Finite element simulations of the effects of an extraoral device,RAMPA, on anterosuperior protraction of the maxilla and comparison with gHu-1 intraoral device

ObjectivesTo investigate the effects of an extraoral device, right-angle maxillary protraction appliance (RAMPA), combined with a semi-rapid maxillary expansion intraoral device (gHu-1) on the anterosuperior protraction of maxillary bone.Materials and MethodsThe finite element (FE) model included craniofacial bones and all sutures. The linear assumption was assumed for the FE simulations and the material properties of bones and sutures. The gHu-1 was simulated under screw activations equal to Δx = 0.25 and 0.5 mm in the lateral direction with and without RAMPA under a set of external forces {F₁ = 2.94, F₂ = 1.47, F₃ = 4.44} N.ResultsDisplacement contours, nodal displacements of 12 landmarks, and von Mises stresses were compared. Combining RAMPA and gHu-1 (with Δx = 0.25 mm) resulted in changes in the displacement of the front part of the maxilla near the mid-palatal suture from (0.02, −0.1, −0.02) mm to (0.02, 0.3, 0.8) mm. For gHu-1 with Δx = 0.5 mm, the displacement of the same part changed from (0.04, −0.04, −0.2) mm to (0.04, 0.3, 0) mm. Similar trends were found in other locations.ConclusionsThe findings are in agreement with the previous cephalometric clinical data of an 8-year-old patient and prove the positive effects of RAMPA on the anterosuperior protraction of the maxilla when it is combined with the intraoral device gHu-1. In addition, RAMPA does not interfere with the lateral expansion generated by the intraoral device.     

Proinflammatory Cytokine Gene Polymorphisms in Irritable Bowel Syndrome

Introduction

Irritable bowel syndrome (IBS) is a multifactorial functional gastrointestinal disorder, characterized by recurrent abdominal pain and altered bowel habits. Proinflammatory cytokines can play an important role in intestinal inflammation, while their production is under genetic control.

Methods

This study was performed in a group of patients with IBS to analyze the genotype frequencies of a number polymorphic genes coding for proinflammatory cytokine (interleukin-6 (IL), tumor necrosis factor-alpha (TNF-α), and IL-1 group). Using polymerase chain reaction with sequence-specific primers method, the cytokine genes were amplified, and alleles and genotypes of 71 patients with IBS were detected on gel electrophoresis, and the results were compared with healthy control subjects.

Results

Results of the analyzed data showed that the frequencies IL-1R C allele at position Pst-I 1970 (P?=?0.017), IL-6 G allele at position ?174 (P?=?0.002), and TNF-α G allele at position ?238 (P?<?0.001) in the patient group were significantly higher than the control group. IL-6 GG genotype (?174) and TNF-α GG genotype (?238) in the patient group were also significantly overrepresented (P?<?0.001), while IL-6 CG genotype (?174) and TNF-α GA genotype (?238) were significantly decreased in the patients with IBS (P?<?0.001). The frequencies of IL-6 (?174, nt565) GG haplotype and TNF-α (?308, ?238) GG haplotype were also significantly higher in the patient group (P?<?0.001), whereas the frequencies of the haplotypes IL-6 CG and TNF-α GA were significantly decreased in the patients with IBS (P?<?0.001).

Conclusion

IL-6 and TNF-alpha proinflammatory cytokine gene polymorphisms could change individual susceptibility to IBS and might have a role in pathophysiology of disease.     

Correlation Between Inducible Nitric Oxide Synthase and Cyclooxygenase-2 Expression in Human Colorectal Adenocarcinoma: A Cross-Sectional Study

Cyclooxygenase-2 (COX-2) enzyme is believed to play a role in tumor angiogenesis, differentiation, and apoptosis. The inducible isoform of nitric oxide synthase (iNOS) also has the potential ability to damage DNA and conceivably contribute to tumor formation by a rise in nitric oxide production. Seventeen patients diagnosed with colorectal adenocarcinoma, who underwent surgical resection of the tumor, were enrolled in the study. Two macroscopic tissue samples, one from the tumor and the other from the tumor free surgical margin were collected from every patient as formalin fixed paraffin embedded blocks. Samples were analyzed for iNOS and COX-2 expression by immunohistochemistry and Western blotting. Results were digitized and semi-quantitatively analyzed. Immunohistochemistry revealed a similar pattern of expression for both iNOS and COX-2, as both were detected in tumor and epithelial cells. The mean iNOS and COX-2 levels determined by Western blotting method were significantly higher in tumor than in the tumor-free tissues (Wilcoxon signed-rank test, p < 0.001 both for iNOS and COX-2). Patients with lymph node involvement had higher levels of both enzymes in tumors (Mann-Whitney U test, p < 0.05). There was correlation between iNOS and COX-2 expression of tumor determined by immunohistochemistry and also by Western blotting (Spearman’s rho test, R = 0.53, p = 0.03 and R = 0.57, p = 0.02, respectively). In conclusion, our results point out a relationship between iNOS and COX-2 expression in human colorectal adenocarcinomas and may also suggest a possible link between advanced stages of the disease and higher expression of iNOS and COX-2.     

Selective Internal Radiation Therapy with Yttrium-90 for Intrahepatic Cholangiocarcinoma: A Systematic Review on Post-Treatment Dosimetry and Concomitant Chemotherapy

Selective internal radiation therapy (SIRT) with yttrium-90 (⁹⁰Y)-loaded microspheres is increasingly used for the treatment of Intrahepatic Cholangiocarcinoma (ICC). Dosimetry verifications post-treatment are required for a valid assessment of any dose-response relationship. We performed a systematic review of the literature to determine how often clinics conducted post-treatment dosimetry verification to measure the actual radiation doses delivered to the tumor and to the normal liver in patients who underwent SIRT for ICC, and also to explore the corresponding dose-response relationship. We also investigated other factors that potentially affect treatment outcomes, including the type of microspheres used and concomitant chemotherapy. Out of the final 47 studies that entered our study, only four papers included post-treatment dosimetry studies after SIRT to quantitatively assess the radiation doses delivered. No study showed that one microsphere type provided a benefit over another, one study demonstrated better imaging-based response rates associated with the use of glass-based TheraSpheres, and two studies found similar toxicity profiles for different types of microspheres. Gemcitabine and cisplatin were the most common chemotherapeutic drugs for concomitant administration with SIRT. Future studies of SIRT for ICC should include dosimetry to optimize treatment planning and post-treatment radiation dosage measurements in order to reliably predict patient responses and liver toxicity.     

Eleven-Year Retrospective Report of Super-Selective Venous Sampling for the Evaluation of Recurrent or Persistent Hyperparathyroidism in 32 Patients

CardioVascular and Interventional Radiology - Parathyroid venous sampling (PAVS) is usually reserved for patients with persistent or recurrent hyperparathyroidism after parathyroidectomy with...     

Staged stenting of a long aneurysm of a saphenous vein coronary artery bypass graft

A 65-year-old male who underwent coronary artery bypass graft surgery (CABG) 21 years ago and received a mitral valve annuloplasty 5 years ago presented with recurrent angina. Computed tomography showed an aneurysm of the saphenous vein graft (SVG), measuring approximately 43 x 33 mm with mural thrombus. Diagnostic catheterization showed that the SVG to the marginal branch of the left circumflex artery had a large aneurysm with mural thrombus, which measured 32 x 45 mm. The lesion was pretreated with a 5.5 x 47 mm Magic Wallstent (Boston Scientific, Maple Grove, Minnesota) followed by 4.0 x 26, 4. x 26, 4.0 x 19 and 4.0 x 16 mm PTFE-covered stents. Postdilatation was performed using a 5.0 x 20 mm balloon. Because of significant flow from the distal end of the PTFE-covered stents seen at coronary angiography after 6 months, we implanted another 4.0 x 26 mm PTFE-covered stent at the distal edge of the previous stent. Final angiography and intravascular ultrasound showed no significant flow into the aneurysm.     

Precordial low voltage in patients with ascites.

AIMS: Electrocardiographic (ECG) changes in patients with ascites are not well studied. The aim of this study was to evaluate ECG changes in patients with ascites. METHODS AND RESULTS: Prospective analysis of patients with ascites who were referred for paracentesis. Three ECGs were recorded before paracentesis. ECG 1 was a standard 12-lead ECG. For ECG 2 the precordial leads were placed 1 intercostal space (ICS) and for ECG 3, 2 ICS cranially. The sums (Sigma) of the QRS in ECG1 were compared with ECG 2 and 3. In six patients the same ECG protocol was performed after removal of ascites. Ten hospitalized patients without ascites served as controls. Twenty patients with ascites were analysed. Limbs leads low voltage was present in 11 patients and precordial low voltage in four patients. Cranial placement of the precordial electrodes increased SigmaQRS in all patients with ascites. The most prominent voltage changes appeared in the leads V4-V6 (+62%). Paracentesis of ascites normalized precordial leads low-voltage, while limbs leads low voltage remained. Cranial placement of the precordial electrodes in patients without ascites decreases SigmaV1-V6. CONCLUSION: We describe a phenomenon of precordial voltage changes in patients with ascites, not reported in the literature yet. By placing the precordial electrodes 1 and 2 ICS cranially the voltage changes can be 'corrected' and this should be done in all patients prior to further diagnostic workup. Removal of the ascites normalizes the precordial leads low voltage.     

Absence of donor-derived keratinocyte stem cells in skin tissues cultured from patients after mobilized peripheral blood hematopoietic stem cell transplantation

OBJECTIVE: Recent studies suggest that primitive bone marrow-derived cells contribute to regeneration of many tissues, including muscle, endothelium, myocardium, neural tissues, liver, and skin. Conversely, primitive cells resident in muscle and other tissues have been reported to reconstitute hematopoiesis. We investigated the contribution of cells with a primitive hematopoietic phenotype to human epidermal skin formation in recipients of allogeneic mobilized peripheral blood hematopoietic stem cell (HSC) transplantation. PATIENTS AND METHODS: Our study population included female patients who had received granulocyte colony-stimulating factor mobilized peripheral blood HSC transplants from male donors for a variety of benign and malignant hematologic disorders at least 6 months before study entry, with a history of skin graft-vs-host disease. Epidermal skin cells (keratinocytes) obtained from punch biopsies of the skin were cultured under conditions specific for growth and expansion of homogenous populations of keratinocytes from keratinocyte stem cells. After multiple passages, DNA was extracted from cultured cells and evaluated by two different polymerase chain reaction (PCR) method for detection of Y chromosome specific sequences. RESULTS: Neither sensitive PCR-based technique revealed the presence of male donor-derived keratinocyte stem cells in keratinocytes cultured from skin biopsies of female allogeneic transplantation recipients. CONCLUSIONS: We could not confirm the contribution of donor mobilized peripheral blood hematopoietic stem cells to keratinocyte stem cell populations after HSC transplantation. These results cannot explain the presence of donor-derived cells with keratinocyte phenotypic markers in tissue sections of HSC transplant recipients.