Model development for the viral Kcv potassium channel.

A computational model for the open state of the short viral Kcv potassium channel was created and tested based on homology modeling and extensive molecular-dynamics simulation in a membrane environment. Particular attention was paid to the structure of the highly flexible N-terminal region and to the protonation state of membrane-exposed lysine residues. Data from various experimental sources, NMR spectroscopy, and electrophysiology, as well as results from three-dimensional reference interaction site model integral equation theory were taken into account to select the most reasonable model among possible variants.

Cell survival within pulp and periodontal constructs.

The purpose of this study was to measure cell survival and degradation within tissue-engineered dental constructs. Dental pulp stem cells (DPSCs) and periodontal ligament stem cells (PLSCs) were seeded on three types of tissue engineering scaffolds: a synthetic open-cell D,D-L,L-polylactic acid (polymer) scaffold, a bovine collagen scaffold (collagen), and a calcium phosphate bioceramic (calcium phosphate) scaffold. The dental pulp and periodontal constructs (n = 144) were maintained in cell culture for between 3 and 14 days.

A prospective evaluation of the feasibility and utility of additional tools to obtain information from recently diagnosed HIV infected patients.

Question Under Study: Can additional information be obtained from recently HIV diagnosed individuals?

Methods: A 1-year prospective Swiss study, including all newly diagnosed HIV-infected patients. Information on circumstances of HIV infection was collected through physician- and patient questionnaires and patient interviews. Information on timing of infection was linked with an HIV-antibody avidity assay.

Unicameral bone cyst: a retrospective study of three surgical treatments.

Between 1979 and 2004, 167 patients younger than 20 years were treated surgically for humeral or femoral unicameral bone cysts with either injection of corticosteroids (steroids), curettage plus bone grafting (curettage), or a combination injection of steroids, demineralized bone matrix, and bone marrow aspirate (SDB) at Children's Hospital of Boston and Massachusetts General Hospital (mean followup, 7.3 years; range, 1 month-27 years). Outcomes included treatment failure (defined clinically as subsequent pathologic fracture or need for retreatment to prevent pathologic fracture) and complications.

Osteoblastoma: a 30-year study of 99 cases.

Background And Objectives: Osteoblastoma is a rare, bone-forming neoplasm accounting for 1% of primary bone tumors. It arises in young patients and develops in long bones and posterior elements of the spine. Osteoblastoma is characterized by interconnecting trabeculae of woven bone and rimmed by prominent osteoblasts.

Prognostic factors for patients with Ewing sarcoma (EWS) at first recurrence following multi-modality therapy: A report from the Children's Oncology Group.

Background: The prognosis for patients with recurrent Ewing sarcoma (EWS) is very poor with 5-year survival of 13%.

Methods: To evaluate prognostic factors for these patients we studied patients initially treated on the multi-institutional study INT0091.

Results: Two hundred sixty-two patients experienced disease recurrence.

Complications and risk factors for failure of rotationplasty: review of 25 patients.

Unlabelled: Rotationplasty is one treatment option for femoral bone sarcomas in skeletally immature patients. This procedure enables patients to avoid phantom pain, limb length discrepancy, or loosening of an endoprosthesis, and good functional outcome has been reported. However, rotationplasty is only rarely indicated and the surgical complications or risk factors for failure of the procedure that might influence choices of treatment or patient counseling have not been well described.

Orthopedic board certification and physician performance: an analysis of medical malpractice, hospital disciplinary action, and state medical board disciplinary action rates.

Specialty board certification status has become the de facto standard of competency by which the profession and the public recognize physician specialists. However, the relationship between orthopedic board certification and physician performance has not been established. Rates of medical malpractice claims, hospital disciplinary actions, and state medical board disciplinary actions were compared between 1309 board-certified (BC) and 154 non-board-certified (NBC) orthopedic surgeons in 3 states.

Burn plasma transfer induces burn edema in healthy rats.

Thermal injuries greater than 20% body surface area (BSA) result in systemic shock with generalized edema in addition to local tissue destruction. Burn shock is induced by a variety of mediators, mainly immunomodulative cytokines. This experimental study evaluates if burn shock can be induced in healthy rats by transfer of burn plasma (BP) with mediators.

Osteofibrous dysplasia and adamantinoma in children and adolescents: a clinicopathologic reappraisal.

Osteofibrous dysplasia (OFD) and adamantinoma are rare and most commonly arise in the tibia of young individuals. Although OFD has typical histopathologic features, areas resembling OFD have often been noted at the periphery of otherwise classic adamantinomas, and some have suggested that OFD may be either a precursor to or a regressive phase of adamantinoma. The so-called OFD-like adamantinoma encompasses some features of both OFD and adamantinoma.

Microfluidic photomechanic infrared receptors in a pyrophilous flat bug.

Infrared (IR) receptors are so far known only in boid and crotalid snakes and in three genera of pyrophilous beetles that seek out forest fires. Pyrophilous insects can also be found in other orders, however, so it can be hypothesised that IR receptors also occur in some of these species. We investigated the pyrophilous Australian flat bug Aradus albicornis and found a small number of dome-shaped sensilla (diameter 13 microm) on the prothorax, which have previously not been described.

Osteosarcoma: the addition of muramyl tripeptide to chemotherapy improves overall survival--a report from the Children's Oncology Group.

Purpose: To compare three-drug chemotherapy with cisplatin, doxorubicin, and methotrexate with four-drug chemotherapy with cisplatin, doxorubicin, methotrexate, and ifosfamide for the treatment of osteosarcoma. To determine whether the addition of muramyl tripeptide (MTP) to chemotherapy enhances event-free survival (EFS) and overall survival in newly diagnosed patients with osteosarcoma.

Patients And Methods: Six hundred sixty-two patients with osteosarcoma without clinically detectable metastatic disease and whose disease was considered resectable received one of four prospectively randomized treatments.

Detection and analysis of cancer genes amplified from bone material of a Scythian royal burial in Arzhan near Tuva, Siberia.

Molecular paleopathology has become an emerging field that helps to characterize molecular markers of past disease. Especially highly sensitive genetic techniques such as PCR are an important means of unraveling changes in ancient DNA extracted from bone tissue, teeth and mummified soft tissue. In the present study, excavated bone material from the skeleton of a Scythian sovereign, morphologically and immunohistochemically suspicious of a metastatic prostate carcinoma, was analyzed by PCR for amplifiable human gene sequences.

Assessment of recent HIV-1 infection by a line immunoassay for HIV-1/2 confirmation.

Background: Knowledge of the number of recent HIV infections is important for epidemiologic surveillance. Over the past decade approaches have been developed to estimate this number by testing HIV-seropositive specimens with assays that discriminate the lower concentration and avidity of HIV antibodies in early infection. We have investigated whether this "recency" information can also be gained from an HIV confirmatory assay.

Perspectives on health disparities in orthopaedic oncology.

A few studies indicate that race- and culture-related differences exist among patients with bone tumors. However, there is little information regarding sarcomas. Existing studies indicate that, in the United States, race and cultural background may not significantly affect the survival rate of patients with sarcoma.

Improving diversity in orthopaedic residency programs.

Achieving a balanced diversity in orthopaedic residency programs is a critical component in improving the quality of orthopaedic care delivered to all patients. Compared with the demographics of medical school classes, women are notably underrepresented in orthopaedic residency programs, and racial and ethnic minority groups are unevenly represented. Diversifying residency programs positively affects all residents and their ability to deliver care and create positive physician-patient relationships.

Are fibula strut allografts a reliable alternative for periarticular reconstruction after curettage for bone tumors?

Bone tumors occurring in periarticular locations may cause a substantial risk of subchondral fracture and collapse. Poly-methylmethacrylate has been used for reconstruction in these instances because of its immediate structural stability. Allogeneic graft allows for biologic incorporation and remodeling, but it takes longer.

The role of the nurse academician in promoting evidence-based practice in a brain injury rehabilitation unit.

There are many rehabilitation teams and rehabilitation consultants. The team presented here involved the unique collaboration of university nursing scholars and clinicians from a local rehabilitation hospital. The melding of these two groups is providing new opportunities for staff nurses, administrators, and faculty members to work together and use nursing research to provide the base of evidence necessary to enhance rehabilitation nursing knowledge in the brain injury setting.

Treatment of metastatic Ewing sarcoma/primitive neuroectodermal tumor of bone: evaluation of increasing the dose intensity of chemotherapy--a report from the Children's Oncology Group.

Background: The outcome for patients with Ewing sarcoma family of tumors (ESFTs) of bone with metastases at diagnosis remains poor despite new approaches to treatment. We evaluated whether a dose-intensity chemotherapy regimen improved survival for patients with ESFTs of bone with metastases at diagnosis.

Methods: We entered 60 patients with metastatic ESFTs of bone onto a single arm trial of a new intensive therapy.

Novel karyotypes in giant cell-rich lesions of bone.

Giant cell-rich lesions of bone, including giant cell tumor of bone, giant cell reparative granuloma (GCRG), and aneurysmal bone cyst (ABC), may have overlapping clinical, radiologic, and histopathologic features. In fact, GCRG and solid ABC are currently differentiated solely based on skeletal location. Prior cytogenetic studies have reported that telomeric associations are present in the majority of giant cell tumors of bone, whereas translocations involving 16q22 and/or 17p13 are characteristic of ABCs.

Electrophysiological characterisation of the infrared organ of the Australian "Little Ash Beetle" Acanthocnemus nigricans (Coleoptera, Acanthocnemidae).

This study characterises the response properties of the sensilla located on the prothoracic disc organ of the beetle Acanthocnemus nigricans, such as intensity response functions and temporal coding properties. Warming the sensilla by a red laser accelerated their ongoing spiking activity, cessation of the stimulus suppressed their firing as revealed by extracellular recordings. Convective heat sources also increased sensillum activity, but stimuli of other modalities failed to elicit responses.

Imaging of pseudoneoplastic masses associated with allografts.

Objective: The objective of this study is to describe the imaging features of non-neoplastic masses suspected of being tumor recurrences adjacent to allografts. The allografts were utilized for the treatment of various musculoskeletal tumors.

Materials And Methods: We reviewed the medical records and imaging studies of 56 patients who were suspected of having recurrent tumors following surgical resection and allograft replacement treatment for a variety of musculoskeletal neoplasms.

Radiation therapy for control of soft-tissue sarcomas resected with positive margins.

Purpose: Positive margins (PM) remain after surgery in some soft-tissue sarcoma (STS) patients. We investigated the efficacy of radiation therapy (RT) in STS patients with PM.

Methods And Materials: A retrospective chart review was performed on 154 patients with STS at various anatomic sites with PM, defined as tumor on ink, who underwent RT with curative intent between 1970 and 2001.

Vinblastine and methotrexate for desmoid fibromatosis in children: results of a Pediatric Oncology Group Phase II Trial.

Purpose: To determine the efficacy and safety of using vinblastine (Vbl) and methotrexate (Mtx) in children with desmoid-type fibromatosis that is recurrent or not amenable to treatment with radiation or surgery.

Patients And Methods: A phase II study was conducted within the Pediatric Oncology Group. Patients were treated using Vbl (5 mg/m2/dose) and Mtx (30 mg/m2/dose), both administered by intravenous injection weekly for 26 weeks and every other week for an additional 26 weeks.