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J M Hanson

Publications and source records attributed to J M Hanson.

At least 19 recordsLinked to original sources
PubMed2006

The leukemia inhibitory factor receptor gene is not involved in the etiology of pituitary dwarfism in German shepherd dogs.

Pituitary dwarfism in German shepherd dogs is characterized by combined pituitary hormone deficiency (CPHD) and intrapituitary cyst formation. Activation of the leukemia inhibitory factor (LIF)-LIF receptor (LIFR) signal transduction pathway results in a similar phenotype in (transgenic) mice. We therefore assessed the role of the LIFR in the etiology of pituitary dwarfism in German shepherd dogs. A polymorphic microsatellite marker (UULIFR) was used to analyze the segregation of the LIFR gene in 22 German shepherd dogs from 4 pedigrees, each including one dwarf. There was no allelic association between UULIFR and the dwarfism phenotype. Based on our findings LIFR was excluded as a candidate gene for CPHD.

Animals↗
PubMed2006

Use of the internet by colorectal cancer patients.

OBJECTIVE: To identify the frequency of Internet use by colorectal cancer patients. MATERIALS AND METHODS: Fifty patients interviews. RESULTS: Only four patients (8%) had used the internet to access information about colorectal cancer though 36% would have used it if a site had been recommended. CONCLUSION: The Internet is a resource rarely used by patients but there is potential for its use as an adjunct to written and verbal information.

Adult↗
PubMed2006

Plasma profiles of adrenocorticotropic hormone, cortisol, alpha-melanocyte-stimulating hormone, and growth hormone in dogs with pituitary-dependent hyperadrenocorticism before and after hypophysectomy.

The 6-h plasma profiles of adrenocorticotropic hormone (ACTH), cortisol, alpha-melanocyte-stimulating hormone (alpha-MSH), and GH were studied in 17 dogs with pituitary-dependent hyperadrenocorticism (PDH) before and after hypophysectomy. The aim of the study was to investigate the relation between the hormone profile characteristics and recurrence of PDH after surgery. The hormones were secreted in a pulsatile fashion. The basal plasma cortisol concentration and area under the curve (AUC) for cortisol were significantly higher in the PDH cases than in eight controls. The characteristics of the plasma profiles of ACTH and alpha-MSH were not significantly different between the PDH cases and the controls. In the PDH cases, less GH was secreted in pulses than in the controls, but the difference was not significant. The basal plasma cortisol concentration, the AUC for ACTH and cortisol, and the pulse frequency of ACTH and cortisol decreased significantly after hypophysectomy for the group of PDH cases. The basal plasma concentrations of ACTH and alpha-MSH, the AUC for alpha-MSH, and the characteristics of the plasma GH profiles of the PDH cases remained unchanged after hypophysectomy. No pulses of alpha-MSH were observed after hypophysectomy. The co-occurrence between the ACTH and cortisol pulses decreased significantly with hypophysectomy. The postoperative pulse frequency of ACTH was the only characteristic with predictive value for the recurrence of PDH after hypophysectomy. The results of this study demonstrate that ACTH, cortisol, alpha-MSH, and GH are secreted in a pulsatile fashion in dogs with PDH. Hypophysectomy effectively reduces the secretion of ACTH and cortisol. The presence of ACTH pulses after hypophysectomy is a risk factor for the recurrence of hyperadrenocorticism.

Adrenocortical Hyperfunction↗
PubMed2005

Anomalous unilateral single pulmonary vein: two cases mimicking arteriovenous malformations and a review of the literature.

Total anomalous pulmonary venous drainage is a rare congenital anomaly. It usually involves a pulmonary to systemic venous shunt and most cases have a septal defect in order to survive. Anomalous pulmonary venous drainage with pulmonary venous shunting is an extremely rare and entirely benign entity. We present two such cases, in which there was atresia of the left superior pulmonary vein and drainage via a tortuous collateral vein to the left inferior pulmonary vein. This collateral was mistaken on plain film and CT for a pulmonary arteriovenous malformation. Awareness of this anomalous unilateral single pulmonary vein and its radiological appearances may help in avoiding unnecessary pulmonary angiography.

Adult↗
PubMed2001

Phosphatidylinositol 3-kinase, not extracellular signal-regulated kinase, regulates activation of the antioxidant-responsive element in IMR-32 human neuroblastoma cells.

The antioxidant-responsive element (ARE) plays an important role in the induction of phase II detoxifying enzymes including NADPH:quinone oxidoreductase (NQO1). We report herein that activation of the human NQO1-ARE (hNQO1-ARE) by tert-butylhydroquinone (tBHQ) is mediated by phosphatidylinositol 3-kinase (PI3-kinase), not extracellular signal-regulated kinase (Erk1/2), in IMR-32 human neuroblastoma cells. Treatment with tBHQ significantly increased NQO1 protein without activation of Erk1/2. In addition, PD 98059 (a selective mitogen-activated kinase/Erk kinase inhibitor) did not inhibit hNQO1-ARE-luciferase expression or NQO1 protein induction by tBHQ. Pretreatment with LY 294002 (a selective PI3-kinase inhibitor), however, inhibited both hNQO1-ARE-luciferase expression and endogenous NQO1 protein induction. In support of a role for PI3-kinase in ARE activation we show that: 1) transfection of IMR-32 cells with constitutively active PI3-kinase selectively activated the ARE in a dose-dependent manner that was completely inhibited by treatment with LY 294002; 2) pretreatment of cells with the PI3-kinase inhibitors, LY 294002 and wortmannin, significantly decreased NF-E2-related factor 2 (Nrf2) nuclear translocation induced by tBHQ; and 3) ARE activation by constitutively active PI3-kinase was blocked completely by dominant negative Nrf2. Taken together, these data clearly show that ARE activation by tBHQ depends on PI3-kinase, which lies upstream of Nrf2.

Antioxidants↗
PubMed2001

Nrf2-dependent activation of the antioxidant responsive element by tert-butylhydroquinone is independent of oxidative stress in IMR-32 human neuroblastoma cells.

The antioxidant responsive element (ARE) is a cis-acting regulatory element located in the 5'-flanking region of several genes encoding phase II detoxification enzymes, including NAD(P)H:quinone oxidoreductase (NQO1). We report here that activation of the NQO1 ARE by tert-butylhydroquinone (tBHQ) is dependent on Nrf2 and not oxidative stress in IMR-32 human neuroblastoma cells. Overexpression of wild-type Nrf2 activated ARE in a dose-dependent manner, and ARE activation by tBHQ or diethyl maleate (DEM) was inhibited by dominant/negative Nrf2 not by dominant/negative c-Jun. According to our observation, the palindromic sequence (5' to the core) and the GC box in the ARE core sequence are essential for maximal inducibility by tBHQ or DEM. Overexpression of Nrf2 selectively activated wild-type ARE up to 24 h. In addition, a dramatic nuclear translocation of Nrf2 by tBHQ supports a role for Nrf2 in ARE activation. Although oxidative stress is hypothesized to be a major driving force for ARE activation, pretreatment of antioxidant or antioxidant enzyme did not block tBHQ-mediated ARE activation. In contrast, ARE activation by DEM was inhibited by antioxidants or catalase. These results suggest that ARE activation signals from tBHQ and DEM converge at Nrf2 transcription factor through independent mechanisms.

Antioxidants↗
PubMed2001

Rectal retroflexion: an essential part of lower gastrointestinal endoscopic examination.

PURPOSE: Retroflexion of the endoscope during rectal examination may increase diagnostic yield but is not routinely performed because of concerns about safety and a lack of appreciation of its importance. The purpose of this study was to examine the yield, safety, and tolerance of endoscopic rectal retroflexion. METHODS: Prospective cohorts of subjects undergoing unsedated screening flexible sigmoidoscopy were examined with and without routine retroflexion. Pain scores were recorded. RESULTS: A total of 526 subjects (mean age 60 (range, 55-66) years) underwent flexible sigmoidoscopy in the first period when the endoscope was not routinely retroflexed. Of these, 480 (mean age 60 (range, 55-66) years) were subsequently examined with routine retroflexion. Retroflexion was impossible in 17 subjects (3.5 percent) because of discomfort. In the second group, 12 subjects (2.5 percent) had polyps in the lower rectum seen only on retroflexion. Of these, eight had metaplastic and four had adenomatous polyps (3 tubular <5 mm, 1 tubulovillous 15 mm). There was no difference in mean pain scores between the groups (no retroflexion = 2.13, retroflexion = 2.18). CONCLUSION: With an adenoma pick-up rate of 8 to 12 percent for screening flexible sigmoidoscopy, retroflexion increases adenoma detection by approximately 1 percent without adverse effects and should be an integral part of flexible sigmoidoscopy.

Adenoma↗
PubMed2001

MUC1 expression in primary breast cancer: the effect of tamoxifen treatment.

This was a non-randomised single institution retrospective study. Forty-six banked frozen tumour specimens were obtained from a group of patients who had undergone 3 weeks of neoadjuvant treatment with tamoxifen between biopsy and surgery. Fifty-one comparison specimens were randomly selected from a group of concomitantly treated primary breast cancer patients who did not receive neoadjuvant tamoxifen. Specimen selection was not based on prognostic factors: hormone receptor status, patient age, or menopausal status. MUC1 expression and cell cycle distribution were assessed by flow cytometry. S-phase fraction of MUC1 positive and MUC1 negative cells were compared. A lower percentage of cells expressed MUC1 following 3-week tamoxifen treatment 18.2% versus 28.5% (p = 0.03, Mann-Whitney) and lower levels of MUC1 expression were seen following tamoxifen treatment 31,519 molecules/cell versus 39,387 (p = 0.04, Mann-Whitney). MUC1 positive cells, irrespective of treatment group, had a greater proportion of cells in S-phase of the cell cycle 27.9% versus 16.8% (p = 0.0004, Mann-Whitney) and demonstrated more cases of aneuploidy 80.65% versus 42.6% (p < 0.0001). MUC1 levels in primary tumours treated neoadjunctively with 3 weeks of tamoxifen were lower than a comparison group which did not receive tamoxifen. MUC1 should be explored further as an intermediate biomarker for assessment of treatment and prognosis.

Aged↗
PubMed2001

Blind percutaneous insertion of Hickman lines by a specialist team.

BACKGROUND: Long-term intravenous lines for the delivery of chemotherapy can be inserted by the percutaneous route or under direct vision by surgical exploration. Though the percutaneous route is widely used, many centres still employ a surgical approach. This study evaluates the safety of the blind percutaneous approach. METHOD: Prospective records were kept of all Hickman lines inserted on the oncology unit of a large teaching hospital. RESULTS: 127 consecutive lines were inserted in 115 adults by a single surgeon over a 30 month period using a blind percutaneous approach. There were 4 complications of insertion: 2 pneumothoraces (1.6%), 1 arrhythmia (0.8%) and bleeding from the subcutaneous tunnel (0.8%). Only 1 line had to be removed in the first 14 days because of hub fracture and leakage. CONCLUSIONS: Percutaneous insertion of Hickman lines using the blind technique is associated with a low incidence of complications when performed by an experienced operator.

Adult↗
PubMed2000

Whole body positron emission tomography imaging of activated lymphoid tissues during acute simian-human immunodeficiency virus 89.6PD infection in rhesus macaques.

Mechanisms of acute retroviral pathogenesis have been examined during primary infection of rhesus macaques with simian-human immunodeficiency virus 89.6PD (SHIV(89.6PD)). During acute infection, between initial exposure and establishment of antigen-specific immune responses that stabilize the virus burden, rapid immune system changes influence the viral set-point and dictate subsequent steps in disease progression. In a previous study, we described specific patterns of lymphocyte activation during acute SHIV(89.6PD) infection. We now extend these studies to describe lymphoid tissue activation, using whole body positron emission tomography (PET) and the radioactive tracer 2-[(18)F]fluorodeoxyglucose (FDG). Within a few days after primary infection by intravenous, intrarectal, or intravaginal routes, PET-FDG imaging revealed a distinct pattern of lymphoid tissue activation centered on axillary, cervical, and mediastinum lymph nodes. Increased tissue FDG uptake preceded fulminant virus replication at these sites, suggesting that a diffusible factor of host or viral origin was responsible for lymphoid tissue changes. These data show that activation of lymphoid tissues in the upper body is an early response to virus infection and that diffusible mediators of activation might be important targets for vaccine or therapeutic intervention strategies.

Acute Disease↗
PubMed2000

Manual rotational testing of the vestibulo-ocular reflex.

OBJECTIVES/HYPOTHESIS: Manual whole-body and head-on-body rotational testing of the vestibuloocular reflex (VOR) is comparable to conventional rotary chair methods with and without visual fixation from 0.025 to 1 Hz. STUDY DESIGN: Summary of four previously published trials from our laboratory and a fifth prospective blinded study comparing whole-body and head-on-body rotation with rotational chair results from 0.025 to 1 Hz in 10 patients with bilateral vestibular dysfunction. METHODS: Subjects were fitted with standard electro-oculogram (EOG) electrodes and placed in the rotary chair for testing at 0.025, 0.05, 0.1, 0.25, 0.5, and 1 Hz in the dark (VOR) and in the light with a stationary target (VVOR). They were then placed in an otolaryngology examination, chair where an adjustable headband containing the velocity sensor and an opaque visor were placed on the forehead. Whole-body rotational trials from 0.025 to 1 Hz and both passive and active head-on-body trials from 0.25 to 1 Hz were performed with and without visual fixation. Data from each frequency were analyzed cycle-by-cycle and averaged for gain, phase, and asymmetry. These values were then compared to the results obtained during rotational chair testing. RESULTS: Throughout the five studies, no systematic differences were noted between the manual rotational methods and the rotary chair results. Specifically, no consistent effect of volition or cervico-ocular reflex (COR) enhancement was demonstrated. CONCLUSIONS: Manual rotational testing is a reliable technique for measuring the VOR up to 1 Hz as compared with standard rotary chair methods. Advantages to this technique include portability, lower equipment costs, and potential application up to 6 Hz using head-on-body rotation.

Electronystagmography↗
PubMed2000

Laryngeal blastomycosis: a commonly missed diagnosis. Report of two cases and review of the literature.

Blastomycosis is a relatively uncommon fungal disease that most commonly affects the lungs. Other organs may be involved, usually secondary to dissemination of the organism. Laryngeal blastomycosis may occur in isolation from active pulmonary disease. The signs, symptoms, clinical features, and pathological findings of laryngeal blastomycosis mimic those of squamous cell carcinoma. Misdiagnosis may result in inappropriate treatment with potential morbidity. Proper understanding of the clinical presentation and familiarity with the histopathologic features of this disease are therefore imperative. In this paper, we report 2 cases of laryngeal blastomycosis, 1 of which was misdiagnosed as squamous cell carcinoma, clinically and microscopically, with consequent radiotherapy and laryngectomy. In the other case, a clinical diagnosis of glottic squamous cell carcinoma was rendered. However, blastomycosis was identified in a biopsy specimen. We also review cases of isolated laryngeal blastomycosis that have been reported in the English-language literature during the last 80 years. A number of those cases were misdiagnosed clinically and microscopically as squamous cell carcinoma.

Amphotericin B↗
PubMed2000

Thyroid aspiration cytology in Newcastle: a six year cytology/histology correlation study.

BACKGROUND: Fine needle aspiration cytology (FNAC) is a well-established technique for pre-operative investigation of thyroid nodule(s). Thyroid FNAC was introduced in the teaching hospitals of Newcastle upon Tyne in 1981, initially with a small group of clinicians as aspirators. Audit results for 1981-1986 inclusive showed an unsatisfactory rate of 25.3% and prediction of malignancy with a sensitivity of 93.5%. FNAC has become more popular locally for the investigation of thyroid disease and the number of clinicians performing aspirates has increased. The results for recent years have, therefore, been audited. METHODS: Medical records were reviewed for 239 patients with a dominant thyroid nodule who had FNAC carried out in the 6 year period 1990-1995 and subsequent partial or complete thyroidectomy. RESULTS: Histology of thyroid specimens showed 60 follicular adenomas and 34 malignant lesions (including 19 papillary, 10 follicular and 3 medullary carcinomas, one lymphoma and one follicular neoplasm with indeterminate malignant potential). A total of 302 FNAC had been carried out on these 239 patients. On cytological grounds the unsatisfactory sample (AC0 and AC1) rate was 43.1% on initial aspiration which was reduced to 32.2% on repeated aspiration. FNAC predicted neoplasia (AC3, AC4 and AC5) with a sensitivity of 86.8%, a specificity of 67.0%, a negative predictive value of 87.5% and a positive predictive value of 65.5%. Malignancy was predicted by FNAC (AC3, AC4 and AC5) with a sensitivity of 88.9%. A FNAC report of AC5 had a positive predictive value for malignancy of 100%. CONCLUSIONS: FNAC is an invaluable and minimally invasive procedure for the pre-operative assessment of patients with a dominant thyroid nodule. It is, however, important that the number of aspirators and cytopathologists be kept small to maintain expertise and also that the results of FNAC be subjected to ongoing audit.

Adolescent↗
PubMed2000

Metronidazole for bacterial vaginosis. A comparison of vaginal gel vs. oral therapy.

OBJECTIVE: To compare the efficacy and safety of 0.75% metronidazole vaginal gel with oral metronidazole for the treatment of bacterial vaginosis (BV). STUDY DESIGN: Nonpregnant women with BV were enrolled in a multicenter, randomized, investigator-blind treatment trial. Patients were randomly assigned to either 0.75% metronidazole vaginal gel (5 g twice daily for five days) or oral metronidazole (500 mg twice daily for seven days). Follow-up visits occurred approximately two and five weeks after initiation of therapy. RESULTS: BV was clinically eliminated at the first follow-up visit in 83.7% (36/43, 95% CI 72.3-95.1%) of the intravaginal group and 85.1% (40/47, 95% CI 74.6-95.6%) of the oral group. At the final visit, BV was eliminated in 70.7% (29/41, 95% CI 56.3-85.1%) of the intravaginal group and 71.1% (32/45, 95% CI 57.4-84.8%) of the oral group. Significantly more patients in the oral treatment group (51.8%) reported gastrointestinal complaints as compared to the intravaginal treatment group (32.7%, P = .04). CONCLUSION: The efficacy of 0.75% metronidazole vaginal gel twice daily for five days in treating BV was similar to that of standard oral metronidazole treatment and was associated with fewer gastrointestinal complaints.

Administration, Intravaginal↗
PubMed1999

Management of stage II (T2N0M0) glottic carcinoma by radiotherapy and conservation surgery.

BACKGROUND: The best therapeutic approach for the treatment of stage II (T2N0M0) glottic carcinoma is controversial. METHODS: A retrospective tumor registry data retrieval of patients with stage II glottic carcinoma treated with curative intent at Washington University Medical Center-Barnes Hospital between January 1971 and December 1989 (surgery) and December 1995 (radiotherapy) was performed. RESULTS: Among 134 patients with stage II glottic carcinomas treated with curative intent and function preservation, there were 47 patients treated with low dose radiotherapy (median dose, 58.5 Gy at 1.5-1.8 Gy daily fractions), 16 patients with high dose radiotherapy (67.5-70 Gy) at higher daily fractionation doses (2-2.25 Gy), and 71 patients underwent conservation surgery. The overall local control rate was 85%. The overall salvage rate was 68%. The 5-year actuarial and disease specific survivals were 81.5% and 92%, respectively. Unaided phonation was achieved in 84.4% of the patients. An incidence of 10.4% regional metastases, 2.2% distant metastases, and 6% second primary tumors was documented. There were no statistical differences in local control, voice preservation, and 5-year actuarial and disease specific cure rates between conservation surgery and high dose radiation (p = .89). Low dose radiation had statistically lower local controls, 5-year survival, and voice preservation (p = .014). In advanced T2B disease, treating the ipsilateral neck nodes reduced regional metastases (p = .02). CONCLUSIONS: High dose and daily fractionation (70 Gy at 2 Gy daily fraction doses) radiation achieved results equivalent to those of conservation surgery in 5-year local control, survival, and voice preservation. In advanced T2B disease, treatment of the ipsilateral neck nodes by radiotherapy or functional neck dissection reduced regional metastases.

Adult↗
PubMed1999

Stage I (T1 N0 M0) squamous cell carcinoma of the laryngeal glottis: therapeutic results and voice preservation.

BACKGROUND: The therapeutic outcomes for voice preservation in Stage I (T1 N0 M0) glottic carcinoma, treated with conservation surgery, radiation therapy, and endoscopic resection, are controversial. METHODS: A retrospective tumor registry retrieval of data on patients treated with curative intent at Washington University Medical Center-Barnes Hospital between January 1971 and December 1990 for the surgical group, January 1971 to December 1985 for the low-dose radiation group, and January 1986 to January 1995 for the high-dose radiation group, was performed. RESULTS: The 659 patients with Stage I (T1 N0 M0) glottic carcinoma treated with curative intent were subdivided into four groups: (1) 90 patients received low-dose radiation (mean dose 58 Gy, range 55-65 Gy, daily fractionation 1.5-1.8 Gy); (2) 104 patients received high-dose radiation (mean dose 66.5 Gy, range 65-70 Gy, daily fractionation 2-2.25 Gy); (3) 404 patients underwent conservation surgery; and (4) 61 patients had endoscopic resection. T1A (85%) and T1B (15%) disease was equally distributed among the groups. The anterior commissure was involved in 38 patients in the radiation therapy groups and 56 patients in the surgical groups. The overall local control was 89%. The overall local salvage was 84%. The overall unaided laryngeal voice preservation was 90%. The overall 5-year disease specific and actuarial survival rates were 95% and 81%, respectively. Prevalence of 2% regional metastases, 1.2% distant metastases, and 14% second primary malignancies were documented. The cure rate was 69% for regional metastases, 13% for distant metastases, and 44% for second primary malignancies. There were 5 complication deaths (0.1%), and 38 (6%) patients died of intercurrent disease. The use and dose of tobacco products was significantly increased in patients who died of intercurrent disease (p = 0.004) or developed second primary malignancies (p = 0.024). No significant difference was observed among the four therapeutic groups in the 5-year cause-specific survival rate (p, 0.68). Actuarial survival was significantly decreased in the low-dose radiation therapy group as compared with the other three therapeutic groups (p = 0.04). Initial local control was poorer for the endoscopic (77%) and low-dose radiation (78%) groups as compared with the high-dose radiation (89%) and conservation surgery (92%) groups (p = 0.02) but significant differences were not found for ultimate local control following salvage treatment. Unaided laryngeal voice preservation was similar for high-dose radiation (89%), conservation surgery (93%) and endoscopic resection (90%), but significantly poorer for low-dose radiation (80%; p = 0.02). T1B disease (N = 94) had similar local control and voice preservation with conservation surgery (87%) and high-dose radiation (88%) but lower results with low-dose radiation and endoscopic resections (67% unaided laryngeal voice preservation; p = 0.02). CONCLUSION: (1)The four therapeutic groups achieved similar rates of disease specific survival and ultimate local control. (2) Low-dose radiation was associated with significantly lower overall actuarial survival and unaided laryngeal voice preservation. (3) Endoscopic resection was associated with a significantly lower initial local control rate, but following salvage therapy achieved equivalent results to the other treatment methods. (4) Patients with (T1 N0 M0) glottic carcinoma had similar survival, local control, and unaided laryngeal voice preservation rates with high-dose radiation, conservation surgery, and endoscopic resections, but not with low-dose radiation therapy. (c) 1999 John Wiley & Sons, Inc. Head Neck 21: 707-717, 1999.

Adult↗