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1.

Purpose

To investigate the thickness of the retinal layers and to assess the prevalence of macular microcysts (MM) in the inner nuclear layer (INL) of patients with mitochondrial optic neuropathies (MON).

Methods

All patients with molecularly confirmed MON, i.e. Leber’s Hereditary Optic Neuropathy (LHON) and Dominant Optic Atrophy (DOA), referred between 2010 and 2012 were enrolled. Eight patients with MM were compared with two control groups: MON patients without MM matched by age, peripapillary retinal nerve fiber layer (RNFL) thickness, and visual acuity, as well as age-matched controls. Retinal segmentation was performed using specific Optical coherence tomography (OCT) software (Carl Zeiss Meditec). Macular segmentation thickness values of the three groups were compared by one-way analysis of variance with Bonferroni post hoc corrections.

Results

MM were identified in 5/90 (5.6%) patients with LHON and 3/58 (5.2%) with DOA. The INL was thicker in patients with MON compared to controls regardless of the presence of MM [133.1±7μm vs 122.3±9μm in MM patients (p<0.01) and 128.5±8μm vs. 122.3±9μm in no-MM patients (p<0.05)], however the outer nuclear layer (ONL) was thicker in patients with MM (101.4±1mμ) compared to patients without MM [77.5±8mμ (p<0.001)] and controls [78.4±7mμ (p<0.001)]. ONL thickness did not significantly differ between patients without MM and controls.

Conclusion

The prevalence of MM in MON is low (5-6%), but associated with ONL thickening. We speculate that in MON patients with MM, vitreo-retinal traction contributes to the thickening of ONL as well as to the production of cystic spaces.  相似文献   
2.
The morphogenic response of somatic (leaf and petiole) and de-differentiated tissue (callus) of two blackberry (Rubus fruticosus) and one raspberry (Rubus idaeus) cultivars have been studied in vitro. With the aim to induce regeneration the effect of two sets of plant growth regulator (PGR) combinations (high cytokinin/auxin ratios and high auxin/cytokinin ratios) in Murashige and Skoog basal medium, were analysed. The three cultivars were characterised by a qualitatively different morphogenic response to the PGR combinations. Raspberry adventitious shoot regeneration from somatic tissue was improved by the 6-benzylaminopurine (BAP)/indol-3-butyric acid (IBA) combinations. On the contrary, shoot regeneration of both blackberry cultivars was reduced by high concentrations of BAP and completely inhibited by BAP/IBA combination. Media supplemented with high auxin/cytokinin ratios promoted callus production and root differentiation according to genotype and type of auxin. All the genotypes responded to media supplemented with IBA. 2,4-dichlorophenoxyacetic acid induced good callus formation in blackberry, but was toxic to raspberry. Indirect shoot formation was observed only in callus of blackberry cultivar Hull Thornless cultivated on medium with 10 μM BAP, the same concentration able to trigger efficient direct shoot regeneration from leaf explants of the same cultivar. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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The fluorescence properties of the single tryptophanyl residue present in amicyanin from Thiobacillus versutus are very similar to those of azurin from Pseudomonas aeruginosa and other mononuclear blue copper proteins. The emission maximum is well structured and centered at 318 nm. The quantum yield is strongly affected by the presence of copper, the removal of which is accompanied by a more than sixfold increase in fluorescence, without change in shape. The fluorescence decay of holo-amicyanin is heterogeneous with a longer component of 5.7 ns and a shorter one of 0.7 ns accounting for 90% of the total emitting molecules. Copper-free amicyanin shows instead a single exponential decay (3.3 ns) of intrinsic fluorescence. This lifetime decreases as the temperature increases as does the longer lifetime component of holoamicyanin.  相似文献   
5.
Sera and blood from cattle and sheep were examined for the presence of Babesia and Theileria spp by microscopy and serology at the Parasitology Department of the Istituto Zooprofilattico Sperimentale of Abruzzo and Molise (IZSAM). Of the 47 bovine herds (323 animals) tested, 15 were found positive for Babesia bigemina and 1 for Babesia bovis. Two outbreaks occurred, one caused by B. bigemina and one by B. bovis. The B. bigemina outbreak occurred in Abruzzo and has been followed for two years. The isolate of B. bigemina was very pathogenic leading to the death of two cows out of 57. The vector responsible of the transmission appeared to be Rhipicephalus bursa. Parasites were observed in the erythrocytes for 30 days whereas sera were positive to indirect immunofluorescence (IFA) for at least one year. The B. bovis outbreak occurred in the province of Mantova (Northern Italy) in a group of 70 beef cattle imported from France. The infection resulted in the death of 5 animals and severe illness in another 6. In contrast with what occurred for Babesia infection, no clinical cases were recorded in cattle when species of Theileria were detected by microscopy. Of the 24 bovine herds (252 animals) tested for Theileria, 21 were found positive for the T. "sergenti"/buffeli/orientalis group. Single and mixed infection of T. "sergenti" and T. buffeli/orientalis were detected in herds of cross-bred cattle from Abruzzo and Marche. The parasites were identified by using a polymerase chain reaction which amplified DNA encoding p32/34. Most of the collected ticks (90%) were adults of R. bursa whereas the others were adults of Hyalomma detritum. During the period the animals have been observed (18 months), no clinical cases have been recorded and no associations have been found between blood abnormalities and animals found infected with Theileria. Prevalences of subclinically infected carriers increased from February till December (95.4%) even if the animals were indoors and no ticks were present. The prevalence then dropped dramatically six months later (76.7%). In calves less than 1 year old, the prevalence of infection significantly (p<0.05) increased with age, however intraerythrocytic stages of Theileria were found in the blood of three newborn calves (<7 days of age). Of the 18 ovine flocks tested for Babesia spp. (150 animals examined), 1 was positive for B. ovis and 2 for B. motasi. B. motasi infection was not associated with symptoms, while an outbreak of babesiosis caused by B. ovis occurred in Abruzzo. The infection resulted in the death of 3 animals (0.75% of the flock), two rams (20% of the total number) and a ewe, and severe illness in another 5 ewes (2% of the flock). Specimens of R. bursa and R. turanicus were collected from the infected animals. Of the 18 flocks (150 animals) examined, 12 were microscopically positive for Theileria spp. No clinical cases were recorded and identification at species level was not possible on the basis of morphological criteria. The prevalence distribution of infected herds and infected animals within herds and flocks have been calculated by a Monte Carlo simulation model, running 10,000 iterations. The most likely levels of prevalence of infected herds and infected animals within herds found for the species observed were as follows: 20% for B. bigemina with a prevalence within herd of 27%, 11% for B. bovis (18% within herd), 10% for Babesia ovis (19% within herd), 10% for B. motasi (17.5% within herd), 63% for Theileria in cattle (66% within herd) and 51% for Theileria in sheep (55% within herd).  相似文献   
6.
Among the enzymes involved in the life cycle of HCV, the non-structural protein NS3, with its double function of protease and NTPase/helicase, is essential for the virus replication. Exploiting our previous knowledge in the development of nucleotide-mimicking NS3 helicase (NS3h) inhibitors endowed with key structural and electronic features necessary for an optimal ligand-enzyme interaction, we developed the tetrahydroacridinyl derivative 3a as the most potent NS3h competitive inhibitor reported to date (HCV NS3h K(i)=20 nM).  相似文献   
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The alien Asian gastropod Rapana venosa (Valenciennes 1846) was first recorded in 1973 along the Italian coast of the Northern Adriatic Sea. Recently, this predator of bivalves has been spreading all around the world oceans, probably helped by ship traffic and aquaculture trade. A caging experiment in natural environment was performed during the summer of 2002 in Cesenatico (Emilia-Romagna, Italy) in order to estimate consumption rates and prey preference of R. venosa. The prey items chosen were the Mediterranean mussel Mytilus galloprovincialis (Lamarck 1819), the introduced carpet clam Tapes philippinarum (Adams and Reeve 1850), both supporting the local fisheries, and the Indo-Pacific invasive clam Anadara (Scapharca) inaequivalvis (Bruguière 1789). Results showed an average consumption of about 1 bivalve prey per day (or 1.2 g wet weight per day). Predation was species and size selective towards small specimens of A. inaequivalvis; consumption of the two commercial species was lower. These results might reduce the concern about the economical impact on the local bivalve fishery due to the presence of the predatory gastropod. On the other hand, selective predation might probably alter local community structure, influencing competition amongst filter feeder/suspension feeder bivalve species and causing long-term ecological impact. The large availability of food resource and the habitat characteristics of the Emilia-Romagna littoral makes this area an important breeding ground for R. venosa in the Mediterranean Sea, thus worthy of consideration in order to understand the bioinvasion ecology of this species and to control its likely further dispersal.  相似文献   
9.
A central nervous system (CNS) infection, such as meningitis, is a serious and life-threatening condition. Bacterial meningitis can be severe and may result in brain damage, disability or even death. Rapid diagnosis of CNS infections and identification of the pathogenic microorganisms are needed to improve the patient outcome. Bacterial culture of a patient??s cerebrospinal fluid (CSF) is currently considered the ??gold standard?? for diagnosing bacterial meningitis. From the CSF cultures researchers can assess the in vitro susceptibility of the causative microorganism to determine the best antibiotic treatment. However, many of the culture assays, such as microscopy and the latex agglutination test are not sensitive. To enhance pathogen detection in CSF samples we developed a multi-target real-time PCR assay that can rapidly identify six different microorganisms: Streptococcus pneumoniae, Neisseria meningitidis, Haemophilus influenzae, Streptococcus agalactiae, Listeria monocytogenes and Cryptococcus neoformans. In this study we applied this PCR analysis to 296 CSF samples from patients who were suspected of having meningitis. Of the 296 samples that were examined, 59 samples were positive according to the CSF culture and/or molecular assays. Forty-six CSF samples were positive for both the CSF culture and our real-time PCR assay, while 13 samples were positive for the real-time PCR but negative for the traditional assays. This discrepancy may have been caused by the fact that these samples were collected from 23 patients who were treated with antimicrobials before CSF sampling.  相似文献   
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