Premolar Root Changes Following Treatment with the Banded Herbst Appliance

AIM: The aim of this prospective study was to radiographically assess root morphology changes in maxillary and mandibular premolars following Herbst appliance treatment. PATIENTS AND METHODS: Twenty-five consecutive adolescents (19 boys and six girls, mean age 13.08 years) with Class II, Division 1 malocclusion were treated with the banded Herbst appliance for a mean period of 13.16 months. Periapical radiographs of the upper and lower premolars were obtained before appliance insertion and immediately after appliance removal using the parallel technique. All radiographs were scanned, digitized and analyzed using appropriately adjusted cephalometric software. The pre- and post-treatment length and area of the first and second maxillary and mandibular premolar roots were calculated. Statistical analysis included paired t-tests to evaluate pre- and posttreatment changes, and independent t-tests to compare the pre and post-treatment differences between the first and the second premolars, which served as controls. The level of significance was set at p 相似文献   

Abrogating chemotherapy-induced myelosuppression by recombinant granulocyte-macrophage colony-stimulating factor in patients with sarcoma: protection at the progenitor cell level.

PURPOSE: The purpose of this study was to optimize the dose, schedule, and timing of recombinant granulocyte-macrophage colony-stimulating factor (GM-CSF) administration that would best abrogate myelosuppression in patients with sarcoma. PATIENTS AND METHODS: Sarcoma patients who had experienced severe myelosuppression after chemotherapy with Cytoxan (cyclophosphamide; Bristol-Myers Squibb Co, Evansville, IN), Adriamycin (doxorubicin; Adria Laboratories, Columbus, OH), and dacarbazine ([CyADIC], cycle 1) were eligible. GM-CSF was administered during a 14-day period until 1 week before cycle 2 of CyADIC and was resumed 2 days after cycle 2 completion. The schedule subsequently was modified to allow the earlier administration of GM-CSF in which CyADIC was compressed from 5 days to 3 days, and GM-CSF was administered immediately after the discontinuation of CyADIC in cycle 2. To understand better the impact of GM-CSF on bone marrow stem cells, the proliferative status of bone marrow progenitors was examined during treatment. To evaluate the effects of GM-CSF on effector cells, select functions of mature myeloid cells were also examined. RESULTS: In the seven patients who were treated on the initial schedule, GM-CSF enhanced the rate of neutrophil recovery; however, severe neutropenia was not abrogated, By using the modified schedule in 17 patients, GM-CSF significantly reduced both the degree and the duration of neutropenia and myeloid (neutrophils, eosinophils, and monocytes) leukopenia. The mean neutrophil and mature myeloid nadir counts were 100/mm3 and 280/mm3 in cycle 1 and 290/mm3 and 1,540/mm3 in cycle 2 (P less than .01 and P less than .001). The duration of severe neutropenia (neutrophil count less than 500/mm3) and myeloid leukopenia (myeloid leukocyte count less than 1,000/mm3) were reduced from 6.2 and 6.8 days in cycle 1 to 2.8 and 1.4 days in cycle 2 (P less than .001). While 16 of 17 patients experienced severe myeloid leukopenia (less than 500/mm3) in cycle 1, only two of 17 experienced severe myeloid leukopenia in cycle 2 (P less than .001). Overall, severe neutropenia was abrogated in seven patients, which made them eligible for dose-escalation of Adriamycin. The fraction of cycling progenitors increased threefold on GM-CSF and decreased dramatically below the baseline within 1 day of GM-CSF discontinuation. CONCLUSIONS: The modified schedule improved the beneficial effects of GM-CSF by enhancing myeloprotection and permitting dose-intensification of chemotherapy. The increased myeloid mass and quiescent progenitors at the initiation of chemotherapy suggest that GM-CSF might allow further chemotherapy dose-rate intensification by shortening the interval between courses.     

In vitro strain distribution in the proximal tibia. Effect of varus-valgus loading in the normal and osteoarthritic knee

Six human cadaver legs were tested with strain-gauge rosettes to determine the effects of varus/valgus loading on the distribution of strain on the cortical bone of the proximal tibia at loads of up to 250 kg. Changes in the femorotibial angle of 1.5 degrees and 3.1 degrees, to create varus/valgus deformities, produced significant unloading of the opposite aspect of the normal leg. A varus deformity of 3.1 degrees in the medial compartment osteoarthritic model virtually unloaded the lateral compartment and, because of the bending effect, placed the whole of the lateral aspect of the leg into axial tension. Under these conditions, the axial strains in almost the whole of the medial aspect of the tibia were doubled, from an initial value of 250 microstrain (compressive) to a value of approximately 500 microstrain (compressive). While a change in load-action, to simulate a 3.1 degrees valgus deformity in the medial compartment osteoarthritic model, did not completely unload the medial plateau of the tibia, it was suggested that such unloading could be achieved with slightly greater valgus loading. Successful clinical results, employing valgus osteotomies in patients with medial compartment osteoarthritis, are obtained by unloading the medial compartment while markedly increasing compressive loads on the whole of the lateral aspect of the leg.     

Testicular torsion–detorsion and potential therapeutic treatments: A possible role for ischemic postconditioning

Testicular torsion is a common urological emergency among adolescent boys and young men. Rotation of the testis and twisting of the spermatic cord rapidly leads to ischemia, resulting in a loss of germ cells. Thus, prompt diagnosis and urgent surgical intervention are required, but the subsequent release of the torsion induces reperfusion injury, which causes further damage to the ischemic testis. Testicular torsion–detorsion (ischemia–reperfusion) injury triggers the generation of reactive oxygen species, pro‐inflammatory cytokines, neutrophil recruitment, lipid peroxidation, anoxia and apoptosis, which carry a significant risk of subsequent infertility. Previously, the effects of numerous pharmacological agents and treatments have been evaluated to prevent testicular ischemia–reperfusion injury in animal models. We propose a new treatment, especially postconditioning, to prevent adverse effects of ischemia–reperfusion injury after testicular torsion–detorsion.     

High miR-96 levels in colorectal adenocarcinoma predict poor prognosis,particularly in patients without distant metastasis at the time of initial diagnosis

Tumor Biology - MicroRNA-96 (miR-96) is an oncomiR that facilitates the development of malignant tumors by promoting growth, proliferation, and survival of cancer cells. Previous studies using...