Publications by authors named "William Ensminger"

Purpose: To compare knot and loop characteristics of commonly used high-strength tapes and high-strength round sutures.

Methods: Twenty tied 30-mm loops were prepared for using suture-knot combinations of 4 common arthroscopic knots or a hand-tied surgeon's knot and 7 sutures. Two tapes (BroadBand, SutureTape) and three no.

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Aims: Poly(methyl methacrylate) (PMMA)-based bone cements are the industry standard in orthopaedics. PMMA cement has inherent disadvantages, which has led to the development and evaluation of a novel silorane-based biomaterial (SBB) for use as an orthopaedic cement. In this study we test both elution and mechanical properties of both PMMA and SBB, with and without antibiotic loading.

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Case: A 69-year-old woman presented with a painful mass at her first metatarsophalangeal joint. Further evaluation was concerning for a neoplastic process, leading to surgical intervention. Pathological examination demonstrated hemosiderotic synovitis, and hematologic evaluation led to a new diagnosis of von Willebrand disease.

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Objectives: We have previously shown that refractory neuroendocrine tumors can respond to moderate doses of chemoradiotherapy. We completed a dose-escalation phase I/II trial combining hepatic arterial (HA) chemotherapy, chemoembolization, and dose-escalated whole liver radiotherapy to determine the maximum safe dose of radiation that could be delivered and to make a preliminary assessment of response.

Materials And Methods: From 2002 to 2009, 19 patients with symptomatic neuroendocrine liver metastases who failed somatostatin analog therapy were enrolled.

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Hepatobiliary cancers include a spectrum of invasive carcinomas arising in the liver (hepatocellular carcinoma), gall bladder, and bile ducts (cholangiocarcinomas). Gallbladder cancer and cholangiocarcinomas are collectively known as biliary tract cancers. Gallbladder cancer is the most common and aggressive type of all the biliary tract cancers.

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Transarterial radioembolization (TARE) with (90)Y microspheres delivers low dose rate radiation (LDR) to intrahepatic tumors. In the current study, we examined clonogenic survival, DNA damage, and cell cycle distribution in hepatocellular carcinoma (HCC) cell lines treated with LDR in combination with varying doses and schedules of 5-fluorouracil (5-FU), gemcitabine, and sorafenib. Radiosensitization was seen with 1 to 3 μM 5-FU (enhancement ratio 2.

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Poly(amidoamine) (PAMAM) dendrimers are branched water-soluble polymers defined by consecutive generation numbers (Gn) indicating a parallel increase in size, molecular weight, and number of surface groups available for conjugation of bioactive agents. In this article, we compare the biodistribution of N-acetylgalactosamine (NAcGal)-targeted [(14) C]1 -G5-(NH2 )5 -(Ac)108 -(NAcGal)14 particles to non-targeted [(14) C]1 -G5-(NH2 )127 and PEGylated [(14) C]1 -G5-(NH2 )44 -(Ac)73 -(PEG)10 particles in a mouse hepatic cancer model. Results show that both NAcGal-targeted and non-targeted particles are rapidly cleared from the systemic circulation with high distribution to the liver.

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Purpose: Radiation-induced gastric bleeding has been poorly understood. In this study, we described dosimetric predictors for gastric bleeding after fractionated radiation therapy.

Methods And Materials: The records of 139 sequential patients treated with 3-dimensional conformal radiation therapy (3D-CRT) for intrahepatic malignancies were reviewed.

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Purpose: Diffuse intrahepatic tumors are difficult to control. Whole-liver radiotherapy has been limited by toxicity, most notably radiation-induced liver disease. Amifostine is a prodrug free-radical scavenger that selectively protects normal tissues and, in a preclinical model of intrahepatic cancer, systemic amifostine reduced normal liver radiation damage without compromising tumor effect.

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There is an urgent need for novel polymeric carriers that can selectively deliver a large dose of chemotherapeutic agents into hepatic cancer cells to achieve high therapeutic activity with minimal systemic side effects. PAMAM dendrimers are characterized by a unique branching architecture and a large number of chemical surface groups suitable for coupling of chemotherapeutic agents. In this article, we report the coupling of N-acetylgalactosamine (NAcGal) to generation 5 (G5) of poly(amidoamine) (PAMAM-NH₂) dendrimers via peptide and thiourea linkages to prepare NAcGal-targeted carriers used for targeted delivery of chemotherapeutic agents into hepatic cancer cells.

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Purpose: Pancreatic neuroendocrine tumors (PNTs) are rare malignant neoplasms considered to be resistant to radiotherapy (RT), although data on efficacy are scarce. We reviewed our institutional experience to further delineate the role of RT for patients with PNTs.

Methods And Materials: Between 1986 and 2006, 36 patients with PNTs were treated with RT to 49 sites.

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Antiangiogenic therapy improves survival in patients with advanced stage cancers. Currently, there are no reliable predictors or markers for tumor vessel response to antiangiogenic therapy. To model effective antiangiogenic therapy, we disrupted the VEGF gene in three representative cancer cell lines.

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Purpose: A phase II trial was conducted to determine if high-dose radiation with concurrent hepatic arterial floxuridine would improve survival in patients with unresectable intrahepatic malignancies.

Patients And Methods: Three-dimensional conformal high-dose radiation therapy was delivered concurrently with hepatic arterial floxuridine in 128 patients. The radiation dose was based on a normal-tissue complication probability model and subjected the patient to an estimated maximum risk of radiation-induced liver disease of 10% to 15%.

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Previous work has shown that in humans the dose-limiting toxicity for fluorodeoxyuridine [2-fluoro-5'-deoxyuridine (FdUrd)] when administered by hepatic arterial infusion is biliary sclerosis. The current study was undertaken to attempt to modify this toxicity in a canine model that has been demonstrated to closely mimic the clinical situation. Unlike previous studies using this model, in which animals were sacrificed after extensive fibrosis had already occurred, the current experiments were designed so that observations of pathology were made at an earlier time, when the initial inflammatory injury underlying the fibrotic process was still taking place.

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Purpose: Amifostine is a prodrug in which selectivity is largely determined by the preferential formation and uptake of its cytoprotective metabolite, WR-1065, in normal tissues as a result of differences in membrane-bound alkaline phosphatase activity. It was hypothesized that amifostine may be a good candidate for regional drug delivery to the liver because of its large hepatic extraction and total body clearance.

Methods: Rat livers were implanted with Walker-256 tumors.

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Specific targeting and transgene expression in tumors are critical in adenovirus gene therapy for intrahepatic colon carcinoma metastases. In this study, we investigated if ionizing radiation could increase adenoviral uptake by cells. Various human cell lines and rat hepatocytes were irradiated prior to exposure to a cytomegalovirus (CMV) promoter-driven green fluorescent protein (GFP) marker gene adenoviral vector.

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A major potential limitation to the success of enzyme prodrug gene therapy is the toxicity that could result from gene expression in normal tissues. In this study, we investigated the use of an enhanced human carcinoembryonic antigen (CEA) promoter for yeast cytosine deaminase (yCD), which converts 5-fluorocytosine to 5-fluorouracil, to increase targeting while maintaining activity both in cell culture and in nude rats bearing intrahepatic xenografts. We found that an enhanced CEA-yCD adenoviral vector can achieve significantly greater yCD expression in CEA-expressing colon carcinoma cell lines (LoVo, HT29, and CaCo2) compared with a nonspecific Rous sarcoma virus-yCD virus.

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Amifostine is a prodrug in which selectivity is largely determined by the preferential formation and uptake of its cytoprotective metabolite, WR-1065, in normal tissues as a result of differences in membrane-bound alkaline phosphatase activity. In this study, we characterized the sites and extent of organ-specific activation by the liver, gastrointestinal tract, lungs, and kidneys after systemic administrations of amifostine. A total of 10 dogs were infused via the cephalic vein using sequential dose rates of drug at 0.

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Hepatic arterial (HA) infusional chemotherapy possesses a number of constraints not found with systemic chemotherapy. The drug used should have activity in a dose-responsive way without significant hepatic toxicity. The drug must also possess suitable pharmacokinetic properties, namely, a high total body clearance and hepatic extraction, so as to generate high hepatic and low systemic exposures.

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