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1.
Background:  The eradication rate of first-line Helicobacter pylori treatment is only 70–85% and has been decreasing due to the increase in antibiotic resistance. The aim of this study was to evaluate the efficacy of bismuth-containing quadruple therapy as second-line treatment for H. pylori infection based on treatment duration.
Methods:  We prospectively enrolled 227 patients that were found to have persistent H. pylori infection after first-line proton-pump inhibitor-clarithromycin-amoxicillin triple therapy. Patients were randomized to 1-week (112 patients) and 2-week (115 patients) quadruple therapy with tripotassium dicitrate bismuthate 300 mg q.i.d., meteronidazole 500 mg t.i.d., and tetracycline 500 mg q.i.d. and esomeprazole 20 mg b.i.d. The eradication rate, drug compliance, and adverse events were compared based on treatment duration.
Results:  The eradication rates were 72/112 (64.3%, 95% CI: 0.504–0.830) and 71/92 (77.2%, 0.440–0.749) with 1-week group, and 95/115 (82.6%, 1.165–2.449) an 88/94 (93.6%, 1.213–5.113) with 2-week group by intention-to-treat therapy ( p  = .002) and per-protocol analysis ( p  = .001), respectively. The adverse events increased as the treatment durations increased from 7 to 14 days (20.0 and 42.5%, respectively, p  < .001). However, there was no significant difference in the patient compliance or the rate of major adverse events between the 1- and 2-week groups (6.3 and 12.5%, respectively, p  = .133).
Conclusion:  Two-week bismuth-containing quadruple therapy was more effective than the 1-week treatment, and should be considered for second-line treatment in Korea.  相似文献   

2.
Feeding ecology and prey selection of sand smelt (Atherina boyeri, Risso, 1810) were investigated by taking monthly samples (January to December 2010) at four stations of Lake E?irdir, (Turkey) using gill nets (mesh sizes 10–100 mm) and purse‐seines (mesh size 6 mm). A total of 49 out of 612 analysed stomachs were empty (8.01%); stomach contents included eight major prey categories: zooplankton, phytoplankton, Arachnida, Arthropoda, Insecta, fishes as well as unidentified organisms and remains. Dominant prey items included cladocerans (Bosmina longirostris [% N = 67.92], Alona quadrangularis [% N = 5.06]), copepods (Nitokra hibernica [% N = 9.30], Mesocyclops leuckarti [% N = 3.35]), and arthropoda (Corophium curvispinum [% N = 3.46]). The importance of Insecta, Arthropoda, fishes, and unidentified eggs increased in the diet with increasing size of the sand smelt, whereas the contribution of Cladocera and Copepoda decreased. Sand smelt strongly preferred B. longirostris (selectivity index V = 0.639, χ2 = 81.689, p < .01), N. hibernica (V = 0.205, χ2 = 8.429, p < .01), and A. quadrangularis (V = 0.159, χ2 = 5.039, p < .01) despite their low abundance in the environment. Atherina boyeri (V = ?0.699, χ2 = 97.812, p < .01), Aphanius anatoliae (V = ?0.328, χ2 = 21.463, p < .01), Insecta (V = ?0.229, χ2 = 10.497, p < .01), and Keratella cochlearis (V = ?0.265, χ2 = 14.009, p < .01) were the most abundant prey in the environment, however they were negatively selected by sand smelt. Knipowitschia caucasica, Asplanchna priodonta, Trichocerca sp., Lecane sp., and Acaridae also inhabit the lake, but were not found in the sand smelt food items. Cladocerans dominated during autumn and winter, arthropods, copepods, rotifers and phytoplankton in spring, whereas Insecta and fishes were dominant in summer.  相似文献   

3.
Abstract: A systematic account of highly diverse cyrtocrinid faunules from Upper Jurassic strata of ?tramberk type (Oxfordian–Tithonian) in southern Poland (Polish Carpathians) is presented. Fourteen taxa (Phyllocrinus malbosianus, Ph. stellaris, Ph. sp., Psalidocrinus armatus, Sclerocrinus compressus, Spolonicus sp. nov., Hemicrinus aff. kabanovi, Ancepsicrinus parvus gen. et sp. nov., Tetracrinus baumilleri sp. nov., Eugeniacrinites alexandrowiczi, E. cf. moravicus, E. sp., Eudesicrinus gluchowskii sp. nov. and Hemibrachiocrinus tithonicus sp. nov. are described and illustrated. Representatives of the genus Eudesicrinus, previously recorded only from the Lower Jurassic, are here shown to extend into the uppermost Jurassic. Other cyrtocrinids considered are common in Jurassic/Cretaceous strata across Europe. In the present faunules, isocrinid (Isocrinida), comatulid (Comatulida) and roveacrinid (Roveacrinida sensu Rasmussen, inclusive of Saccocoma) crinoids are associated.  相似文献   

4.
Background: Most treatments deemed effective for Helicobacter pylori eradication in developed countries are less effective in developing countries. Regimens containing clarithromycin, metronidazole, and amoxicillin seem efficacious despite antibiotic resistance, and may be a viable option in developing countries. Materials and Methods: We evaluated the efficacy of a 14‐day regimen with 500 mg clarithromycin b.i.d., 500 mg metronidazole t.i.d., and 500 mg amoxicillin t.i.d. (with and without a proton pump inhibitor), and a 10‐day regimen containing 500 mg clarithromycin b.i.d., 1 g amoxicillin b.i.d., and 20 mg omeprazole b.i.d. in Pasto, Colombia, using a randomized, single‐blind design stratified by presence of atrophic gastritis. Results: H. pylori was eradicated in 86.8% and 85.3% of the participants randomized to a clarithromycin‐metronidazole‐amoxicillin and clarithromycin‐amoxicillin‐omeprazole regimens, respectively (p = .79). Per‐protocol analyses indicated greater efficacy for the clarithromycin‐metronidazole‐amoxicillin regimen (97%) versus the clarithromycin‐amoxicillin‐omeprazole regimen (86%) (p = .04), particularly for participants with atrophic gastritis (clarithromycin‐metronidazole‐amoxicillin = 100%, clarithromycin‐amoxicillin‐omeprazole = 81%; p = .02). Adverse events were mild, but adverse event‐related non‐compliance was reported more often for regimens containing clarithromycin, metronidazole, and amoxicillin. Conclusions: Our results suggest that an eradication rate of > 85% can be achieved with 14‐day clarithromycin, metronidazole, and amoxicillin and 10‐day clarithromycin, amoxicillin, and omeprazole regimens in Pasto, Colombia. The regimens containing clarithromycin, metronidazole, and amoxicillin appear to be superior to the clarithromycin, amoxicillin, and omeprazole regimen for compliant participants and those with atrophic gastritis. Our findings provide treatment options for a population in a developing country with a high prevalence of H. pylori infections and antibiotic resistance.  相似文献   

5.
A new epiphytic dinoflagellate is described, G ambierdiscus scabrosus sp. nov., from tidal pools and rocky shores along the coastal areas of Japan. Cells are 63.2 ± 5.7 μm in depth, 58.2 ± 5.7 μm in width, and 37.3 ± 3.5 μm in length. The plate formula of G . scabrosus is Po, 4′, 0a, 6′′, 6c, ?s, 5′′′, 0p, and 2′′′′. Morphologically, G . scabrosus resembles G . belizeanus as follows: anterioposteriorly compressed cell shape, narrow 2′′′′ plate, and areolated surface. Despite this similarity, the cells of G . scabrosus can be distinguishable by the presence of the asymmetric shaped 3′′ plate and the rectangular shaped 2′ plate.  相似文献   

6.
In the spirit of recent calls for species delimitation studies to become more pluralistic, incorporating multiple sources of evidence, we adopted an integrative, phylogeographic approach to delimiting species and evolutionarily significant units (ESUs) in the Corallorhiza striata species complex. This rare, North American, mycoheterotrophic orchid has been a taxonomic challenge regarding species boundaries, displaying complex patterns of variation and reduced vegetative morphology. We employed plastid DNA, nuclear DNA and morphometrics, treating the C. striata complex as a case study for integrative species delimitation. We found evidence for the differentiation of the endangered Cbentleyi (eastern USA) + Cstriata var. involuta (Mexico) from the remaining Cstriata (= Cstriata s.s.; USA, Canada, Mexico). Corallorhiza striata involuta and C. bentleyi, disjunct by thousands of kilometres (Mexico‐Appalachia), were genetically identical but morphologically distinct. Evidence suggests the Cstriata complex represents three species: Cbentleyi, Cinvoluta and a widespread Cstriata s.s under operational criteria of diagnosability and common allele pools. In contrast, Bayesian coalescent estimation delimited four species, but more informative loci and a resultant species tree will be needed to place higher confidence in future analyses. Three distinct groupings were identified within Cstriata s.s., corresponding to Cstriata striata, Cstriata vreelandii, and Californian accessions, but these were not delimited as species because of occupying a common allele pool. Each comprises an ESU, warranting conservation considerations. This study represents perhaps the most geographically comprehensive example of integrative species delimitation for any orchid and any mycoheterotroph.  相似文献   

7.
Two groups of previously undescribed anaerobic, gram-positive cocci recovered from human clinical infections were characterized using phenotypic and molecular genotypic methods. Comparative genotypic analysis showed that the strains within each of these two groups were homogeneous within the group and that each group was unique within the genus Peptoniphilus. The first group is most closely related to Peptoniphilus ivorii and the second group to Peptoniphilus harei. Based on these findings we propose two novel species, Peptoniphilus coxii sp. nov. and Peptoniphilus tyrrelliae sp. nov. The type strains are P. coxii sp. nov., RMA 16757T (= JCM 16892T = CCUG 59622T = ATCC BAA-2106T) and P. tyrrelliae sp. nov., RMA 19911T (= JCM 16893T = CCUG 59621T = ATCC BAA-2105T).  相似文献   

8.
Background: Recent studies indicate a potential role of Saccharomyces boulardii in the prevention of Helicobacter pylori treatment‐related side‐effects and also in improvement of eradication rate. Our aim is to investigate the efficacy and safety of S. boulardii in the prevention of side‐effects related to H. pylori eradication. The secondary aim of the study was to define the effect of S. boulardii on the eradication success of anti‐H. pylori therapy. Materials and methods: One hundred and twenty‐four patients with H. pylori infection (male/female: 44/80, mean age: 48 ± 14.25 year) receiving 14 days of triple therapy (clarithromycin 500 mg b.i.d., amoxicillin 1000 mg b.i.d., and lansoprazole 30 mg b.i.d.) were randomly assigned to S. boulardii or placebo. Dyspeptic symptoms were recorded by using modified Glasgow Dyspepsia Questionnaire (GDQ). Side‐effect profile and tolerability were assessed using a symptom‐based questionnaire. H. pylori status was rechecked after 6 weeks after completion of eradication therapy. Results: H. pylori eradication rate, although higher in the treatment group, was statistically similar in treatment and control groups: 71% (44/62) versus 59.7% (37/62), respectively (p > .05). Nine (14.5%) patients in the treatment group and 19 (30.6%) patients in the placebo group experienced diarrhea (p < .05). Epigastric discomfort was more frequent in the control group [9 (14.5%) versus 27 (43.5%), respectively (p < .01)]. Diffuse abdominal pain, abdominal gas, taste disturbance, urticaria, nausea symptoms were similar in both groups. GDQ scores after treatment were significantly better for treatment group (mean ± SD, range: 1.38 ± 1.25 (0–5) vs. 2.22 ± 1.44 (0–6), respectively; p < .01). Conclusion: S. boulardii improved anti‐H. pylori antibiotherapy‐associated diarrhea, epigastric discomfort, and treatment tolerability. In addition, S. boulardii supplement decreased post‐treatment dyspepsia symptoms independent of H. pylori status. However, S. boulardii had no significant affect on the rate of H. pylori eradication.  相似文献   

9.
Sex ratio distortion toward females (SR trait), induced by a Wolbachia bacterium, has been reported in two species of the Ostrinia furnacalis group, viz., O. furnacalis, and O. scapulalis (Lepidoptera: Crambidae). In addition, an SR trait caused by abacterial, unidentified agent(s) is known in O. scapulalis. Here we examined the SR trait in four other species of the furnacalis group, viz., O. orientalis, O. zaguliaevi, and O. zealis from Japan, and O. nubilalis from central and eastern Europe. Wolbachia infection was detected in three O. orientalis females and in one O. zaguliaevi female, and the infection was always associated with the SR trait. In terms of wsp and ftsZ gene sequences, Wolbachia strains in O. orientalis and O. zaguliaevi were indistinguishable from each other, or from those in O. furnacalis and O. scapulalis. These findings suggest that Wolbachia strains in the four Ostrinia species are probably identical. In addition, one O. zealis female, which was negative in diagnostic PCRs for Wolbachia and general bacteria, produced an all‐female brood. This trait was very similar to the SR trait caused by abacterial agent(s) in O. scapulalis.  相似文献   

10.
Vaccines against rabbit haemorrhagic disease virus (RHDV) are commercially produced in experimentally infected rabbits. A genetically engineered and manufactured version of the major structural protein of RHDV (VP60) is considered to be an alternative approach for vaccine production. Plants have the potential to become an excellent recombinant production system, but the low expression level and insufficient immunogenic potency of plant‐derived VP60 still hamper its practical use. In this study, we analysed the expression of a novel multimeric VP60‐based antigen in four different plant species, including Nicotiana tabacum L., Solanum tuberosum L., Brassica napus L. and Pisum sativum L. Significant differences were detected in the expression patterns of the novel fusion antigen cholera toxin B subunit (CTB)::VP60 (ctbvp60SEKDEL) at the mRNA and protein levels. Pentameric CTB::VP60 molecules were only detected in N. tabacum and P. sativum, and displayed equal levels of CTB, at approximately 0.01% of total soluble protein (TSP), and traces of detectable VP60. However, strong enhancement of the CTB protein content via self‐fertilization was only observed in P. sativum, where it reached up to 0.7% of TSP. In rabbits, a strong decrease in the protective vaccine dose required from 48–400 µg potato‐derived VP60 [ Castanon, S., Marin, M.S., Martin‐Alonso, J.M., Boga, J.A., Casais, R., Humara, J.M., Ordas, R.J. and Parra, F. (1999) Immunization with potato plants expressing VP60 protein protects against rabbit hemorrhagic disease virus. J. Virol. 73 , 4452–4455; Castanon, S., Martin‐Alonso, J.M., Marin, M.S., Boga, J.A., Alonso, P., Parra, F. and Ordas, R.J. (2002) The effect of the promoter on expression of VP60 gene from rabbit hemorrhagic disease virus in potato plants. Plant Sci. 162 , 87–95] to 0.56–0.28 µg antigenic VP60 (measured with VP60 enzyme‐linked immunosorbent assay) of crude CTB::VP60 pea extracts was demonstrated. Rabbits immunized with pea‐derived CTB::VP60 showed anti‐VP60‐specific antibodies, similar to RikaVacc®‐immunized rabbits, and survived RHDV challenge.  相似文献   

11.
The new benthic toxic dinoflagellate, Ostreopsis fattorussoi sp. nov., is described from the Eastern Mediterranean Sea, Lebanon and Cyprus coasts, and is supported by morphological and molecular data. The plate formula, Po, 3′, 7″, 6c, 7s, 5?, 2′′′′, is typical for the Ostreopsis genus. It differs from all other Ostreopsis species in that (i) the curved suture between plates 1′ and 3′ makes them approximately hexagonal, (ii) the 1′ plate lies in the left half of the epitheca and is obliquely orientated leading to a characteristic shape of plate 6″. The round thecal pores are bigger than the other two Mediterranean species (O. cf. ovata and O. cf. siamensis). O. fattorussoi is among the smallest species of the genus (DV: 60.07 ± 5.63 μm, AP: 25.66 ± 2.97 μm, W: 39.81 ± 5.05 μm) along with O. ovata. Phylogenetic analyses based on the LSU and internal transcribed spacer rDNA shows that O. fattorussoi belongs to the Atlantic/Mediterranean Ostreopsis spp. clade separated from the other Ostreopsis species. Ostreopsis fattorussoi produces OVTX‐a and structural isomers OVTX‐d and ‐e, O. cf. ovata is the only other species of this genus known to produce these toxins. The Lebanese O. fattorussoi did not produce the new palytoxin‐like compounds (ovatoxin‐i, ovatoxin‐j1, ovatoxin‐j2, and ovatoxin‐k) that were previously found in O. fattorussoi from Cyprus. The toxin content was in the range of 0.28–0.94 pg · cell?1. On the Lebanon coast, O. fattorussoi was recorded throughout the year 2015 (temperature range 18°C–31.5°C), with peaks in June and August.  相似文献   

12.
Heliosperma oliverae Niketić & Stevanović is described from Mt. Prokletije in south-west Serbia and north-east Montenegro, together with an estimation of its ecological preferences and International Union for Conservation of Nature and Natural Resources (IUCN) threat status. A map and illustration are provided. It is compared with seven closely related Balkan endemic taxa: H. macranthum Panić, H. retzdorffianum K. Malý, H. tommasinii Vis., H. insulare Trinajstić, H. chromodontum (Boiss. & Reuter) Juratzka, H. intonsum (Greuter & Melzh.) Niketić & Stevanović, and H. nikolicii (Seliger & T. Wraber) Niketić & Stevanović. An amended key to species and a table showing differences from the related Balkan taxa are also provided.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 154 , 55–63.  相似文献   

13.
The chromosome number and morphology of eight species belonging to the section Santolinoideae of the genus Achillea L. (Asteraceae) were investigated using karyological techniques. The species studied were Achillea cucullata (Hausskn.) Bornm., A. vermicularis Trin., A. monocephala Boiss. & Bal., A. boissieri (Hausskn.) Bornm., A. santolina L., A. gypsicola Hub.-Mor., A. goniocephala Boiss. & Bal., and A. spinulifolia Fenzl ex Boiss. In these species, the chromosome numbers were 2 n  = 18 in A. vermicularis , A. monocephala , and A. boissieri , 2 n  = 18A + 1B in A. spinulifolia , 2 n  = 36 in A. cucullata and A. santolina , and 2 n  = 54 in A. gypsicola and A. goniocephala . All of the chromosomes had median point (M), median region (m), or submedian (sm) centromeres. An increase in asymmetry was not observed in the karyotypes of the species.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 573–580.  相似文献   

14.
Mycobacteriosis, caused by the intracellular parasitism Mycobacterium sp., causes economic damages to aquaculture production in Japan, particularly in seriola fish production. Antibiotics are not effective against Mycobacterium sp. and so a potent vaccine is needed. We previously reported that BCG vaccine (Mycobacterium bovis BCG) induces adaptive immunity against Mycobacterium sp. in Japanese flounder, Paralichthys olivaceus. In a phylogenetic tree, the genes for a major antigen, the Ag85 complex, in Mycobacterium sp. TUMSAT-Msp001 are closely related to homologues in Mycobacterium ulcerans. M. bovis BCG was detected until 7 days post-injection at the injection site (muscle) and 28 days post-vaccination in spleen. Cumulative mortality of amberjack, Seriola dumerili vaccinated intramuscularly (i.m.) and intraperitoneally (i.p.) with M. bovis BCG was 32.3% and 59.5% respectively, at 24 days post-infection of Mycobacterium sp., compared to 97.8% in PBS-injected fish. The bacterial counts of Mycobacterium sp. in spleen of both i.m.-and i.p.-vaccinated fish (6.2 × 103 and 1.3 × 104 CFU/mg tissue, respectively) at 20 days post-infection were significantly lower (P < 0.01) than those of PBS-injected fish (8.0 × 106 CFU/mg). Furthermore, Immersion challenge with Mycobacterium sp. TUMSAT Msp-001 showed 50% RPS value in BCG i.m.-vaccinated fish at the end of the experiment. These results support our previous study using Japanese flounder and suggest that BCG vaccine is also effective against Mycobacterium sp. infection in amberjack.  相似文献   

15.
The main objective of this study was to investigate the population structure, length–weight relationship (LWR) and growth of white seabream, Diplodus sargus sargus (L., 1758) in Beymelek Lagoon, Turkey. Samples were collected by gill‐ and trammel nets of various mesh sizes, February 2006 to January 2007. A total of 355 specimens (51 males; 34 females; 270 unidentified) were collected. Male to female ratio was 1.50 : 1. Ages ranged from 0 to 3 years; about 70% were juveniles. Most fish were between 13 and 16 cm in total length and below 90 g in weight. The LWR of all individuals was W = 0.0140 × L3.1028. The von Bertalanffy growth equation was calculated as Lt = 39.9 × [1 – exp(?0.268 × (t + 1.753)] and the growth performance index (Φ′) was 6.056.  相似文献   

16.
Abstract  The Australasian genus Scotocyma Turner is revised, containing the species S. albinotata (Walker), S. legalis (Warren), S. asiatica Holloway, S. scotopepla Prout, stat. n., S. manusensis Prout, stat. n., S. mimula (Warren), stat. n. and S. miscix Prout. Scotocyma euryochra Turner, syn. n., S. idioschema Turner, syn. n., S. ischnophrica Turner, syn. n. and S. transfixa Turner, syn. n. are regarded as synonyms of S. albinotata . Four species are described as new: S. samoensis , sp. n., S. sumatrensis , sp. n., S. rutilimixta , sp. n. and S. longiuncus , sp. n. Lectotypes are designated for S. scotopepla , S. manusensis and S. miscix . All species are illustrated, and keys to species and distribution maps are provided. A phylogenetic analysis was performed to test the monophyly of the genus and to examine distribution patterns of the species. A biogeographical discussion is included. The tribal position of the genus is clarified and relationships to closely related genera are discussed.  相似文献   

17.
Fucus and Laminaria species, dominant seaweeds in the intertidal and subtidal zones of the temperate North Atlantic, experience tidal cycles that are not synchronized with light:dark (L:D) cycles. To investigate how nutrient assimilation is affected by light cycles, the activity of nitrate reductase (NR) was examined in thalli incubated in outdoor tanks with flowing seawater and natural L:D cycles. NR activity in Laminaria digitata (Huds.) Lamour. showed strong diel patterns with low activities in darkness and peak activities near midday. This diel pattern was controlled by light but not by a circadian rhythm. In contrast, there was no diel variation in NR activity in Fucus serratus L., F. vesiculosus (L.) Lamour., and F. spiralis L. either collected directly from the shore or maintained in the outdoor tanks. In laboratory cultures, transfer to continuous darkness suppressed NR activity in L. digitata, but not in F. vesiculosus; continuous light increased NR activity in L. digitata but decreased activity in F. vesiculosus. Furthermore, 4 d enrichment with ammonium (50 μmol · L?1 pulses), resulted in NR activity declining by >80% in L. digitata, but no significant changes in F. serratus. Seasonal differences in maximum NR activity were present in both genera with activities highest in late winter and lowest in summer. This is the first report of NR activity in any alga that is not strongly regulated by light and ammonium. Because light and tidal emersion do not always coincide, Fucus species may have lost the regulation of NR by light that has been observed in other algae and higher plants.  相似文献   

18.
Background. Cyclooxygenase (COX)‐2 induced by Helicobacter pylori is thought to enhance gastric carcinogenesis by affecting the maintenance of epithelial homeostasis. Materials and Methods. Gastric biopsies from 160 subjects, 97 with nonulcer dyspepsia (47 H. pylori negative, 50 H. pylori positive) and 63 with gastric cancer were examined immunohistochemically for COX‐2 expression, cell proliferation and apoptotic indices. Results. COX‐2 expression in corpus was significantly higher in H. pylori positive than in negative non‐ulcer dyspepsia (NUD) (p < .05). Regardless of site, gastric cancer subjects had higher COX‐2 expression in both antrum and corpus compared with H. pylori negative and positive NUD (p < .005). Proliferation was higher in cancer and H. pylori positive than in negative NUD (p < .0001). Moreover, cancer had enhanced proliferation than H. pylori positive NUD in corpus greater (p = .0454) and antrum lesser (p = .0215) curvatures. Apoptosis was higher in H. pylori positive than in negative NUD (p < .05). However, both had a higher index than the cancer subjects (p < .0001). Apoptosis : proliferation ratio was higher in corpus of H. pylori negative than in positive NUD in greater (p = .0122) and lesser (p = .0009) curvatures. However, both had a higher A:P ratio than cancer cases (p = .0001). A negative correlation between COX‐2 expression and A:P ratio was found in corpus greater (r = –.176, p= .0437) and lesser (r = –.188, p= .0312) curvatures. Conclusion. The expression of COX‐2 is associated with disruption in gastric epithelial kinetics and hence may play a role in gastric carcinogenesis.  相似文献   

19.
Spectroscopy information (functional groups and semiquantitative data) by Fourier transform infrared (FTIR) spectroscopy of Spongiophyton Kräusel emend. Chaloner et al. is reported for the first time, in an attempt to identify spectroscopic patterns that would differentiate species of these taxa. A total of 33 specimens identified as S. lenticularis, S. nanum and S. minutissimum and preserved as compressions were analysed. They come from the same fossiliferous horizon of one outcrop situated in the uppermost Middle Devonian São Domingos Formation of the Paraná Basin in southern Brazil. The results reveal that functional groups in the 3000–2800 and 1800–700 cm?1 wavenumber regions are present in all specimens. Infrared‐derived ratios (CH2/CH3, Al/Ox, Ox1/Ox2, C=O cont., C=C cont., Al2 and Ar/Al) and types of kerogen led to a comparison of the morphological characteristics of the studied material and indicate that compressions of S. lenticularis, S. nanum and S. minutissimum contain different organic compounds. S. nanum and S. minutissimum show higher oxidation and lower aromaticity of its organic matter than S. lenticularis. Additionally, S. lenticularis shows low A‐factor values, suggesting a composition similar to type III kerogen, while S. nanum and S. minutissimum showed intermediate to high A‐factor values, suggesting a composition similar to type II kerogen. In conclusion, the chemical‐analytical techniques and statistical analysis (using PCA technique) reveal a closer taxonomic relationship between S. nanum and S. minutissimum than either has with S. lenticularis, supporting their taxonomic separation, previously proposed in the literature on the basis of morphological features. Lastly, the chemical signatures support the hypothesis that links these enigmatic fossils to a type of lichen or other early inland plant.  相似文献   

20.
Introduction –  Lawsonia inermis L. is a natural red colouring agent, commonly named “Henna”, which is used to dye skin and hair. The aim of this study was to evaluate the quality of L. inermis that is commercially available as a raw plant material or preparation in order to guarantee good quality products. Objective ?  To develop a simple protocol for the qualification of different samples labelled as L. inermis by using the HPTLC densitometry method and to identify possible adulterations with other plants. Methodology ?  Samples of leaves of L. inermis were extracted with methanol. Two chromatographic methods were developed to determine the chemical fingerprinting of L. inermis. The first was based on HPTLC identification followed by densitometric measurements at 337 nm. The second was based on RP‐HPLC separation with gradient elution and photodiode array detection at 337 nm. Samples of Cassia obovata Collad., and Indigofera tinctoria L., were treated in the same way. Results –  The simplicity of the sample preparation, and the possibility of analysing several samples of herbal products simultaneously in a short time, make HPTLC the method of choice. The HPTLC method was feasible for the comprehensive quality evaluation of herbal products. From the comparison of their “fingerprint”, it was possible to detect substitution of plants that are different from those declared on the label. Conclusion ?  The HPTLC may be used as a rapid method by which to control the quality of raw plant materials and formulations based on the title plant. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

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