neuroscience research》1991,30(1):154-162
Three isoforms of human tau protein were compared for their abilities to induce microtubule assembly. The three isoforms, tau 3 (tau containing three microtubule-binding domains), tau 4 (tau containing four microtubule-binding domains) and tau 4L (tau containing four microtubule binding domains plus a 58-amino-acid insert near the N-terminus) were expressed in E. coli and purified using ammonium sulfate precipitation, ion exchange, and size exclusion chromatography. All three isoforms induced microtubule assembly at micromolar concentrations and showed similar critical concentrations for assembly of 0.4-0.45 microM. However, tau 4 induced microtubule formation at a rate five- to tenfold faster than either tau 3 or tau 4L. The rate of microtubule elongation seen with tau 4 was twofold greater than with tau 3 or tau 4L, suggesting that the faster rate of microtubule assembly seen with tau 4 was due, at least in part, to faster elongation. Tau 4 induced a greater number of microtubules to form at steady state than did tau 3 or tau 4L. The microtubules generated with each tau isoform had similar steady-state length distributions and were equally susceptible to cold-induced disassembly. These results indicate that the additional microtubule-binding domain in tau 4 enhances microtubule assembly, while the 58-amino-acid insert negates the stimulatory effect of the fourth microtubule-binding domain. 相似文献
4.
Cerebrovascular and metabolic perturbations in delayed heavy charged particle radiation injury 总被引:5,自引:0,他引:5
E H Lo K A Frankel R L Delapaz A Poljak K H Woodruff K M Brennan M H Phillips P E Valk G K Steinberg J I Fabrikant 《Brain research》1989,504(1):168-172
Focal heavy charged particle irradiation of the rabbit brain created defined lesions which were observable by nuclear magnetic resonance (NMR) and positron emission tomography (PET) imaging techniques. The lesions appeared approximately 9-11 months after left partial hemibrain irradiation with 30 Gy (230 MeV/u helium ions), and were restricted to the white matter tracts and deep perithalamic and thalamic regions. 82Rubidium PET and Gadolinium DTPA enhanced NMR imaging were used to detect blood-brain barrier perturbations. 18Fluordeoxyglucose PET studies demonstrated widespread decreases in cerebral glucose uptake in the cortex and thalamus of the irradiated hemisphere. NMR and PET imaging results correlated well with histological findings. Rabbits irradiated with 15 Gy did not demonstrate any abnormalities in the brain with sequential NMR scans through 14 months post-irradiation. 相似文献
5.
New thermo-responsive, pH-responsive, and biodegradable nanoparticles comprised of poly(D,L-lactide)-graft-poly(N-isopropyl acrylamide-co-methacrylic acid) (PLA-g-P(NIPAm-co-MAA)) were developed by grafting biodegradable poly(D,L-lactide) onto N-isopropyl acrylamide and methacrylic acid. A core-shell type nano-structure was formed with a hydrophilic outer shell and a hydrophobic inner core, which exhibited a phase transition temperature above 37 degrees C suitable for biomedical application. Upon heating above the phase transition temperature, PLA-g-P(NIPAm-co-MAA) nanoparticle showed a polarity increase of pyrene in either buffer solution or intra-hepato-carcinoma cells as determined by fluorescence measurement, indicating that the structure of nanoparticles caused leakages from outer shell copolymers aggregation and collapsed. The drug loading level of 5-fluorouracil (5-FU) encapsulated in the PLA-g-P(NIPAm-co-MAA) nanoparticles can be as high as 20%. The release of 5-FU from nanoparticles was strongly controlled by the pH in the aqueous solution. Based on these results, PLA-g-P(NIPAm-co-MAA) nanoparticles can be used as a drug carrier for intracellular delivery of anti-cancer drug. 相似文献
6.
A series of new 4-aryl-5-[omega-(4-aryl-1-piperazinyl)alkyl]-2(3H)- oxazolones was synthesized and tested for neuroleptic activity in mice and rats. Several compounds exhibited interesting neuroleptic activity with very low liability to the extrapyramidal side effects. In particular the activity of 4-(4-fluorophenyl)-5-[2-[4-(3,5-dichlorophenyl)-1- piperazinyl]ethyl]-2(3H)-oxazolone (14) was greater than that of butropipazone and fluanisone, while of the same order of that of chlorpromazine; however, the product showed a longer lasting activity and minor ability to produce catalepsy as compared with the reference drugs. 相似文献
7.
8.
9.
Intracranial actinomycosis in juvenile patients
Case report and review of the literature 总被引:1,自引:0,他引:1
F. Puzzilli Maurizio Salvati Andrea Ruggeri Antonino Raco Roberto Bristot Stefano Bastianello Pierpaolo Lunardi 《Child's nervous system》1998,14(9):463-466
A case of actinomycotic brain infection in a juvenile patient is described. Cases of actinomycosis affecting the head and
neck are rare, particularly in juvenile patients. In this case complete resolution of the infection was achieved by means
of surgical treatment and prolonged antibiotic therapy. The authors emphasize the importance of a combined approach for treatment
of this unusual brain infection and stress the difficulties involved in the diagnosis of this pathology.
Received: 3 November 1997 相似文献
10.
Expression of tau protein in non-neuronal cells can result in a redistribution of the microtubule cytoskeleton into thick bundles of tau-containing microtubules (Lewis et al.: Nature 342:498-505, 1989; Kanai et al.: J Cell Biol 109:1173-1184, 1989). We reconstituted microtubule bundles using purified tubulin and tau in order to study the assembly of these structures. Taxol-stabilized tubulin polymers were incubated with various concentrations of recombinant human tau and examined by electron microscopy. With increasing concentrations of tau 3 (tau isoform containing three microtubule binding domains) or tau 4 (isoform containing four microtubule binding domains) the microtubules changed orientation from a random distribution to loosely and tightly packed parallel arrays and then to thick cables. In contrast, tau 4L, the tau isoform containing four microtubule binding domains plus a 58-amino acid insert near the N-terminus, showed minimal bundling activity. tau 4-induced bundling could be inhibited by the addition of 0.5 M NaCl or 0.4 mM estramustine phosphate, conditions which are known to inhibit tau binding to microtubules. A tau construct that contained only the microtubule binding domains plus 19 amino acids to the C-terminus was fully capable of bundling microtubules. Phosphorylation of tau 3 with cAMP-dependent protein kinase had no effect on its ability to induce microtubule bundling. These results indicate that tau protein is directly capable of bundling microtubules in vitro, and suggests that different tau isoforms differ in their ability to bundle microtubule filaments. 相似文献