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Debbie Smith

Publications and source records attributed to Debbie Smith.

At least 19 recordsLinked to original sources
PubMed2006

Photofrin uptake in the tumor and normal tissues of patients receiving intraperitoneal photodynamic therapy.

PURPOSE: A phase II trial of Photofrin-mediated i.p. photodynamic therapy shown in a previous report limited efficacy and significant acute, but not chronic, toxicity. A secondary aim of this trial and the subject of this report is to determine Photofrin uptake in tumor and normal tissues. EXPERIMENTAL DESIGN: Patients received Photofrin, 2.5 mg/kg, i.v., 48 hours before debulking surgery. Photofrin uptake was measured by spectroflurometric analysis of drug extracted from tumor and normal tissues removed at surgery. Differences in drug uptake among these tissues were statistically considered using mixed-effects models. RESULTS: Photofrin concentration was measured in 301 samples collected from 58 of 100 patients enrolled on the trial. In normal tissues, drug uptake significantly (P<0.0001) differed as a function of seven different tissue types. In the toxicity-limiting tissue of intestine, the model-based mean (SE) Photofrin level was 2.70 ng/mg (0.32 ng/mg) and 3.42 ng/mg (0.24 ng/mg) in full-thickness large and small intestine, respectively. In tumors, drug uptake significantly (P=0.0015) differed as a function of patient cohort: model-based mean Photofrin level was 3.32 to 5.31 ng/mg among patients with ovarian, gastric, or small bowel cancer; 2.09 to 2.45 ng/mg among patients with sarcoma and appendiceal or colon cancer; and 0.93 ng/mg in patients with pseudomyxoma. Ovarian, gastric, and small bowel cancers showed significantly higher Photofrin uptake than full-thickness large and/or small intestine. However, the ratio of mean drug level in tumor versus intestine was modest (<or=2.31). CONCLUSIONS: Some selectivity is found in Photofrin uptake between tumor and normal tissues of the peritoneal cavity, but absolute differences in drug uptake relative to toxicity-limiting normal tissues (intestine) are small. This narrow differential in drug selectivity likely contributes to a narrow window in therapeutic application, which has been previously reported.

Biopsy↗
PubMed2006

A phase II trial of intraperitoneal photodynamic therapy for patients with peritoneal carcinomatosis and sarcomatosis.

PURPOSE: A previous phase I trial of i.p. photodynamic therapy established the maximally tolerated dose of Photofrin (Axcan Pharma, Birmingham, AL)-mediated photodynamic therapy and showed encouraging efficacy. The primary objectives of this phase II study were to determine the efficacy and toxicities of i.p. photodynamic therapy in patients with peritoneal carcinomatosis and sarcomatosis. EXPERIMENTAL DESIGN: Patients received Photofrin 2.5 mg/kg i.v. 48 hours before debulking surgery. Intraoperative laser light was delivered to the peritoneal surfaces of the abdomen and pelvis. The outcomes of interest were (a) complete response, (b) failure-free survival time, and (c) overall survival time. Photosensitizer levels in tumor and normal tissues were measured. RESULTS: One hundred patients were enrolled into one of three strata (33 ovarian, 37 gastrointestinal, and 30 sarcoma). Twenty-nine patients did not receive light treatment. All 100 patients had progressed by the time of statistical analysis. The median failure-free survival and overall survival by strata were ovarian, 2.1 and 20.1 months; gastrointestinal cancers, 1.8 and 11.1 months; sarcoma, 3.7 and 21.9 months. Substantial fluid shifts were observed postoperatively, and the major toxicities were related to volume overload. Two patients died in the immediate postoperative period from bleeding, sepsis, adult respiratory distress syndrome, and cardiac ischemia. CONCLUSIONS: Intraperitoneal Photofrin-mediated photodynamic therapy is feasible but does not lead to significant objective complete responses or long-term tumor control. Heterogeneity in photosensitizer uptake and tumor oxygenation, lack of tumor specificity for photosensitizer uptake, and the heterogeneity in tissue optical properties may account for the lack of efficacy observed.

Adult↗
PubMed2006

Updated results of a phase I trial of motexafin lutetium-mediated interstitial photodynamic therapy in patients with locally recurrent prostate cancer.

Locally recurrent prostate cancer after treatment with radiation therapy is a clinical problem with few acceptable treatments. One potential treatment, photodynamic therapy (PDT), is a modality that uses laser light, drug photosensitizer, and oxygen to kill tumor cells through direct cellular cytotoxicity and/or through destruction of tumor vasculature. A Phase I trial of interstitial PDT with the photosensitizer Motexafin lutetium was initiated in men with locally recurrent prostate cancer. In this ongoing trial, the primary objective is to determine the maximally tolerated dose of Motexafin lutetium-mediated PDT. Other objectives include evaluation of Motexafin lutetium uptake from prostate tissue using a spectrofluorometric assay and evaluation of optical properties in the human prostate. Fifteen men with biopsy-proven locally recurrent prostate cancer and no evidence of distant metastatic disease have been enrolled and 14 have been treated. Treatment plans were developed using transrectal ultrasound images. The PDT dose was escalated by increasing the Motexafin lutetium dose, increasing the 732 ran light dose, and decreasing the drug-light interval. Motexafin lutetium doses ranged from 0.5 to 2 mg/kg administered IV 24, 6, or 3 hr prior to 732 ran light delivery. The light dose, measured in real time with in situ spherical detectors was 25-100 J/cm2. Light was delivered via optical fibers inserted through a transperineal brachytherapy template in the operating room. Optical property measurements were made before and after light therapy. Prostate biopsies were obtained before and after light delivery for spectrofluorometric measurements of photosensitizer uptake. Fourteen patients have completed protocol treatment on eight dose levels without dose-limiting toxicity. Grade I genitourinary symptoms that are PDT related have been observed. One patient had Grade II urinary urgency that was urinary catheter related. No rectal or other gastrointestinal PDT-related tox-icities have been observed to date. Measurements of Motexafin lutetium demonstrated the presence of photosensitizer in prostate tissue from all patients. Optical property measurements demonstrated substantial heterogeneity in the optical properties of the human prostate gland which supports the use of individualized treatment planning for prostate PDT.

Adenocarcinoma↗
PubMed2005

Role of T cells in innate and adaptive immunity against murine Burkholderia pseudomallei infection.

Antigen-specific T cells are important sources of interferon (IFN)-gamma for acquired immunity to intracellular pathogens, but they can also produce IFN- gamma directly via a "bystander" activation pathway in response to proinflammatory cytokines. We investigated the in vivo role of cytokine- versus antigen-mediated T cell activation in resistance to the pathogenic bacterium Burkholderia pseudomallei. IFN-gamma, interleukin (IL)-12, and IL-18 were essential for initial bacterial control in infected mice. B. pseudomallei infection rapidly generated a potent IFN-gamma response from natural killer (NK) cells, NK T cells, conventional T cells, and other cell types within 16 h after infection, in an IL-12- and IL-18-dependent manner. However, early T cell- and NK cell-derived IFN-gamma responses were functionally redundant in cell depletion studies, with IFN-gamma produced by other cell types, such as major histocompatibility complex class II(int) F4/80(+) macrophages being sufficient for initial resistance. In contrast, B. pseudomallei-specific CD4(+) T cells played an important role during the later stage of infection. Thus, the T cell response to primary B. pseudomallei infection is biphasic, an early cytokine-induced phase in which T cells appear to be functionally redundant for initial bacterial clearance, followed by a later antigen-induced phase in which B. pseudomallei-specific T cells, in particular CD4(+) T cells, are important for host resistance.

Animals↗
PubMed2005

Increased vaccine efficacy against tuberculosis of recombinant Mycobacterium bovis bacille Calmette-Guérin mutants that secrete listeriolysin.

The tuberculosis vaccine Mycobacterium bovis bacille Calmette-Guérin (BCG) was equipped with the membrane-perforating listeriolysin (Hly) of Listeria monocytogenes, which was shown to improve protection against Mycobacterium tuberculosis. Following aerosol challenge, the Hly-secreting recombinant BCG (hly+ rBCG) vaccine was shown to protect significantly better against aerosol infection with M. tuberculosis than did the parental BCG strain. The isogenic, urease C-deficient hly+ rBCG (DeltaureC hly+ rBCG) vaccine, providing an intraphagosomal pH closer to the acidic pH optimum for Hly activity, exhibited still higher vaccine efficacy than parental BCG. DeltaureC hly+ rBCG also induced profound protection against a member of the M. tuberculosis Beijing/W genotype family while parental BCG failed to do so consistently. Hly not only promoted antigen translocation into the cytoplasm but also apoptosis of infected macrophages. We concluded that superior vaccine efficacy of DeltaureC hly+ rBCG as compared with parental BCG is primarily based on improved cross-priming, which causes enhanced T cell-mediated immunity.

Adult↗
PubMed2005

Evaluation of vaccines in the EU TB Vaccine Cluster using a guinea pig aerosol infection model of tuberculosis.

The TB Vaccine Cluster project funded by the EU Fifth Framework programme aims to provide novel vaccines against tuberculosis that are suitable for evaluation in humans. This paper describes the studies of the protective efficacy of vaccines in a guinea pig aerosol-infection model of primary tuberculosis. The objective was to conduct comparative evaluations of vaccines that had previously demonstrated efficacy in other animal models. Groups of 6 guinea pigs were immunized with vaccines provided by the relevant EU Vaccine Cluster partners. Survival over 17 or 26 weeks was used as the principal measure of vaccine efficacy following aerosol challenge with H37Rv. Counts of mycobacteria in lungs and spleens, and histopathological changes in the lungs, were also used to provide evidence of protection. A total of 24 vaccines were evaluated in 4 experiments each of a different design. A heterologous prime-boost strategy of DNA and MVA, each expressing Ag85A and a fusion protein of ESAT-6 and Ag85B in adjuvant, protected the guinea pigs to the same extent as BCG. Genetically modified BCG vaccines and boosted BCG strategies also protected guinea pigs to the same extent as BCG but not statistically significantly better. A relatively high aerosol-challenge dose and evaluation over a protracted time post-challenge allowed superior protection over BCG to be demonstrated by BCG boosted with MVA and fowl pox vectors expressing Ag85A.

Aerosols↗
PubMed2005

Missed pills.

Explore the source record for details and available documents.

Contraceptives, Oral, Hormonal↗
PubMed2004

A phase I study of topical Tempol for the prevention of alopecia induced by whole brain radiotherapy.

PURPOSE: Complete alopecia is a universal complication of whole brain radiation therapy which contributes to patient anxiety over treatment. Tempol, a nitroxide radioprotector, has been shown to protect against radiation-induced alopecia in an animal model. This phase Ib study was designed to evaluate the safety and side effect profile of topical Tempol in patients with brain metastases being treated with whole brain radiotherapy. EXPERIMENTAL DESIGN: Twelve patients with metastatic cancer to the brain were enrolled in the study between October 2000 and February 2003. Tempol (70 mg/ml concentration solution) was applied topically to the scalp 15 minutes before and washed off immediately after the completion of each of 10 fractions of whole brain radiation. Pharmacokinetic studies to evaluate the systemic absorption of Tempol were performed. Patients were assessed for toxicity before, during, and after Tempol administration. A secondary end point of the study, hair retention, was also scored. RESULTS: Eleven patients were treated with topical Tempol. Adverse events that were considered possibly, probably, or definitely related to Tempol, included asymptomatic grade 2 (two patients) and grade 1 (one patient) hypoglycemia, grade 1 forehead skin redness (one patient), grade 1 dry scalp (one patient), and grade 1 tingling sensation on the scalp (one patient). Tempol was not detected in blood samples from more than 50% of the patients. Mean maximum Tempol levels for individual patients at any time point varied from 0.4 to 3.1 micromol/L. Hair retention was localized to the base of the scalp where the Tempol solution pooled after application in the first four patients on the study. Subsequently, full scalp hair retention was seen in three of final five evaluable patients after gauze had been wrapped around the head to hold the solution against the scalp. CONCLUSIONS: This study demonstrates that topical application of Tempol to the scalp before whole brain radiation is safe and well tolerated. Evidence of protection against radiation-induced alopecia was observed. A phase II study that uses a gel formulation to increase the exposure of scalp to Tempol has been initiated.

Administration, Topical↗
PubMed2004

A phase I trial of the dual farnesyltransferase and geranylgeranyltransferase inhibitor L-778,123 and radiotherapy for locally advanced pancreatic cancer.

PURPOSE: Preclinical and clinical studies have demonstrated that inhibition of prenylation can radiosensitize cell lines with activation of Ras and produce clinical response in patients with cancer. The aim of this study was to determine the maximally tolerated dose of the dual farnesyltransferase and geranylgeranyltransferase I inhibitor L-778,123 in combination with radiotherapy for patients with locally advanced pancreatic cancer. EXPERIMENTAL DESIGN: L-778,123 was given by continuous intravenous infusion with concomitant radiotherapy to 59.4 Gy in standard fractions. Two L-778,123 dose levels were tested: 280 mg/m2/day over weeks 1, 2, 4, and 5 for dose level 1; and 560 mg/m2/day over weeks 1, 2, 4, 5, and 7 for dose level 2. RESULTS: There were no dose-limiting toxicities observed in the eight patients treated on dose level 1. Two of the four patients on dose level 2 experienced dose-limiting toxicities consisting of grade 3 diarrhea in one case and grade 3 gastrointestinal hemorrhage associated with grade 3 thrombocytopenia and neutropenia in the other case. Other common toxicities were mild neutropenia, dehydration, hyperglycemia, and nausea/vomiting. One patient on dose level 1 showed a partial response of 6 months in duration. Both reversible inhibition of HDJ2 farnesylation and radiosensitization of a study patient-derived cell line were demonstrated in the presence of L-778,123. K-RAS mutations were found in three of the four patients evaluated. CONCLUSIONS: The combination of L-778,123 and radiotherapy at dose level 1 showed acceptable toxicity in patients with locally advanced pancreatic cancer. Radiosensitization of a patient-derived pancreatic cancer cell line was observed.

Adult↗
PubMed2004

Enhanced protection against tuberculosis by vaccination with recombinant Mycobacterium microti vaccine that induces T cell immunity against region of difference 1 antigens.

Mycobacterium microti, the vole bacillus, which was used as a live vaccine against tuberculosis until the 1970s, confers the same protection in humans as does Mycobacterium bovis bacille Calmette-Guerin (BCG). However, because the efficacy of the BCG vaccine varies considerably, we have tried to develop a better vaccine by reintroducing into M. microti the complete region of difference 1 (RD1), which is required for secretion of the potent T cell antigens early secreted antigen target (ESAT)-6 and culture filtrate protein (CFP)-10. The resultant recombinant strain, M. microti OV254::RD1-2F9, induced specific ESAT-6 and CFP-10 immune responses in mice with CD8(+) T lymphocytes that had strong expression of the CD44(hi) activation marker. This vaccine also displayed better efficacy against disseminated disease in the mouse and the guinea pig models of tuberculosis than was seen in animals vaccinated with M. microti alone or with BCG. The M. microti OV254::RD1-2F9 vaccine was less virulent and persistent in mice and than was BCG::RD1-2F9 may represent a safer alternative to BCG::RD1-2F9.

Animals↗
PubMed2004

Phase II trial of pleural photodynamic therapy and surgery for patients with non-small-cell lung cancer with pleural spread.

PURPOSE: Non-small-cell lung cancer (NSCLC) with pleural spread is incurable, with median survival rates ranging from 6 to 9 months. Surgery alone fails to locally control this disease or extend survival beyond the accepted treatment, palliative chemotherapy. METHODS: We conducted a phase II trial to evaluate the effects on local control and survival of combining surgery with intraoperative photodynamic therapy (PDT), a light-based cancer treatment, in patients with NSCLC with pleural spread. Patients received porfimer sodium (2 mg/kg), 24 hours before surgery, at which time all gross tumor was resected and followed by illumination of the hemithorax with 630 nm light to a measured dose of 30 J/cm(2). Photosensitizer levels in tumor and surrounding normal tissue were measured. RESULTS: Twenty-two patients with NSCLC were enrolled; 17 underwent complete debulking and PDT, three underwent partial debulking/PDT, and two patients were unresectable. Local control of pleural disease at 6 months was achieved in 11 of 15 (73.3%; 95% CI, 44.9% to 92.2%) assessable patients. Median overall survival for all 22 patients was 21.7 months (95% CI, 17.7 to 25.8 months). Measured levels of porfimer sodium in tumor were greater than those measured in normal tissues, with ratios ranging from 1.19 to 22.42. CONCLUSION: Our results indicate surgery and PDT can be performed safely with very good local control. The median survival of 21.7 months, calculated from the time of surgery and PDT is encouraging. Further evaluation of this therapy is warranted.

Adult↗
PubMed2004

Patterns of recurrence in patients treated with photodynamic therapy for intraperitoneal carcinomatosis and sarcomatosis.

The purpose of this study was to evaluate the patterns of recurrence in patients treated with Photofrin-mediated intraperitoneal photodynamic therapy (IP PDT). Sixty-six patients with gastrointestinal cancers, ovarian cancers, and sarcomas have been enrolled to date and 51 patients underwent IP PDT. Photofrin, 2.5 mg/kg, was administered intravenously 48 h prior to surgical debulking and intraoperative light treatment. Forty-five, and 49 patients were evaluable for response rates, and patterns of recurrence, respectively. Response to treatment was evaluated by CT or MRI scans of the abdomen and pelvis every 3 months. Patterns of recurrence were determined by evaluating the abdomen as a combination of different treatment regions. Of the 51 patients enrolled and treated with IP PDT two are alive without evidence of recurrence. Eleven of 45 patients showed no evidence of recurrence 3 months after treatment. No evidence of recurrence was noted in 7/17 sarcoma patients, 2 of 13 ovarian cancer patients, and 2 of 15 gastrointestinal cancer patients. The most common site of recurrence as determined by radiographs was the pelvis, which was noted in 19 of 49 (39%) patients. The presence of gross residual disease before light treatment (as determined by the attending surgeon) did not affect the site of recurrence. When studying those patients who had only locoregional recurrence, 9 of 33 evaluated radiographically and 10 of 24 evaluated operatively recurred only in peritoneal areas not previously involved with gross disease. The pelvis was the site with the highest rate of recurrence after IP PDT. A significant minority of patients recurred only in sites not previously involved with gross disease. Patients with gross residual disease before light therapy had similar recurrence rates to those without gross residual disease. Since sites involved with gross residual tumor often received boost doses of light, this could suggest a dose-response relationship for IP PDT.

Adult↗
PubMed2003

User satisfaction with allied health services delivered to residential facilities via videoconferencing.

We have investigated the role of videoconferencing in allied health service provision to high-care clients in rural residential facilities. Videoconferencing equipment was set up at a rural aged-care facility and a metropolitan allied health centre; ISDN transmission at 384 kbit/s was used to link the equipment. Twelve residents were assessed by both videoconference and face to face across five allied health disciplines (a total of 120 assessments). User satisfaction was measured using questionnaires and focus groups. Face-to-face assessment took significantly longer than videoconferencing assessment. However, the mean satisfaction ratings for face-to-face assessments were higher than for videoconferencing and the majority of the staff preferred the face-to-face format. Videoconferencing was particularly useful for consultations and the initial stages of the assessment process. A number of issues relating to the videoconferencing equipment, to the environment in which assessments were performed and to the clients themselves need to be addressed in order for this form of service delivery to be effective.

Aged↗
PubMed2003

Preliminary experience of allied health assessments delivered face to face and by videoconference to a residential facility for elderly people.

We investigated whether allied health assessments carried out via videoconferencing were comparable to assessments carried out face to face. Five allied health therapists (in dietetics, occupational therapy, physiotherapy, podiatry and speech pathology) conducted an assessment of 12 high-dependency residents both face to face and by videoconferencing. On a five-point Likert scale, the therapists' mean ratings for the efficiency and suitability of videoconferencing for assessment were significantly lower than for face to face. Their mean rating for the adequacy of their care plans was also significantly lower for videoconferencing than for face to face. However, in each case the dietician's assessments did not differ significantly between the two modalities. In 35 cases out of 60, two independent raters agreed that the therapists' care plans after the videoconferencing and face-to-face assessments were the same. However, the level of agreement between raters was only moderate (kappa=0.31). Despite the therapists' (natural) preference for face-to-face working, care plans formulated via videoconferencing were reasonably similar to those formulated in face-to-face assessment. Allied health assessments carried out by videoconferencing would therefore seem to be feasible.

Aged↗
PubMed2002

Videoconferencing in facilities providing care for elderly people.

Two studies were conducted to test the feasibility of delivering care by videoconferencing to facilities providing care for elderly people. Both used equipment connected by ISDN lines at 384 kbit/s. During the first study, no consultations, care plans or assessments were conducted. During the second study, 120 assessments were conducted in just over two weeks, both face to face and by videoconference. Why was one project so successful and the other not? The reasons related to ownership, planning, participants and location. A comparison of the two projects highlights some of the considerations necessary to ensure the success of any telehealth project.

Journal Article↗
PubMed2002

A Phase I trial of the farnesyltransferase inhibitor L-778,123 and radiotherapy for locally advanced lung and head and neck cancer.

PURPOSE: Preclinical data have demonstrated that farnesyltransferaseinhibitors (FTIs) are radiation sensitizers in selected cell lines. The objective of this Phase I trial was to determine the maximally tolerated dose of the FTI L-778,123 in combination with radiotherapy in non-small cell lung cancer (NSCLC) and head and neck cancer (HNC). EXPERIMENTAL DESIGN: L-778,123 was given by continuous i.v. infusion and dose escalated in conjunction with standard radiotherapy. The presence of a ras mutation was not required for study entry. RESULTS: Nine patients (six NSCLC patients and three HNC patients) were enrolled on two dose levels of FTI. No dose-limiting toxicities were observed at the first dose level of 280 mg/m2/day during weeks 1, 2, 4, and 5 of radiotherapy. One episode of dose-limiting toxicity, grade IV neutropenia, was observed in one of three patients treated at 560 mg/m2/day during weeks 1, 2, 4, 5, and 7. No episodes of dose-limiting mucositis, esophagitis, or pneumonitis were observed. Of the four patients with NSCLC with evaluable disease, three patients had a complete response to treatment and one patient had a partial response. A complete clinical response to treatment was observed in two patients with HNC. In vitro studies in tumor cells obtained from a NSCLC patient on this trial showed radiosensitization with FTI and that tumor cells accumulated in G2-M after L-778,123 treatment. CONCLUSIONS: The combination of L-778,123 and radiotherapy at dose level 1 is associated with acceptable toxicity. Local responses have been observed in four NSCLC patients without a clear increase in radiotherapy-associated toxicities.

Adult↗