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991.

Background  

Breast augmentation was performed on nine female volunteer patients to determine the influence of three textured surfaces on fibrous capsule formation. The high degree of surface texture reduced the capsular fibrous tissue formation.  相似文献   
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The purpose of this study is to report the clinical and radiographic outcomes after open reduction and internal fixation of displaced proximal humerus fractures with the “Da Vinci System®”. It is a triangle-shaped cage whose opposite faces are pierced, and it represents the evolution of a triangle-shaped bone block technique performed in a previous series of 33 patients. The new device is an interesting innovation to treat the difficult problem of fracture fragments reconstruction and stability, metaphyseal bone loss and proximal humerus revascularization. According to the technique, authors position the correct size titanium cage into the metaepiphysis, so that the fragments are reduced upon the cage, and they are stabilized with a minimal osteosynthesis by Kirschner wires, titanium screws or transosseous sutures. If the fracture line involves the proximal portion of the diaphysis, it is possible to use a short low profile plate. Between May 2005 and November 2009, we treated 71 patients (34 men and 37 women), even though we included in our study only 59 patients, who had a minimum follow-up of 12 months. The first patient has been treated in May 2005 and the last one in September 2008. The mean age was 60.8 years (minimum 27, maximum 78). There were 8 displaced 3-part fractures, 20 displaced 4-part fractures, 10 4-part fracture-dislocations, 5 head splitting, 12 unclassified multifragmentary fractures, 1 2-part fracture with multifragmentary calcar and 3 malunions of 4-part fracture. The functional results were evaluated by the Constant score. With a mean follow-up of 24 months (minimum 12, maximum 36 months), the mean Constant score was 80.25. The results were excellent or good in 48 cases, bad in 2 cases and satisfactory in 9; the mean active anterior elevation (AAE) was 160°. All fractures but one healed; in one case, we had a deep infection after 80 days since the operation, treated with a preformed cement spacer.  相似文献   
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A selective involvement of protein kinase C-zeta (PKC-zeta) in the events regulating cell proliferation has been recently proposed. Here we report a flow cytometric method allowing the simultaneous association of intracellular PKC-zeta expression or phosphorylation with each cell cycle phase. Current methods for flow cytometry analysis were applied to several cell lines and compared to the method developed in our laboratory. The latter includes 2% paraformaldehyde (PFA), as fixing agent, a permeabilization/saturation step by means of a solution containing 150 mM NaCl, 5 mM EDTA, 50 mM Tris-HCl pH 7.4, 0.05% NP-40, 0.25% lambda-carrageenan and 0.02% NaN3, followed by labelling with a primary antibody (PKC-zeta or P-PKC-zeta) and with the appropriate FITC-conjugated secondary antibody. Cells processed by such a method disclosed no substantial modification of light scattering features with respect to live cells. In addition, stainability with anti-PKC-zeta or anti-P-PKC-zeta antibodies was well preserved while stoichiometric staining of DNA with PI enabled accurate cell cycle analysis. Results show that a distinct up-regulation of P-PKC-zeta in G2/M phase occurs. The method here described, therefore, represents a simple, reproducible and conservative assay for a simultaneous assessment of intracellular PKC or P-PKC modulations within each cell cycle phase.  相似文献   
996.
The systemic induction of cytokines and prostaglandins plays a key role in the development of fever. However, whether fever is triggered by local injection of lipopolysaccharide (LPS) and the involvement of locally produced prostaglandins in periodontal tissue has never been assessed. Thus, we tested the hypothesis that the trigeminal nerve is a neuronal pathway that signals the brain during acute periodontitis, and this response involves prostaglandin induction. Rats were given a gingival intra-pouch injection of sterile saline or Escherichia coli lipopolysaccharide, at doses of 10 and 100 μg/kg. Some animals were pre-treated with the local anesthetic mepivacaine or had the peripheral branches of the trigeminal nerves transected. Another group of animals were pre-treated (locally or systemically) with the nonselective inhibitor of cyclooxygenases diclofenac. Body core temperature (T b) was measured by means of biotelemetry before and after injections. LPS elicited a dose-dependent increase in T b, which was abolished by mepivacaine, bilateral transection of the peripheral branches of the trigeminal nerve, or local treatment with diclofenac. The results indicate that there is an activation of periodontal nerves to induce fever by LPS. It also shows that local formation of prostaglandins plays a role in fever development. Moreover, immunohistochemistry detected c-fos expression in the subnucleus caudalis of spinal trigeminal nucleus and in the preoptic area of the hypothalamus 2 and 3 h after LPS injection, further confirming the role of trigeminal nerve signaling brain in acute periodontitis.  相似文献   
997.
Richter syndrome (RS) represents the transformation of chronic lymphocytic leukemia to aggressive lymphoma. We explored intraclonal diversification (ID) of immunoglobulin genes in order to (i) follow the evolutionary history of the RS clone (ii) compare the role of ID in clonally related RS vs. clonally unrelated cases. Most (10/11, 90.9%) clonally related RS stem from the predominant clone observed at CLL diagnosis. One single RS had a transformation pattern compatible with sequential evolution from a secondary CLL subclone. Once RS transformation had occurred, all secondary CLL subclones disappeared and were substituted by the dominant RS clone with its own descendants. These observations suggest that genetic lesions associated with RS transformation are acquired by a cell belonging to the original CLL clone, rather than being progressively accumulated by later CLL subclones. Accordingly, most (9/11, 81.1%) clonally related RS harbored a genetic lesion disrupting TP53 that was already present, though at subclonal levels, in 5/11 (45.5%) samples of the paired CLL phase. A fraction of clonally related RS switched off ID (4/11, 36.4%) or reduced the levels of ID (5/11, 45.4%) at transformation. Conversely, all clonally unrelated RS harbored ID and were characterized by a significantly higher mutation frequency compared to clonally related RS (median: 1.18 × 10(-3) vs. 0.13 × 10(-3); p =0.002). These data indicate that (i) clonally related RS stems from a cell that is already present within the initial CLL clone and (ii) clonally unrelated and clonally related RS are biologically distinct disorders also in terms of antigen affinity maturation.  相似文献   
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Currently, there is increasing interest in the in vivo protective effects of natural antioxidants found in dietary plants against oxidative damage caused by free radical species. Oxidative stress has been invoked as a causative agent in cancer and epidemiological data suggest that the consumption of fruits and vegetables may be associated with a lower incidence of cancer. The fruit of the Olea europaea L. and olive oil contain hundreds of phytochemicals and its extracts have recently been shown to exhibit antioxidant properties, due to the action of oleuropein. In view of these considerations, in this study, we investigated the effects of oleuropein on LNCaP and DU145 prostate cancer cell lines and on BPH-1 non-malignant cells. Oleuropein reduces cell viability and induces thiol group modifications, γ-glutamylcysteine synthetase, reactive oxygen species, pAkt and heme oxygenase-1. Exposing cell cultures to oleuropein induces an antioxidant effect on BPH-1 cells and a pro-oxidant effect on cancer cells. Our results confirm the beneficial properties of olive oil and oleuropein, suggesting its possible use as an adjuvant agent in the treatment of prostatitis, in order to prevent the transformation of hypertrophic to cancerous cells.  相似文献   
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