73 resultados para Morphological modification


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Biomarkers of blood lipid modification and oxidative stress have been associated with increased cardiovascular morbidity. We sought to determine whether these biomarkers were related to functional indices of stenosis severity among patients with stable coronary artery disease. We studied 197 consecutive patients with stable coronary artery disease due to single vessel disease. Fractional flow reserve (FFR) ≤ 0.80 was assessed as index of a functionally significant lesion. Serum levels of secretory phospholipase A2 (sPLA2) activity, secretory phospholipase A2 type IIA (sPLA2-IIA), myeloperoxydase (MPO), lipoprotein-associated phospholipase A2 (Lp-PLA2), and oxidized low-density lipoprotein (OxLDL) were assessed using commercially available assays. Patients with FFR > 0.8 had higher sPLA2 activity, sPLA2 IIA, and OxLDL levels than patients with FFR ≤ 0.8 (21.25 [16.03-27.28] vs 25.85 [20.58-34.63] U/mL, p < 0.001, 2.0 [1.5-3.4] vs 2.6 [2.0-3.4] ng/mL, p < 0.01; and 53.0 [36.0-71.0] vs 64.5 [50-89.25], p < 0.001 respectively). Patients with FFR > 0.80 had similar Lp-PLA2 and MPO levels versus those with FFR ≤ 0.8. sPLA2 activity, sPLA2 IIA significantly increased area under the curve over baseline characteristics to predict FFR ≤ 0.8 (0.67 to 0.77 (95 % confidence interval [CI]: 0.69-0.85) p < 0.01 and 0.67 to 0.77 (95 % CI: 0.69-0.84) p < 0.01, respectively). Serum sPLA2 activity as well as sPLA2-IIA level is related to functional characteristics of coronary stenoses in patients with stable coronary artery disease.

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Pleistocene glacial and interglacial periods have moulded the evolutionary history of European cold-adapted organisms. The role of the different mountain massifs has, however, not been accurately investigated in the case of high-altitude insect species. Here, we focus on three closely related species of non-flying leaf beetles of the genus Oreina (Coleoptera, Chrysomelidae), which are often found in sympatry within the mountain ranges of Europe. After showing that the species concept as currently applied does not match barcoding results, we show, based on more than 700 sequences from one nuclear and three mitochondrial genes, the role of biogeography in shaping the phylogenetic hypothesis. Dating the phylogeny using an insect molecular clock, we show that the earliest lineages diverged more than 1 Mya and that the main shift in diversification rate occurred between 0.36 and 0.18 Mya. By using a probabilistic approach on the parsimony-based dispersal/vicariance framework (MP-DIVA) as well as a direct likelihood method of state change optimization, we show that the Alps acted as a cross-roads with multiple events of dispersal to and reinvasion from neighbouring mountains. However, the relative importance of vicariance vs. dispersal events on the process of rapid diversification remains difficult to evaluate because of a bias towards overestimation of vicariance in the DIVA algorithm. Parallels are drawn with recent studies of cold-adapted species, although our study reveals novel patterns in diversity and genetic links between European mountains, and highlights the importance of neglected regions, such as the Jura and the Balkanic range.

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The concept of cellular schwannoma as an unusual benign tumor is well established for peripheral nerves but has never been tested in neurosurgical series. In order to test the validity of this concept in cranial nerves and spinal roots we performed an analysis of the clinical and morphological characteristics of 12 cellular and 166 classical benign schwannomas. Immunohistochemical detection of antigen expression in Schwann cells including proliferating cell nuclear antigen (PCNA) was also performed. This study shows that cellular schwannomas in neurosurgical series manifest at a lower age than the classical benign variant and occur mainly in the spinal roots. Mitotic activity and sinusoidal vessels appear more frequently in cellular schwannomas and constitute with high cellularity, the most valuable criteria separating both entities. The postoperative course in both types of tumors was free of metastases or sarcomatous changes. Immunoexpression of S-100 protein, vimentin, epithelial membrane antigen and glial fibrillary acidic protein is not statistically different between the two variants. In contrast, PCNA is more highly expressed in cellular schwannomas. These These results confirm the concept that cellular schwannomas are a clinico-pathological variant of benign schwannomas and provide significant support for the introduction of this entity in neurosurgical oncology.

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OBJECTIVE: To evaluate morphological and perfusion changes in liver metastases of neuroendocrine tumours by contrast-enhanced ultrasound (CEUS) after transarterial embolisation with bead block (TAE) or trans-arterial chemoembolisation with doxorubicin-eluting beads (DEB-TACE). METHODS: In this retrospective study, seven patients underwent TAE, and ten underwent DEB-TACE using beads of the same size. At 1 day before embolisation, 2 days, 1 month and 3 months after the procedure, a destruction-replenishment study using CEUS was performed with a microbubble-enhancing contrast material on a reference tumour. Relative blood flow (rBF) and relative blood volume (rBV) were obtained from the ratio of values obtained in the tumour and in adjacent liver parenchyma. Morphological parameters such as the tumour's major diameter and the viable tumour's major diameter were also measured. A parameter combining functional and morphological data, the tumour vitality index (TVI), was studied. The Wilcoxon rank-sum test and Fisher's test were used to compare treatment groups. RESULTS: At 3 months rBF, rBV and TVI were significantly lower (P = 0.005, P = 0.04 and P = 0.03) for the group with doxorubicin. No difference in morphological parameters was found throughout the follow-up. CONCLUSIONS: One parameter, TVI, could evaluate the morphological and functional response to treatments.

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Targeted mutagenesis directed by oligonucleotides (ONs) is a promising method for manipulating the genome in higher eukaryotes. In this study, we have compared gene editing by different ONs on two new target sequences, the eBFP and the rd1 mutant photoreceptor betaPDE cDNAs, which were integrated as single copy transgenes at the same genomic site in 293T cells. Interestingly, antisense ONs were superior to sense ONs for one target only, showing that target sequence can by itself impart strand-bias in gene editing. The most efficient ONs were short 25 nt ONs with flanking locked nucleic acids (LNAs), a chemistry that had only been tested for targeted nucleotide mutagenesis in yeast, and 25 nt ONs with phosphorothioate linkages. We showed that LNA-modified ONs mediate dose-dependent target modification and analyzed the importance of LNA position and content. Importantly, when using ONs with flanking LNAs, targeted gene modification was stably transmitted during cell division, which allowed reliable cloning of modified cells, a feature essential for further applications in functional genomics and gene therapy. Finally, we showed that ONs with flanking LNAs aimed at correcting the rd1 stop mutation could promote survival of photoreceptors in retinas of rd1 mutant mice, suggesting that they are also active in vivo.

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Introduction: Clinical symptoms and degree of spinal stenosis based on cross sectional dural sac area correlate only weakly in lumbar spinal stenosis (LSS) patients. We conceived a four grade classification system (A, B, C & D) based on the morphology of the dural sac and its contents as seen on T2 axial MRI images. The categories take into account the rootlet/CSF ratio. We applied this grading to three patient groups: LSS scheduled for surgery; LSS following conservative treatment and patients with low back pain (LBP) without leg pain. Materials/Methods: A total of 346 T2 axial MRI images taken from LSS and LBP patients were included in this retroperspective study. 37 patients had decompressive surgery (132 MRI images), 31 conservative treatment (116 MRI images) and 27 patients had unspecific LBP (98 MRI images). Dural sac cross-sectional surface area and morphological grading of the canal were measured digitally both at disc and pedicle level. Intra- and inter-observer reliability were assessed (weighted Cohen's kappa statistics) from 50 MRI images taken from the surgery group. Results: At the most severe disc level, grade A (mild stenosis) was found in 3% of MRI images of the surgical group as opposed to 51% in the conservatively treated group and 85% in the LBP group. Grade B occurred in 8% of the surgical, 20% of the conservative and was negligible in LBP group (below 1%). Grade C and D (severe stenosis) was found in 89% of the surgical group, as opposed to 30% in conservative group and 11% in LBP group. The grades of all groups were comparable at the pedicle levels, exhibiting in 94% a grade A with a maximum at the A1 grade. Pedicle and disc level cross-sectional area were smallest in the surgery group and smaller in the conservative group as compared to the LBP group at the levels L2, L3 and L4. According to cross-sectional area measurements patients from the surgery group seems to have smaller vertebral canal although this was not related to smaller stature. Validation of grading: Average intra-and inter observer kappas were 0.76 and 0.69 respectively, for physicians working in the study originating institution. Combining all observers the kappa values were 0.57 +/- 0.19. and 0.44 +/- 0.19 respectively. Dural sac cross-sectional area measurements showed no statistically significant differences between observers. Conclusion: Since no specific measurement tools are needed the grading suits everyday clinical practice and favours communication of degree of stenosis between practising physicians. In our institution Grade A stenosis was less likely to require surgical treatment. This grading can therefore be an aid in surgical patient selection in teaching units.

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BACKGROUND: As embryo selection is not allowed by law in Switzerland, we need a single early scoring system to identify zygotes with high implantation potential and to select zygotes for fresh transfer or cryopreservation. The underlying aim is to maximize the cumulated pregnancy rate while limiting the number of multiple pregnancies. METHODS: In all, 613 fresh and 617 frozen-thawed zygotes were scored for proximity, orientation and centring of the pronuclei, cytoplasmic halo, and number and polarization of the nucleolar precursor bodies. From these individual scores, a cumulated pronuclear score (CPNS) was calculated. Correlation between CPNS and implantation was examined and compared between fresh and frozen-thawed zygotes. The effect of freezing on CPNS was also investigated. RESULTS: CPNS was positively associated with embryo implantation in both fresh and frozen zygotes. With similar CPNS, frozen zygotes presented implantation rates as high as those of fresh zygotes. Nucleolar precursor bodies pattern and cytoplasmic halo appeared as the most important factors predictive of implantation for both types of zygotes, while pronuclei position was specifically relevant for frozen-thawed zygotes. Freezing induced an alteration of most zygote parameters, resulting in a significantly lower CPNS and a lower pregnancy rate. CONCLUSIONS: CPNS may be used as a single prognostic tool for implantation of both fresh and frozen-thawed zygotes. Lower CPNS values of frozen-thawed zygotes may also be indicative of freezing damage to zygotes. Successful implantation of frozen zygotes despite lower CPNS suggests that they may recover after thawing and in vitro culture.

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The actual geographic distribution of the two sibling mouse-eared bat species Myotis myotis and Myotis blythii, which occur widely sympatrically in the western Palaearctic region, remains largely controversial. This concerns particularly the specific attribution of marginal populations from the Mediterranean islands and from adjacent areas of North Africa and Asia, which are morphologically intermediate between continental M. myotis and M. blythii from Europe. This study attempts to clarify this question by using four different approaches: cranial morphology, external morphology, genetics and trophic ecology. The three latter methods show unambiguously that North Africa, Malta, Sardinia and Corsica are presently inhabited by monospecific populations of M. myotis. In contrast, cranial morphometrics do not yield conclusive results. These results contradict all recent studies, which attribute North African and Maltese mouse-eared bats to M. blythii and consider that Sardinia and Corsica harbour sympatric populations of the two species. As concerns south-eastern populations, doubts are also expressed about the attribution of the subspecific taxon omari which may actually refer to M. myotis instead of M. blythii. Protein electrophoresis is presently the only absolute method available for determining M. myotis and M. blythii throughout their distribution ranges. However, species identification may be approached by relying on less sophisticated morphometrical methods as presented in this study. Species-specific habitat specializations are probably responsible for the differences observed between the geographic distributions of M. myotis and M. blythii, as they provide a logical groundwork for a coherent model of speciation for these two bat species.

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Neurofilament (NF) proteins consist of three subunits of different molecular weights defined as NF-H, NF-M, and NF-L. They are typical structures of the neuronal cytoskeleton. Their immunocytochemical distribution during postnatal development of cat cerebellum was studied with several monoclonal and polyclonal antibodies against phosphorylated or unmodified sites. Expression and distribution of the triplet neurofilament proteins changed with maturation. Afferent mossy and climbing fibers in the medullary layer contained NF-M and NF-L already at birth, whereas NF-H appeared later. Within the first three postnatal weeks, all three subunits appeared in mossy and climbing fibers in the internal granular and molecular layers and in the axons of Purkinje cells. Axons of local circuit neurons such as basket cells expressed these proteins at the end of the first month, whereas parallel fibers expressed them last, at the beginning of the third postnatal month. Differential localization was especially observed for NF-H. Depending on phosphorylation, NF-H proteins were found in different axon types in climbing, mossy, and basket fibers or additionally in parallel fibers. A nonphosphorylated NF-H subunit was exclusively located in some Purkinje cells at early developmental stages and in some smaller interneurons later. A novel finding is the presence of a phosphorylation site in the NF-H subunit that is localized in dendrites of Purkinje cells but not in axons. Expression and phosphorylation of the NF-H subunit, especially, is cell-type specific and possibly involved in the adult-type stabilization of the axonal and dendritic cytoskeleton.

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Introduction: In normal mice, lentiviral vector (LV) shows a great efficiency to infect the RPE cells, but transduces retinal neurons more efficiently during development. Here, we investigated the tropism of LV in the degenerating retina of mice, knowing that the retina structure changes during degeneration. We postulated that the viral transduction would be increased by the alteration of the interphotoreceptor matrix (IPM). We tested two different LV-pseudotypes using the VSVG and the Mokola envelopes. Methods: Subretinal injections were performed in wild-type (C57/Bl6) and rhodopsin knockout (Rho-/-) mice. We injected LV-VSVG-EFS-GFPII into 3.3-4.9 month old mice and LV-VSVG-Rho-GFP into 1-1.4 month old mice to target the photoreceptors (PR). LV-MOK-CMV-GFP was injected into 2.4-3.3 months old mice. We sacrificed the animals one week post injection, used immunohistochemistry to identify the transduced cells, and investigated the OLM integrity. Results: Using LV-VSVG-EFS-GFPII into 3.3-4.9 months mice, we observed significant retinal and RPE transduction in Rho-/- mice. However, the retinas showed transduction mainly at the injection's site. We mostly observed GFP+ cells having a Müller cell morphology. Using LV-MOK-CMV-GFP into 2.4-3.3 months mice, we evidenced the same pattern of viral infection, but with more Müller cells targeted by the virus. Using LV-VSVG-Rho-GFP into 1-1.4 month old mice, we don't note any difference between Rho-/- and wild-type mice for transduced cells. The IPM stained with ZO1 appears irregular into the 4.9 months old Rho-/- mice; for the youngest mice (Rho-/- and C57/Bl6), there is no modification of the IPM. Conclusion: The degeneration improves retinal cells transduction due to the alteration of the IPM in old Rho-/- mice. Müller cells seem (by morphological evidences) to be the principal cells expressing the transgene. The LV with Mokola envelope can transduce Müller cells in a degenerating retina with an intact IPM. In 1 month old mice, the degeneration doesn't enhance the transduction in rod PR probably because the IPM is not yet altered. The possibility to target photoreceptors at a later stage of the degeneration is under investigation.

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The European genus Ophrys (Orchidaceae) is famous for its insect-like floral morphology, an adaptation for a pseudocopulatory pollination strategy involving Hymenoptera males. A large number of endemic Ophrys species have recently been described, especially within the Mediterranean Basin, which is one of the major species diversity hotspots. Subtle morphological variation and specific pollinator dependence are the two main perceptible criteria for describing numerous endemic taxa. However, the degree to which endemics differ genetically remains a challenging question. Additionally, knowledge regarding the factors underlying the emergence of such endemic entities is limited. To achieve new insights regarding speciation processes in Ophrys, we have investigated species boundaries in the Fly Orchid group (Ophrys insectifera sensu lato) by examining morphological, ecological and genetic evidence. Classically, authors have recognized one widespread taxon (O. insectifera) and two endemics (O. aymoninii from France and O. subinsectifera from Spain). Our research has identified clear morphological and ecological factors segregating among these taxa; however, genetic differences were more ambiguous. Insights from cpDNA sequencing and amplified fragment length polymorphisms genotyping indicated a recent diversification in the three extant Fly Orchid species, which may have been further obscured by active migration and admixture across the European continent. Our genetic results still indicate weak but noticeable phylogeographic clustering that partially correlates with the described species. Particularly, we report several isolated haplotypes and genetic clusters in central and southeastern Europe. With regard to the morphological, ecological and genetic aspects, we discuss the endemism status within the Fly Orchid group from evolutionary, taxonomical and conservation perspectives.

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Malignant gliomas are currently diagnosed based on morphological criteria and graded according to the World Health Organization classification of primary brain tumors. This algorithm of diagnosis and classification provides clinicians with an estimated prognosis of the natural course of the disease. It does not reflect the expected response to specific treatments beyond surgery (eg, radiotherapy or alkylating chemotherapy). Clinical experience has revealed that gliomas sharing similar histomorphological criteria might indeed have different clinical courses and exhibit highly heterogenous responses to treatments. This was very impressively demonstrated first for oligodendrogliomas. The presence or lack of combined deletions of the chromosomal segments 1p/19q was associated with different benefit from radiotherapy and chemotherapy. We review current molecular markers for malignant gliomas and discuss their current and future impact on clinical neuro-oncology.

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In otherwise successful gene therapy trials for the treatment of SCID patients and others, insertional mutagenesis has resulted in leukemia development. Besides the integration of vectors that including strong enhancers, more recently, SIN-vectors have been shown to partially retain oncogenic potential. The identification of genetic elements which would both prevent such activation effects and shield the transgene from silencing, is a main challenge. Previous attempts met with difficulties in producing the vectors and poor efficacy of the insulators (GIE). The improvement of integrating vectors safety has been investigated using new candidate synthetic GIEs. The latter have been introduced in retroviral and lentiviral vectors. Native LTRs, SIN-LTRs, and SIN-insulated constructs have been designed and compared, using two sets of internal promoter, i.e. strong and housekeeping. We could establish that a specific insulator translates at best into functional activity and boundary effect in both vector types. We could also determine that other genetic elements are key determinants in order to achieve accurate expression and viral titre, from these insulated vectors. A dramatic shift in the expression profile is observed in target cells, with a homogenous pattern including data on both cell-lines and primary HSCs from cord blood. The assessment of potential genotoxicity will be presented, based on the comparison of the integration patterns ingenuity in human target cells sampled over a three months period with both reference LTRs and SIN versus test insulated vectors, using high-throughput pyro-sequencing.

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Echocardiography is the preferred initial test to assess cardiac morphology and ventricular function. Cardiac MRI enables an optimal visualisation of heart muscle without contrast injection, and precise measurement of the ventricular volumes and systolic function. It is therefore an ideal test for patients with poor echocardiographic windows or for the specific evaluation of right heart chambers. Heart CT also remarkably images heart muscle and precisely measures ventricular systolic function after intravenous injection of iodinated contrast. Coronary CT may also, in selected cases, avoid the need for diagnostic coronary angiography. Although very accurate, these imaging modalities are expensive and may be contra-indicated for a particular patient. Their use in clinical practice has to follow the accepted guidelines.

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BACKGROUND: In our hands, in vivo segmental vessel length changes up to 5% because of blood pressure: increasing in arterial pressure is associated to decrease in segmental vessel length. METHODS AND MATERIAL: Using two piezoelectric crystals sutured on vessel wall and a high fidelity pressure probe, we recorded artery length variations as function of blood pressure, before and after an end-to-end anastomosis on four pigs carotid arteries. RESULTS: Mean arterial pressure before anastomosis = 73 mmHg (+/- 12); mean arterial pressure after anastomosis = 91 mmHg (+/- 14); mean crystals displacement before anastomosis during systole = -0.21 mm; mean crystals displacement after anastomosis during systole = +0.24 mm; mean distance between crystals before anastomosis = 12.3 mm (+/- 0.8) and after anastomosis = 11.2 mm (+/- 0.5). CONCLUSIONS: In the acute phase following an end-to-end anastomosis, an increase in blood pressure causes increasing in vessel length, with an exponential correlation. The anastomosis is constantly subjected to a longitudinal traction whose magnitude depends on blood pressure.