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61.
Giuliani C Bini LM Papa F Cristalli G Sagratini G Vittori S Lucarini D Maggi F 《化学与生物多样性》2011,8(12):2179-2194
Sideritis italica (Mill.) Greuter et Burdet belongs to the Lamiaceae family and is endemic to Italy. The glandular trichomes (morphology, distribution, histochemistry, and ultrastructure) of the plant were studied for the first time, along with the chemical composition of the essential oils. Abundant non-glandular hairs and peltate (type A) and capitate (types B, C(1), and C(x)) glandular trichomes were observed both on the vegetative and reproductive organs. The histochemical procedures and the ultrastructural investigation enabled specific location of the main site of essential oil production mainly in type-A peltate hairs. Particular emphasis is given to the release mechanism of the secreted material in all of the types of glands, and the potential taxonomic value of the indumentum in the Lamiaceae family is briefly discussed. Essential oils were hydrodistilled from flowering aerial parts of S. italica, and 136 compounds (112 in flowerheads, 79 in vegetative parts) were identified. The quantitative prevalence of diterpenoids (43.4% in flowerheads and 22.3% in vegetative parts) was the most significant characteristic of the essential oil of S. italica that could be classified as a diterpene-rich essential oil according to the classification of Kirimer. 相似文献
62.
The aim of this work was to trap the volatiles released from whole frozen and dry aerial parts, and, separately, from different organs (leaves, stems, corolla and calyx) of bastard balm (Melittis melissophyllum L., Lamiaceae) populations collected in Italy and Slovakia by HS-SPME, and to identify the headspace constituents responsible for the characteristic aroma impression by GC/FID and GC/MS techniques. Among more than 100 volatile components detected, the C(8) alcohol oct-1-en-3-ol, responsible for the typical mushroom-like odor, and the phenolic coumarin, with a characteristic sweet and creamy vanilla bean odor, played a major role in the aroma of whole aerial parts and different plant organ samples. In particular, dry calyx parts could be proposed as flavoring agent in food products as mushroom aroma enhancer. Multivariate chemometric techniques, such as cluster analysis and principal component analysis, were used to characterize the sample populations according to the geographical origin and processing of plant material. 相似文献
63.
Geoffrey S. Gottlieb Robert A. Smith Ndeye Mery Dia Badiane Selly Ba Stephen E. Hawes Macoumba Toure Alison K. Starling Fatou Traore Fatima Sall Stephen L. Cherne Joshua Stern Kim G. Wong Paul Lu Moon Kim Dana N. Raugi Airin Lam James I. Mullins Nancy B. Kiviat Papa Salif Sow for the UW-Dakar HIV- Study Group 《PloS one》2011,6(7)
Background
Antiretroviral therapy for HIV-2 infection is hampered by intrinsic resistance to many of the drugs used to treat HIV-1. Limited studies suggest that the integrase inhibitors (INIs) raltegravir and elvitegravir have potent activity against HIV-2 in culture and in infected patients. There is a paucity of data on genotypic variation in HIV-2 integrase that might confer intrinsic or transmitted INI resistance.Methods
We PCR amplified and analyzed 122 HIV-2 integrase consensus sequences from 39 HIV-2–infected, INI-naive adults in Senegal, West Africa. We assessed genetic variation and canonical mutations known to confer INI-resistance in HIV-1.Results
No amino acid-altering mutations were detected at sites known to be pivotal for INI resistance in HIV-1 (integrase positions 143, 148 and 155). Polymorphisms at several other HIV-1 INI resistance-associated sites were detected at positions 72, 95, 125, 154, 165, 201, 203, and 263 of the HIV-2 integrase protein.Conclusion
Emerging genotypic and phenotypic data suggest that HIV-2 is susceptible to the new class of HIV integrase inhibitors. We hypothesize that intrinsic HIV-2 integrase variation at “secondary” HIV-1 INI-resistance sites may affect the genetic barrier to HIV-2 INI resistance. Further studies will be needed to assess INI efficacy as part of combination antiretroviral therapy in HIV-2–infected patients. 相似文献64.
Lippolis R Gnoni A Abbrescia A Panelli D Maiorano S Paternoster MS Sardanelli AM Papa S Gaballo A 《Journal of Proteomics》2011,74(12):2846-2855
A comparative proteomic approach, using two dimensional gel electrophoresis and mass spectrometry, has been developed to compare and elucidate the differences among the cellular proteomes of four closely related isogenic O/C, SIN, N/R and T, B. clausii strains during both exponential and stationary phases of growth. Image analysis of the electropherograms reveals a high degree of concordance among the four proteomes, some proteins result, however, differently expressed. The proteins spots exhibiting high different expression level were identified, by mass-spectrometry analysis, as alcohol dehydrogenase (ADHA, EC1.2.1.3; ABC0046 isoform) aldehyde dehydrogenase (DHAS, EC 1.2.1.3; ABC0047 isoform) and flagellin-protein of B. clausii KSM-k16. The different expression levels of the two dehydrogenases were confirmed by quantitative RT-PCR and dehydrogenases enzymatic activity. The different patterns of protein expression can be considered as cell proteome signatures of the different strains. 相似文献
65.
Background
Neurologically, it is proven that stimulation of larger diameter fibers - e.g. using appropriate coldness, warmth, rubbing, pressure or vibration- can close the neural "gate" so that the central perception of itch and pain is reduced. This fact is based upon "Gate-control" theory of Melzack and Wall.Presentation of the hypothesis
Syringe Micro Vibrator is a new design being introduced for the first time in the field of Dentistry. This device is a promising breakthrough in pain and anxiety management and may deliver solution for clinicians plagued with patient pain phobia. It has an off-set rotating micro vibration creator with ultra high frequency and ultra low altitude that can be easily placed on any standard dental syringe and some disposable syringes. This device was registered as an invention in dentistry and received Iran National Patent number of 63765.Testing the hypothesis
By creating micro vibration, this device would be effective in reducing the pain and anxiety confronted with most types of intraoral injections as palatal, mandibular block, intraligamental and local infiltration. From the aspect of the patient pain management, this device contributes both physiologically (based on Gate Control Theory of pain) and psychologically (based on the device function as will be explained by dentist to the patient as a modern pain reducing technology). From the aspect of clinician, SMV motor provides vibrations with ultra high frequency to alleviate pain, but since it has ultra low vibration altitude, it has no adverse effect on the clinician dexterity and accuracy during injection and it does not interfere with pin point localization of injection site.Implications of the hypothesis
Upon mounting on a conventional dental anesthesia injection syringe, SMV is switched on and the clinician then uses normal injection technique to administer the anesthetic. This device is not only a useful accessory device for ordinary patients, but also more useful for pediatric patients and those who have a phobia of intraoral injection or pain. 相似文献66.
Multiple roles of matrix metalloproteinases during apoptosis 总被引:5,自引:0,他引:5
Mannello F Luchetti F Falcieri E Papa S 《Apoptosis : an international journal on programmed cell death》2005,10(1):19-24
Structural, molecular and biochemical approaches have contributed to piecing together the puzzle of how matrix metalloproteinases (MMPs) work and contribute to various disease processes. However, MMPs have many unexpected substrates other than components of the extracellular matrix which profoundly influence cell behaviour, survival and death. With the current understanding of diverse/novel roles of matrix metalloproteinases—particularly their direct or indirect relevance for the early steps during programmed cell death—some seemingly contrasting results seem less surprising. To better target MMPs an appreciation of their many extracellular, intracellular and intranuclear functions, often acting in opposing directions with paradoxical roles in cell death, is carefully required. 相似文献
67.
68.
The present paper describes the spermiogenesis and the ultrastructure of the spermatozoon of Fasciola gigantica, as revealed by transmission electron microscopy. Spermiogenesis in F. gigantica begins with the formation of a differentiation zone containing 2 centrioles with associated striated roots and an intercentriolar body between them. Each centriole develops a flagellum. Proximodistal fusion of these flagella with the median cytoplasmic extension gives rise to the spermatozoon. Spermiogenesis in F. gigantica is characterized by the formation of a dorsolateral cytoplasmic expansion, an external ornamentation of the cell membrane, and spinelike bodies. These 3 structures were also observed in the anterior part of the spermatozoon. Our study describes for the first time the simultaneous presence of dorsolateral cytoplasmic expansion, external ornamentation of the plasma membrane, and spinelike bodies in the spermatozoon of a trematode. 相似文献
69.
Babacar Diao Papa Ahmed Fall Ibrahima Bah Cyrille Ze Ondo Yoro Diallo Lamine Niang Alain Khassim Ndoye Sérigne Maguèye Gueye Mamadou Ba Bay Assane Diagne 《Andrologie》2006,16(2):131-134
Patients and Methods
This is a retrospective study of patients admitted with gunshot injuries to the external genital organs to the urology departments of Aristide Le Dantec Hospital, Grand Yoff General Hospital and Dakar Principal Hospital, between January 1998 and January 2003. The following parameters were studied: patients’ age and gender, interval between accident and admission, clinical features, complementary investigations and treatment, and early and late outcomes.Results
Only males were observed and the mean age of these patients was 37.7 years (range: 22–52 years). Lesions were accidental in five cases. Two cases of testicular wounds, two cases of corpus cavernosum injuries, two cases of urethral injury, and one case of perineal wound were observed. After excision of the lesions, complementary procedures consisted of: orchidectomy in two cases, corpus cavernosum — albuginea suture in two cases and end-to-end urethral suture in one case. Perineoscrotal wounds were sutured three days after debridement. All patients received antibiotics and antitetanus serum. No death was observed during the immediate follow-up. No case of urethral stricture or erectile dysfunction was observed with a follow-up of 18 months. Semen analysis was normal in the two cases of orchidectomy. 相似文献70.
Papa R Glagla S Danchin A Schweder T Marino G Duilio A 《Extremophiles : life under extreme conditions》2006,10(6):483-491
The capability of microorganisms to utilize different carbohydrates as energy source reflects the availability of these substrates in their habitat. Investigation of the proteins involved in carbohydrate usage, in parallel with analysis of their expression, is then likely to provide information on the interaction between microorganisms and their ecosystem. We analysed the growth behaviour of the marine Antarctic bacterium Pseudoalteromonas haloplanktis TAC125 in the presence and in the absence of different carbon source. A marked increase in the optical density was detected when l-malate was added to the growth medium. Bacterial proteins differently expressed in the presence of l-malate were identified by proteomic profiling experiments. On the basis of their relative increase, six proteins were selected for further analyses. Among these, the expression of a putative outer membrane porin was demonstrated to be heavily induced by l-malate. The presence of a functionally active two-component regulatory system very likely controlled by l-malate was found in the upstream region of the porin gene. A non functional genomic porin mutant was then constructed showing a direct involvement of the protein in the uptake of l-malate. To the best of our knowledge, the occurrence of such a regulatory system has never been reported in Pseudoalteromonads so far and might constitute a key step in the development of an effective inducible cold expression system. 相似文献