Guided bone regeneration with a synthetic biodegradable membrane: a comparative study in dogs

Objectives: The aim of the present study was to compare a newly developed biodegradable polylactide/polyglycolide/N‐methyl‐2‐pyrrolidone (PLGA/NMP) membrane with a standard resorbable collagen membrane (RCM) in combination with and without the use of a bone substitute material (deproteinized bovine bone mineral [DBBM]) looking at the proposed tenting effect and bone regeneration. Materials and methods: In five adult German sheepdogs, the mandibular premolars P2, P3, P4, and the molar M1 were bilaterally extracted creating two bony defects on each site. A total of 20 dental implants were inserted and allocated to four different treatment modalities within each dog: PLGA/NMP membrane only (Test 1), PLGA/NMP membrane with DBBM (Test 2), RCM only (negative control), and RCM with DBBM (positive control). A histomorphometric analysis was performed 12 weeks after implantation. For statistical analysis, a Friedman test and subsequently a Wilcoxon signed ranks test were applied. Results: In four out of five PLGA/NMP membrane‐treated defects, the membranes had broken into pieces without the support of DBBM. This led to a worse outcome than in the RCM group. In combination with DBBM, both membranes revealed similar amounts of area of bone regeneration and bone‐to‐implant contact without significant differences. On the level of the third implant thread, the PLGA/NMP membrane induced more horizontal bone formation beyond the graft than the RCM. Conclusion: The newly developed PLGA/NMP membrane performs equally well as the RCM when applied in combination with DBBM. Without bone substitute material, the PLGA/NMP membrane performed worse than the RCM in challenging defects, and therefore, a combination with a bone substitute material is recommended. To cite this article:
Jung RE, Kokovic V, Jurisic M, Yaman D, Subramani K, Weber FE. Guided bone regeneration with a synthetic biodegradable membrane: a comparative study in dogs.
Clin. Oral Impl. Res. 22 , 2011; 802–807
doi: 10.1111/j.1600‐0501.2010.02068.x     

Effect of TNF-α on Raji cells at different cellular levels estimated by various methods

Tumor necrosis factor (TNF)-α, a pleiotropic cytokine, has been shown to induce diverse and opposite effects on lymphoid malignancy depending on TNF receptor system expression. Based on this, we investigated its in vitro dose- and time-related effect on the malignant B-cell line Raji, derived from Burkitt lymphoma patients, at different intracellular levels. The membrane alteration was estimated by lactate dehydrogenase (LDH) release and by flow cytometry; intracellular metabolic energy by determination of the total intracellular LDH activity; total cytosole protein mass by sulforhodamine B assay; and cell growth by incorporation of [³H]thymidine into DNA. Significant increase of LDH through cell membrane alteration was accompanied by decrease of intracellular metabolized energy and total protein mass. TNF-α at lower concentrations (125 and 250 pg/ml) significantly induced cell proliferation in comparison with 1,000 pg/ml of TNF-α, which induced more cell death. TNF-α induced maximal apoptosis rate up to 30% after 24 h, showing more effects for a necrotic form of cell death. Here we reported opposite and diverse effects of TNF-α at different intracellular levels in Raji cells, when applied in different assays, showing characteristics for every cellular compartment.     

Nitroglycerine effects on portal vein mechanics and oxidative stress in portal hypertension

AIM:Тo examine the effects of nitroglycerine on portal vein haemodynamics and oxidative stress in patients with portal hypertension.METHODS:Thirty healthy controls and 39 patients with clinically verified portal hypertension and increasedvascular resistance participated in the study.Liver di-ameters,portal diameters and portal flow velocities were recorded using color flow imaging/pulsed Doppler detection.Cross-section area,portal flow and index of vascular resistance were calculated.In collected blood samples,superoxide anion radical (O 2-),hydrogen per-oxide (H 2 O 2),index of lipid peroxidation (measured as TBARS) and nitric oxide (NO) as a marker of endothelial response (measured as nitrite-NO 2-) were determined.Time-dependent analysis was performed at basal state and in 10th and 15th min after nitroglycerine (sublingual 0.5 mg) administration.RESULTS:Oxidative stress parameters changed sig-nificantly during the study.H 2 O 2 decreased at the end of study,probably via O 2-mediated disassembling in Haber Weiss and Fenton reaction;O 2-increased signifi-cantly probably due to increased diameter and tension and decreased shear rate level.Consequently O 2-and H 2 O 2 degradation products,like hydroxyl radical,initi-ated lipid peroxidation.Increased blood flow was to some extent lower in patients than in controls due to double paradoxes,flow velocity decreased,shear rate decreased significantly indicating non Newtonian char-acteristics of portal blood flow.CONCLUSION:This pilot study could be a starting point for further investigation and possible implemen-tation of some antioxidants in the treatment of portal hypertension.     

Correction to: Comparison of the 1-year clinical outcome of a novel cryoballoon to an established cryoballoon technology

Journal of Interventional Cardiac Electrophysiology -     

Rituximab for treatment of autoimmune hemolytic anemia

We report the successful use of rituximab as single treatment modality in a five-month-old boy with fulminant warm autoantibody autoimmune hemolytic anemia, resistant to standard treatment. On admission, laboratory tests showed a profound anemia with a hemoglobin of 2.6 g/dL. Indirect and direct antiglobulin tests were strongly positive, and nonspecific IgG autoantibodies were detected. Two days of intravenous corticosteroids (methylprednisolone 4mg/kg) and immunoglobulins (1g/kg) did not halt the hemolysis and the infant was severely transfusion-dependent. Rituximab 375mg/sq m weekly was given for 4 weeks, the hepatosplenomegaly gradually regressed, the lymphocytes normalized and he is free from hemolysis two years after treatment.     

Elevated TNF-alpha and LDH without parathormone disturbance is associated with diffuse osteolytic lesions in leukemic transformation of myelofibrosis

Myelofibrosis is a clonal myeloproliferative disorder characterized by splenomegaly, abnormal deposition of collagen in the bone marrow, extramedullary hematopoiesis, dacriocytosis, and leukoerythroblastic blood smear. Development and maintenance of fibrosis are mediated by a complex network of several cytokines, including tumor necrosis factor-alpha (TNF-alpha). Osteosclerosis is the most frequently observed bone change in myelofibrosis. Based on this, we present an atypical case of leukemic transformation in myelofibrosis associated with diffuse osteolytic lesions and extremely elevated TNF-alpha and lactate dehydrogenase (LDH). Parathormone was not disturbed.     

Interferon alpha sensitisation induced fatal renal insufficiency in a patient with chronic myeloid leukaemia: case report and review of literature

Renal dysfunction as a sequel to extended interferon alfa (IFNalpha) treatment in chronic myeloid leukaemia (CML) has been reported previously in six patients. An additional patient is presented with Philadelphia chromosome positive (Ph+) CML and nephrotic syndrome in whom initial renal insufficiency developed after only one month of low dose IFNalpha therapy. The renal biopsy showed a focal segmental mononuclear cell infiltration, basal membrane thickening, and deposits of immunoglobulins (IgG; IgAGM IC3). In spite of discontinuation of IFNalpha, renal function deteriorated and the patient died six months later. This case represents an instance of fatal kidney insufficiency as an untoward effect of sensitisation to the IFNalpha, confirmed by modified Coombs assay.