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D Driscoll

Publications and source records attributed to D Driscoll.

At least 19 recordsLinked to original sources
PubMed2006

Excitation spectrum of two correlated electrons in a lateral quantum dot with negligible Zeeman splitting.

The excitation spectrum of a two-electron quantum dot is investigated by tunneling spectroscopy in conjunction with theoretical calculations. The dot made from a material with negligible Zeeman splitting has a moderate spatial anisotropy leading to a splitting of the two lowest triplet states at zero magnetic field. In addition to the well-known triplet excitation at zero magnetic field, two additional excited states are found at finite magnetic field. The lower one is identified as the second excited singlet state on the basis of an avoided crossing with the first excited singlet state at finite fields. The measured spectra are in remarkable agreement with exact-diagonalization calculations. The results prove the significance of electron correlations and suggest the formation of a state with Wigner-molecular properties at low magnetic fields.

Journal Article↗
PubMed2006

Primary fallopian tube carcinoma: a retrospective clinicopathologic study.

INTRODUCTION: Primary fallopian tube carcinoma is a rare tumor. The aim of this study was to evaluate clinical characteristics and management of fallopian tube malignancies at a large tertiary care cancer institute. METHODS: A retrospective review of the Tumor Registry was conducted to identify all primary fallopian tube carcinomas between 1980 and 2001. Medical charts were retrospectively reviewed. Primary endpoints were overall survival and disease recurrence. RESULTS: Thirty-five patients had histology consistent with fallopian tube carcinoma. The median age at diagnosis was 56 years. The most common signs or symptoms were abnormal vaginal bleeding (29%) and abdominal/pelvic mass (26%). The most common histology was adenocarcinoma in 16 (46%) patients. Five patients (14%) were Stage I, seven patients (20%) Stage II, 17 patients (49%) Stage III and six patients (17%) Stage IV. Thirty-two (91%) patients received adjuvant chemotherapy and 77% received platinum-based chemotherapy. Twenty-seven (77%) patients underwent second-look surgery, of which 17 patients (63%) were positive for disease. The 5-year survival rate was 64% for Stage I, 42% for Stage II, 32% for Stage III, and 17% for Stage IV. CONCLUSIONS: Fallopian tube malignancies are rare and carry a poor prognosis. More extensive research needs to be performed to have definitive etiologic, diagnostic and treatment guidelines.

Adult↗
PubMed2003

Evidence for a strong surface-plasmon resonance on ErAs nanoparticles in GaAs.

Room-temperature attenuation measurements are made between lambda=0.8 and 10.0 microm on three GaAs epitaxial samples containing layers of ErAs nanoparticles. An asymmetric attenuation peak is observed around 2.5 microm that increases in strength with ErAs density, and is modeled well by a Maxwell-Garnett formulation and semiclassical transport theory. The nanoparticles are assigned a distribution function of oblate spheroids having a minimum volume corresponding to a 1.0-nm sphere. This is consistent with the self-organizing tendency of ErAs in GaAs, and explains the sharp attenuation peak as a spherical-particle surface-plasmon (i.e., Fröhlich) resonance.

Journal Article↗
PubMed2002

Dynamics of inter-landau-level excitations of a two-dimensional electron gas in the quantum Hall regime.

The femtosecond inter-Landau-level dynamics of a two-dimensional electron gas in a large magnetic field is investigated by degenerate four-wave mixing on modulation doped quantum wells. We observe a large transfer of oscillator strength to the lowest Landau level, and unusual dynamics due to Coulomb correlation. We interpret the effects using a model based on shakeup of the electron gas.

Journal Article↗
PubMed2001

Angelman syndrome: mimicking conditions and phenotypes.

The diagnosis of Angelman syndrome (AS) can be confirmed by genetic laboratory in about 80% of cases. In 20%, the diagnosis remains clinical, but often there is uncertainty about the correctness of the clinical diagnosis and alternative diagnoses may be investigated. In evaluating individuals for AS in our center since 1989, we have encountered several mimicking conditions, and additional ones have been reported in the literature. Mimicking conditions can be grouped into the areas of chromosome, single gene, and symptom complex anomalies. Microdeletions or microduplications include chromosome regions 2,4,17, 22, and 15. Single gene conditions include methylene tetrahydrofolate reductase deficiency (MTHFR), Rett syndrome, alpha-thalassemia retardation syndrome (ATR-X), and Gurrieri syndrome. Symptom complexes include cerebral palsy, static encephalopathy, Lennox-Gastaut syndrome, autism spectrum disorder, pervasive developmental delay (PDD), and mitochondrial disorders. We present a review of these mimicking disorders to increase the awareness about conditions that can lead to an incorrect clinical diagnosis of AS.

Angelman Syndrome↗
PubMed2001

Early postoperative oral feeding after colectomy: an analysis of factors that may predict failure.

BACKGROUND: Previous studies have shown that early postoperative oral feeding is feasible. Traditionally patients were fed when flatus or defecation documented the return of bowel function. This study was undertaken to determine factors that may preclude early feeding. METHODS: One hundred four successive patients underwent colorectal surgery from October 1999 to January 2001. Eighty-nine patients started an oral diet either on postoperative day 1 or 2. Their clinical outcomes were recorded prospectively. Fifteen of the 104 patients were excluded for small-bowel resection (5 patients), perioperative complications (5 patients), prior radiation (3 patients), and small-bowel obstruction (2 patients). A failure in postoperative feeding consisted of nausea, vomiting, or readmission. RESULTS: The mean age of our cohort was 65 years (range, 28-87 years). There were 45 male and 44 female patients. The mean postoperative hospital stay was 6 days (range, 3-13 days). The median American Society of Anesthesiology score was II (range, I-IV). The types of resection performed were right colectomy (27 patients), low anterior resection (26 patients), sigmoid resection (11 patients), abdominoperineal resection (8 patients), formation or closure of colostomy (7 patients), posterior pelvic exenteration (4 patients), total colectomy (3 patients), left colectomy (2 patients), and transverse colectomy (1 patient). Sixty-five patients (73%) tolerated early oral feeding. Of the 24 patients that did not, 16 had nausea or emesis, and 8 required readmission for postoperative complications (small-bowel obstruction [4 patients], wound dehiscence [1 patient], abdominal pain [1 patient], and anastomotic leak [2 patients]). Univariate analysis revealed that the use of volume expanders contributed to intolerance of early feeding. On multivariate analysis, blood loss during the operation was the only factor contributing to failure of early postoperative oral feeding. CONCLUSIONS: Early oral feeding is safe and feasible for postcolectomy patients with a history of colorectal neoplasms.

Adult↗
PubMed2001

Malignant fibrous histiocytoma: an institutional review.

BACKGROUND: A thorough understanding of malignant fibrous histiocytoma (MFH), the most common subtype of soft tissue sarcoma, will lead to improved histologic-specific protocols. METHODS: 126 patients with histologically confirmed MFH were analyzed. The median follow-up was 42 months (range 1-233 months). RESULTS: Overall survival was 58% at 5 years and 38% at 10 years. Grade significantly influenced prognosis, with 10-year survival of 90%, 60%, and 20% for low, intermediate, and high grade tumors, respectively (p = 0.0007). Distant metastases at initial presentation (p = 0.0002) and size of the primary tumor (p = 0.0007) influenced outcome. Neither anatomic site nor depth of the primary tumor were significant prognostic factors. Positive microscopic margins were associated with a decreased disease-free survival (p = 0.006). CONCLUSIONS: Tumor grade, size, and distant metastases at initial presentation remain the most important prognostic factors for MFH. Resection with negative microscopic margins decreased the incidence of local recurrence.

Disease-Free Survival↗
PubMed2001

Is glucagonoma of the pancreas a curable disease?

BACKGROUND: Glucagonomas are rare neuroendocrine tumors of the pancreas. Because of its rarity, its natural history is not well understood. AIM: We evaluated the natural history of glucagonomas treated at a tertiary care cancer center. METHODS: A retrospective analysis of 12 patients during 1970 to 2000 was performed. Six patients (50%) had a tumor located in the head of the pancreas. RESULTS: Abdominal pain (83%) and weight loss (75%) were the most common symptoms. Median tumor size was 6 cm (range 0.04-10). Seven patients (58%) had liver metastases. Five patients (42%) underwent curative resection. Overall median survival was 66 mo, and 5-yr overall survival was 66%. Five-yr overall survival was 83% for patients who had resection versus 50% for the non-resected patients (p = 0.04). Patients who were disease-free had a complete resection of the primary tumor and no liver involvement. CONCLUSIONS: Glucagonomas generally present with liver metastases at the time of diagnosis. Cure is only possible if the disease is localized and completely resected.

Adult↗
PubMed2000

Exclusion limits on the WIMP-nucleon cross section from the cryogenic dark matter search.

The Cryogenic Dark Matter Search (CDMS) employs Ge and Si detectors to search for weakly interacting massive particles (WIMPs) via their elastic-scattering interactions with nuclei while discriminating against interactions of background particles. CDMS data, accounting for the neutron background, give limits on the spin-independent WIMP-nucleon elastic-scattering cross section that exclude unexplored parameter space above 10 GeV/c2 WIMP mass and, at >75% C.L., the entire 3sigma allowed region for the WIMP signal reported by the DAMA experiment.

Journal Article↗
PubMed2000

Pathologic and clinical features influencing outcome of thin cutaneous melanoma: correlation with newly proposed staging system.

The incidence of malignant melanoma is increasing. Because of increased awareness, early recognition of malignant melanoma has become more common. In 1997, a new staging system for cutaneous melanoma was proposed, with reclassification of thin melanoma < 1 mm, with and without ulceration. This report evaluates the pathologic and clinical features of thin melanomas influencing recurrence and survival from a tertiary cancer center in an attempt to correlate findings with the proposed staging system. A review of the Roswell Park Cancer Institute tumor registry identified 352 patients with thin cutaneous melanomas (< 1.0 mm) seen during an 18-year period ending August 30, 1998. Overall survival was 93 and 87 per cent at 5 and 10 years, respectively. Disease-free survival was 94 and 93 per cent at 5 and 10 years, respectively. Local recurrence occurred in 3 per cent of patients, regional recurrence in 3 per cent, and metastatic disease in 3 per cent, for an overall recurrence of 7 per cent, with a median follow-up of 118 months. Only the presence of ulceration was a significant prognostic factor for recurrence by both univariate and multivariate analysis. Failure rates (any recurrence) by Clark levels I, II, and III/IV were 3, 5, and 10 per cent, respectively (P = 0.14). Failure rates by tumor thickness (mm), for 0.0-0.24, 0.25-0.49, 0.50-0.74, and 0.75-0.99 were 3, 4, 7, and 10 per cent, respectively (P = 0.49). Ten-year disease-free survival for ulceration versus no ulceration was 40 and 94 per cent, respectively (P < 0.0001). We conclude that thin cutaneous melanoma carries an excellent prognosis with appropriate treatment. Our findings support inclusion of ulceration in a new staging system. Lesions 0.76 to 0.99 mm and Clark level III and IV may warrant close observation as a separate subgroup.

Adult↗
PubMed2000

Searching for the polycystic ovary syndrome genes.

PCOS is a common disorder of unknown etiology. Studies of first-degree relatives of women diagnosed with PCOS suggest familial clustering of the disease. A prospective study of first-degree female relatives of women with PCOS conducted by NCPIR found that 46% of ascertainable sisters of women with PCOS were hyperandrogenemic. NCPIR has conducted linkage and association studies using affected sibling-pair analysis and the transmission/disequilibrium test to explore candidate PCOS genes. These studies point a finger at a region 1 MB centromeric to the insulin receptor gene on chromosome 19.

Female↗
PubMed1999

Downregulated gelsolin expression in hyperplastic and neoplastic lesions of the prostate.

BACKGROUND: Because of its role in cell motility and growth regulation, gelsolin, an actin-binding protein, has been considered a tumor suppressor and a potential prognostic marker in some neoplasias, such as breast and bladder cancer. Little is known about its immunoexpression in prostatic adenocarcinoma (PCA). METHODS: Formalin-fixed, paraffin-embedded tissues of 72 prostatectomy specimens with adenocarcinoma and 8 nonneoplastic prostates from autopsies were stained with a gelsolin monoclonal antibody using the Avidin-biotin-peroxidase complex (ABC) method after microwave antigen retrieval. Immunoreactivity was evaluated in PCA, prostatic intraepithelial neoplasia (PIN), benign prostatic hyperplasia (BPH), and nonproliferative glandular tissue and stroma. The results were statistically analyzed. RESULTS: Consistent gelsolin immunoreactivity was seen in prostatic stromal cells, smooth muscle, endothelia, and nerves. Variable gelsolin expression was seen in 20-100% (average (A) = 65.5%) of glandular cells in nonproliferative tissue (N = 75); 0-50% (A = 9.7%) in BPH (N = 59); 0-80% (A = 8.9%) in PIN (N = 61); and 0-90% (A = 9.3%) in PCA (N = 71). The level of gelsolin expression in nonproliferative prostatic tissue was similar between prostates with PCA (A = 63.4%) and nonneoplastic prostates (A = 67.5%). The level of gelsolin expression did not correlate with age, tumor size, Gleason score, or stage. CONCLUSIONS: Gelsolin is decreased in PCA, PIN, and BPH in comparison to nonproliferative tissue. The role of this downregulation in the development of PCA is not clear. The similar reduction seen in PIN and BPH suggests that this event takes place indiscriminately in hyperplasia and early tumorigenesis in the prostate, which might limit its prognostic significance in PCA.

Adenocarcinoma↗
PubMed1999

Anti-angiogenic activity of selected receptor tyrosine kinase inhibitors, PD166285 and PD173074: implications for combination treatment with photodynamic therapy.

Angiogenesis, the formation of new blood vessels from an existing vasculature, is requisite for tumor growth. It entails intercellular coordination of endothelial and tumor cells through angiogenic growth factor signaling. Interruption of these events has implications in the suppression of tumor growth. PD166285, a broad-spectrum receptor tyrosine kinase (RTK) inhibitor, and PD173074, a selective FGFR1TK inhibitor, were evaluated for their anti-angiogenic activity and anti-tumor efficacy in combination with photodynamic therapy (PDT). To evaluate the anti-angiogenic and anti-tumor activities of these compounds, RTK assays, in vitro tumor cell growth and microcapillary formation assays, in vivo murine angiogenesis and anti-tumor efficacy studies utilizing RTK inhibitors in combination with photodynamic therapy were performed. PD166285 inhibited PDGFR-beta-, EGFR-, and FGFR1TKs and c-src TK by 50% (IC50) at concentrations between 7-85 nM. PD173074 displayed selective inhibitory activity towards FGFR1TK at 26 nM. PD173074 demonstrated (>100 fold) selective growth inhibitory action towards human umbilical vein endothelial cells compared with a panel of tumor cell lines. Both PD166285 and PD173074 (at 10 nM) inhibited the formation of microcapillaries on Matrigel-coated plastic. In vivo anti-angiogenesis studies in mice revealed that oral administration (p.o.) of either PD166285 (1-25 mg/kg) or PD173074 (25-100 mg/kg) generated dose dependent inhibition of angiogenesis. Against a murine mammary 16c tumor, significantly prolonged tumor regressions were achieved with daily p.o. doses of PD166285 (5-10 mg/kg) or PD173074 (30-60 mg/kg) following PDT compared with PDT alone (p<0.001). Many long-term survivors were also noted in combination treatment groups. PD166285 and PD173074 displayed potent anti-angiogenic and anti-tumor activity and prolonged the duration of anti-tumor response to PDT. Interference in membrane signal transduction by inhibitors of specific RTKs (e.g. FGFR1TK) should result in new chemotherapeutic agents having the ability to limit tumor angiogenesis and regrowth following cytoreductive treatments such as PDT.

Angiogenesis Inhibitors↗
PubMed1999

Soft tissue sarcoma of the hand.

A retrospective review of our institute's tumor registry from January 1972 to January 1996 revealed 24 patients with a diagnosis of primary soft tissue sarcoma of the hand, from a total of 570 extremity soft tissue sarcomas (4%). The most frequent histologic type was malignant fibrous histiocytoma, which occurred in 9 (38%) of the 24 patients. The second most common histologic type was epithelioid sarcoma, which occurred in 6 (25%) patients. There was a statistically significant difference in the rate of local recurrence based on the type of treatment in which amputation was superior to the other forms of treatment. There was no statistically significant difference in the rate of distant failures between treatment groups. The estimated cumulative 5- and 10-year overall survival rates for all patients were 59% and 53%, respectively. Stage II patients had estimated cumulative 5- and 10-year survival rates of 68% and 59%, respectively. Stage III patients had a cumulative 5-year survival rate of 20%. Factors that were statistically significant in predicting survival were the size of the primary tumor, with tumors smaller than 5 cm having a better prognosis, and stage of the tumor at presentation, with stage I and II tumors having the highest survival rate. In selected patients with a primary hand sarcoma, aggressive limb-sparing surgery with adjuvant therapy offered equivalent survival compared with amputation.

Adolescent↗
PubMed1999

Prognostic factors affecting survival in patients with colorectal carcinomatosis.

This study evaluates prognostic factors that may influence survival in patients who present with carcinomatosis from colorectal cancer. Patients may present with carcinomatosis as the pattern of metastases at the initial diagnosis of colorectal cancer. Little is known about the natural history of carcinomatosis and the prognostic factors affecting outcome. All patients treated at Roswell Park Cancer Institute from 1988 to 1994 who presented with carcinomatosis at the initial diagnosis of colorectal cancer were identified. A retrospective review of the medical records for patient and tumor demographics was performed. Estimated survival distributions were calculated by the method of Kaplan and Meier. Tests of significance with respect to survival distribution were based on the log-rank test. Cox proportional hazards model was used for the multivariate analysis. There were 31 males and 38 females. The median age was 61 years (range, 26-80). The primary cancers were in the sigmoid with 24 patients (35%), cecum with 14 patients (20%), and transverse colon with 11 patients (16%). The remainder were distributed throughout the colon and rectum. The most common presentation was large bowel obstruction in 29 patients (42%). T3 and T4 cancers were present in 39 (57%) and 13 patients (19%), respectively. Lymph nodes were positive in 39 patients (57%), and mucin-producing tumors were also present in 39 patients (57%). Twelve patients (17%) had one site of disease, 17 patients (25%) had two sites of disease, and 37 (54%) patients had three or more sites of disease. Ascites was present in 29 patients (42%). Residual disease was present at the completion of surgery in 45 patients, absent in 13 patients, and status unknown in 11. The presence of residual disease (p = 0.0001), presence of ascites (p = 0.02), stage greater than T3 (p = 0.02), and increasing number of carcinomatosis sites (p = 0.006) were found to have a negative impact on survival on univariate analysis. On multivariate analysis, only the presence of residual disease at the completion of surgery was found to be an independent predictor of survival (p = 0.04). Overall median survival was 14 months with a 26% estimated 2-year survival. The presence of gross residual disease at the completion of surgery was shown to be the only independent factor negatively affecting survival. This has potential implications for the operative management of patients presenting with colorectal carcinomatosis.

Adenocarcinoma↗
PubMed1999

The Philadelphia story: the 22q11.2 deletion: report on 250 patients.

A submicroscopic deletion of chromosome 22q11.2 has been identified in the majority of patients with the DiGeorge, velocardiofacial, and conotruncal anomaly face syndromes, and in some patients with the Opitz G/BBB and Cayler cardiofacial syndromes. We have been involved in the analysis of DiGeorge syndrome and related diagnoses since 1982 and have evaluated a large number of patients with the deletion. We describe our cohort of 250 patients whose clinical findings help to define the extremely variable phenotype associated with the 22q11.2 deletion and may assist clinicians in providing genetic counseling and guidelines for clinical management based on these findings.

Abnormalities, Multiple↗
PubMed1998

Evidence for a genetic basis for hyperandrogenemia in polycystic ovary syndrome.

Our preliminary family studies have suggested that some female first-degree relatives of women with polycystic ovary syndrome (PCOS) have hyperandrogenemia per se. It was our hypothesis that this may be a genetic trait and thus could represent a phenotype suitable for linkage analysis. To investigate this hypothesis, we examined 115 sisters of 80 probands with PCOS from unrelated families. PCOS was diagnosed by the combination of elevated serum androgen levels and </=6 menses per year with the exclusion of secondary causes. The sisters were compared with 70 healthy age- and weight-comparable control women with regular menses, no clinical evidence of hyperandrogenemia, and normal glucose tolerance. Twenty-two percent of the sisters fulfilled diagnostic criteria for PCOS. In addition, 24% of the sisters had hyperandrogenemia and regular menstrual cycles. Circulating testosterone (T) and nonsex hormone-binding globulin-bound testosterone (uT) levels in both of these groups of sisters were significantly increased compared with unaffected sisters and control women (P < 0.0001 for both T and uT). Probands, sisters with PCOS, and hyperandrogenemic sisters had elevated serum luteinizing hormone levels compared with control women. We conclude that there is familial aggregation of hyperandrogenemia (with or without oligomenorrhea) in PCOS kindreds. In affected sisters, only one-half have oligomenorrhea and hyperandrogenemia characteristic of PCOS, whereas the remaining one-half have hyperandrogenemia per se. This familial aggregation of hyperandrogenemia in PCOS kindreds suggests that it is a genetic trait. We propose that hyperandrogenemia be used to assign affected status in linkage studies designed to identify PCOS genes.

Adolescent↗