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P Huber

Publications and source records attributed to P Huber.

At least 37 records · Page 2Linked to original sources
PubMed2002

Tetra point wetting at the free surface of liquid Ga-Bi.

A continuous surface wetting transition, pinned to a solid-liquid-liquid-vapor tetra coexistence point, is studied by x-ray reflectivity in liquid Ga-Bi binary alloys. The short-range surface potential is determined from the measured temperature evolution of the wetting film. The thermal fluctuations are shown to be insufficient to induce a noticeable breakdown of mean-field behavior, expected in short-range-interacting systems due to their d(u) = 3 upper critical dimensionality.

Journal Article↗
PubMed2002

How sensitive is a neutrino factory to the angle theta(13)?

We consider the impact of nonstandard interactions (NSI) of neutrinos on the determination of neutrino mixing parameters at a neutrino factory using nu(-)(e)-->nu(-)(mu) "golden channels" for the measurement of theta(13). We show how a small residual NSI leads to a drastic loss in sensitivity in theta(13), of up to 2 orders of magnitude. This can be somewhat overcome if two baselines are combined.

Journal Article↗
PubMed2002

Basal TSH levels compared with TRH-stimulated TSH levels to diagnose different degrees of TSH suppression: diagnostic and therapeutic impact of assay performance.

BACKGROUND: The estimated prevalence of endogenous subclinical hyperthyroidism varies from 4% to 6% and a basal thyroid stimulating hormone (TSH) level < 0.5 mU L-1 may be associated with increased mortality in subjects over 60 years of age who are not on thyroid medication. Exogenous TSH suppression is a mainstay in the treatment of thyroid cancer. Because of recent concerns about potential adverse effects, especially of endogenous TSH suppression on bone, the cardiovascular system and cognitive functions, subclinical hyperthyroidism obtained new clinical importance. We therefore re-evaluated the diagnostic value of basal and thyrotrop in TRH-stimulated serum TSH measurements using TSH assays with different sensitivities. MATERIALS AND METHODS: A total of 805 oral and nasal TRH stimulation tests were performed on 409 ambulatory subjects with low basal serum TSH concentrations of less than 0.1 mIU L-1. Basal serum TSH was measured either using a second generation assay (functional sensitivity > 0.03 mIU L-1) or two third generation assays (functional sensitivity 0.01 mIU L-1 and 0.007 mU L-1, respectively). Serum TSH concentration was determined before and 3 h after oral administration of 40 mg of TRH and before and 30 min after nasal administration of 2 mg of TRH. RESULTS: In the oral testing group, the basal TSH levels measured by the different TSH assays were 0.06 +/- 0.03, 0.04 +/- 0.02 and 0.03 +/- 0.02, respectively, whereas the peak TSH levels were 0.4 +/- 0.6, 0.4 +/- 0.6 and 0.3 +/- 0.5 in the patients with subclinical hyperthyroidism. In overt hyperthyroidism, the basal TSH levels were 0.06 +/- 0.02, 0.03 +/- 0.02 and 0.03 +/- 0.02, whereas the peak TSH levels were 0.19 +/- 0.3, 0.16 +/- 0.3 and 0.15 +/- 0.2, respectively. Basal TSH values could discriminate between different degrees of TSH suppression if measured with a third generation assay (P < 0.001), but not with a second generation assay. There was only a weak correlation between basal TSH and peak TSH when measured by a second generation assay (n = 126; r = 0.3; P < 0.001) in contrast to the strong correlation found using the third generation assays (n = 128; r = 0.7; P < 0.001 and n = 69; r = 0.8; P < 0.001, respectively). CONCLUSIONS: In view of the recent concerns about potential adverse effects in TSH suppression and based on our data, it is mandatory to select a TSH assay with a functional sensitivity of < or = 0.01 mIU L-1 for optimal titration of L-T4 suppressive therapy, especially in patients with thyroid cancer. If, however, only a second generation TSH assay is available, additional TRH testing allows a more careful titration of suppressive thyroxine therapy.

Administration, Intranasal↗
PubMed2002

Are drivers more likely to injure their right or left foot in a frontal car crash: a crash and biomechanical investigation.

In this study we hypothesized that for frontal crashes, the driver was more likely to sustain foot injury than the front seated passenger and the right foot was more likely to be injured than the left because the driver's right foot was positioned in dorsiflexion and eversion during the crash and less able to tolerate crash forces. Seventeen CIREN frontal crashes were studied to document the circumstances and resulting foot injuries. NASS data was sampled to determine frequencies of injury to foot side and occupant position. Biomechanically, matched pairs of cadaveric feet were tested in compression with one in dorsiflexion, and the other, dorsiflexion, and eversion. Results showed that drivers were more likely than passengers to sustain a foot or ankle injury and this was almost exclusively due to a higher frequency of right foot injuries in drivers. Braking, with significant toepan intrusion, was associated with an increase in both right and left foot injuries in drivers. Biomechanically, 9 of 15 pairs tested provided useable data. There was a significant decrease in load to failure between specimens forced into dorsiflexion and eversion (mean, 4107 N, sd = 1630 N) compared with dorsiflexion alone (mean, 6468 N, sd = 2435 N, p = 0.001). The majority (16 of 17) of foot injuries in the CIREN cases were to drivers of which 13 injured their right foot and ankle. An implication of this work is that if thresholds based on data from dorsiflexion and compression loading are used to predict foot and ankle injury in frontal crashes they may not represent that population of drivers who are braking at the time of the crash and could suffer injuries at forces lower than current threshold values.

Accidents, Traffic↗
PubMed2001

Pairing interactions and Gibbs adsorption at the liquid bi-in surface: a resonant X-ray reflectivity study.

Resonant x-ray reflectivity measurements from the surface of liquid Bi(22)In(78) find only a modest surface Bi enhancement, with 35 at. % Bi in the first atomic layer. This is in contrast to the Gibbs adsorption in all liquid alloys studied to date, which show surface segregation of a complete monolayer of the low surface tension component. This suggests that surface adsorption in Bi-In is dominated by attractive interactions that increase the number of Bi-In neighbors at the surface. These are the first measurements in which resonant x-ray scattering has been used to quantify compositional changes induced at a liquid alloy surface.

Journal Article↗
PubMed2001

TSH-controlled L-thyroxine therapy reduces cholesterol levels and clinical symptoms in subclinical hypothyroidism: a double blind, placebo-controlled trial (Basel Thyroid Study).

This study evaluated the effect of physiological, TSH-guided, L-thyroxine treatment on serum lipids and clinical symptoms in patients with subclinical hypothyroidism. Sixty-six women with proven subclinical hypothyroidism (TSH, 11.7 +/- 0.8 mIU/liter) were randomly assigned to receive L-thyroxine or placebo for 48 wk. Individual L-thyroxine replacement (mean dose, 85.5 +/- 4.3 microg/d) was performed based on blinded TSH monitoring, resulting in euthyroid TSH levels (3.1 +/- 0.3 mIU/liter). Lipid concentrations and clinical scores were measured before and after treatment. Sixty-three of 66 patients completed the study. In the L-thyroxine group (n = 31) total cholesterol and low density lipoprotein cholesterol were significantly reduced [-0.24 mmol/liter, 3.8% (P = 0.015) and -0.33 mmol/liter, 8.2% (P = 0.004), respectively]. Low density lipoprotein cholesterol decrease was more pronounced in patients with TSH levels greater than 12 mIU/liter or elevated low density lipoprotein cholesterol levels at baseline. A significant decrease in apolipoprotein B-100 concentrations was observed (P = 0.037), whereas high density lipoprotein cholesterol, triglycerides, apolipoprotein AI, and lipoprotein(a) levels remained unchanged. Two clinical scores assessing symptoms and signs of hypothyroidism (Billewicz and Zulewski scores) improved significantly (P = 0.02). This is the first double blind study to show that physiological L-thyroxine replacement in patients with subclinical hypothyroidism has a beneficial effect on low density lipoprotein cholesterol levels and clinical symptoms of hypothyroidism. An important risk reduction of cardiovascular mortality of 9-31% can be estimated from the observed improvement in low density lipoprotein cholesterol.

Cholesterol↗
PubMed2000

Conventionally fractionated stereotactic radiotherapy (FSRT) for acoustic neuromas.

PURPOSE: Analysis of local tumor control and functional outcome following conventionally fractionated stereotactic radiotherapy (FSRT) for acoustic neuromas. PATIENTS AND METHODS: From 11/1989 to 9/1999 51 patients with acoustic neuromas have been treated by FSRT. Mean total dose was 57.6 +/- 2.5 Gy. Forty-two patients have been followed for at least 12 months and were subject of an outcome analysis. Mean follow-up was 42 months. We analyzed local control, hearing preservation, and facial and trigeminal nerve functional preservation. We evaluated influences of tumor size, age, and association with neurofibromatosis Type 2 (NF2) on outcome and treatment related toxicity. RESULTS: Actuarial 2- and 5-year tumor control rates were 100% and 97.7%, respectively. Actuarial useful hearing preservation rate was 85% at 2 and 5 years. New hearing loss was diagnosed in 4 NF2 patients. Pretreatment normal facial nerve function was preserved in all cases. Two cases of new or impaired trigeminal nerve dysesthesia required medication. No other cranial nerve deficit was observed. In Patients without NF2 tumor size or age had no influence on tumor control and cranial nerve toxicity. Diagnosis of NF2 was associated with higher risk of hearing impairment (p = 0.0002), the hearing preservation rate in this subgroup was 60%. CONCLUSION: FSRT has been shown to be an effective means of local tumor control. Excellent hearing preservation rates and 5th and 7th nerve functional preservation rates were achieved. The results support the conclusion that FSRT can be recommended to patients with acoustic neuromas where special attention has to be taken to preserve useful hearing and normal cranial nerve function. For NF2 patients, FSRT may be the treatment of choice with superior functional outcome compared to treatment alternatives.

Actuarial Analysis↗
PubMed2000

Increased CSF levels of nerve growth factor in patients with Alzheimer's disease.

The authors quantitated CSF levels of nerve growth factor (NGF) in patients with AD, nondemented control subjects (CTR), and age-matched patients with major depression (DE). CSF levels of NGF were markedly higher in the AD group than in both the CTR and DE groups (p < 0.01 and p < 0.001). Increased CSF levels of NGF in AD patients may reflect reported accumulation of NGF in the AD brain and may constitute a candidate marker for clinical diagnosis and therapeutic monitoring.

Adult↗
PubMed2000

ETS1 lowers capillary endothelial cell density at confluence and induces the expression of VE-cadherin.

Ets1 is a transcription factor expressed in endothelial cells during angiogenesis but its target genes and function in blood vessel formation are still unknown. We have over-expressed Ets1 as a tagged protein in brain capillary endothelial cells and in 3T3 fibroblasts using a retroviral vector. Over-expression of Ets1 reduced by nearly half cell density at confluence of endothelials but not of fibroblasts. As density at confluence is controlled in part by cadherins, this growth arrest could be due to the up-regulation of these cell contact molecules. Indeed, Ets1 increased the expression of the endothelial-specific VE-cadherin without affecting N-cadherin expression levels. In parallel, both a dominant negative mutant of Ets members and an Ets1 anti-sense oligonucleotide inhibited VE-cadherin expression in endothelial cells. Ets1 bound to two Ets-binding sites located in the proximal region of the VE-cadherin promoter. Mutation of these sites abolished Ets1-induced transactivation of the promoter. The present work is the first demonstration of a function of Ets1 in the regulation of a specific endothelial marker based on its endogenous gene and protein expression.

Animals↗
PubMed2000

[Aphasia research and speech localization in the brain].

Aphasia research has become an acknowledged branch of modern cognitive neuropsychology research whose aim is to explore more fully the structures of knowledge and of cerebral processes which might both be affected in patients with aphasia. Up to the second half of this century, a model based on a specific cerebral localisation of language processes had emerged based on brain localisation research by Broca and Wernicke (among others). New modern neuroimaging techniques, however, such as computed tomography and magnetic resonance imaging (MRI), but also functional imaging modalities such as positron emission tomography or functional MRI, have modified these concepts. It emerges that in comprehension as well as in production of language, not only a few well defined centres are responsible for the activity, but there is a synchronised activity in large neuronal networks connecting various regions located both in the cortex and in the deep subcortical structures; today, this activity can be demonstrated best in a non-invasive and reproducible way with functional MRI.

Aphasia↗
PubMed2000

Cataract incidence after total-body irradiation.

PURPOSE: The aim of this retrospective study was to evaluate cataract incidence in a homogeneously-treated group of patients after total-body irradiation (TBI) followed by autologous bone marrow transplantation or peripheral blood stem cell transplantation. METHODS AND MATERIALS: Between 1982 and 1994, a total of 260 patients received either autologous bone marrow or blood stem cell transplantation for hematological malignancy at the University of Heidelberg. Two hundred nine of these patients received TBI in our hospital. Radiotherapy was applied as hyperfractionated TBI, with a median dose of 14.4 Gy in 12 fractions over 4 days. Minimum time between fractions was 4 h. Photons with an energy of 23 MeV were used with a dose rate of 7-18 cGy/min. Ninety-six of the 209 irradiated patients were still alive in 1996; 86 of these patients (52 men, 33 women) answered a questionnaire and could be examined ophthalmologically. The median age at time of TBI was 38.5 years, with a range of 15-59 years. RESULTS: The median follow-up is now 5.8 years, with a range of 1.7-13 years. Cataract occurred in 28/85 patients (32.9%) after a median of 47 months (1-104 months). In 6 of 28 patients who developed a cataract, surgery of the cataract was performed. Whole-brain irradiation prior to TBI had been performed more often in the group of patients developing cataract (14.3%) versus 10.7% in the group of patients without cataract. However, there was no statistical difference (Chi-square, p>0.05). CONCLUSION: Cataract is a common side effect of TBI. Cataract incidence found in our patients is comparable to results of other centers using a fractionated regimen for TBI. To assess the incidence of cataract after TBI, a long-term follow-up is required.

Adult↗
PubMed2000

Primary colonic lymphoma.

BACKGROUND AND OBJECTIVES: The colon is a rare location for gastrointestinal non-Hodgkin's lymphoma (NHL). This study was undertaken to identify risk factors, presentation, treatment, and prognosis for primary colonic lymphoma (PCL) through review of a large tertiary care hospital system experience. METHODS: A retrospective review of all patients with colonic malignancy and NHL was performed using pathology and cancer registry databases from January 1989 to December 1998. Criteria for inclusion were no evidence of extraperitoneal disease, no leukemic or lymphomatous abnormalities in the blood, and disease confined to the colon. RESULTS: Seven patients met the inclusion criteria (4 male, 3 female; 33-72 years). They represented 1.4% of all NHL, 14% of gastrointestinal NHL and 0.9% of all colonic malignancies diagnosed during this period. Three of the patients had positive serology for human immunodeficiency virus; one was taking steroids chronically for Addison disease. The most common presentation was nonspecific abdominal pain. The lack of specific symptoms delayed diagnosis from 1-12 months. All patients underwent laparotomy with resection. The most common tumor location was the cecum (5/7, 71%). Regional lymph nodes were affected in all but 1 patient. All tumors were B-cell lymphomas (5 small noncleaved cell, 2 large cell). Six of 7 patients received adjuvant chemotherapy. Of the 6 patients available for follow-up four remain alive (12, 19, 23, and 25 months after diagnosis). In both patients who died the disease recurred diffusely. CONCLUSIONS: The colon is a rare location for NHL. Immunosuppression is the most common risk factor. Patients' frequently present with non-specific abdominal pain, this leads to lengthy delays in diagnosis. Most of these tumors are located in the cecal area. Surgery is the most widely utilized form of therapy. Although adjuvant therapy is frequently utilized, its' impact on survival is unclear.

Academic Medical Centers↗
PubMed2000

Anorectal Disease.

Most symptomatic internal hemorrhoids, grade 1 through 3, can be treated successfully with office-based procedures. Anorectal suppurative diseases must be treated surgically. Control of sepsis with subsequent fistula surgery as necessary is the goal. New nonoperative methods of anal fissure therapy are directed at reducing anal sphincter pressures. These methods have shown significant reduction in the need for sphincterotomy--a proven surgical technique with some risk of impaired continence. Surgery, using an advancement flap and partial internal sphincterotomy, remains the primary treatment for anal stenosis. Solitary rectal ulcer remains a difficult problem to manage medically and surgically. Multiple surgical techniques can effectively treat rectal prolapse. A minimal technique using Silastic wrap (Wright Medical Technologies; Arlington, TX), perineal resection (Altemeier procedure), and sigmoidectomy-rectopexy, or Ripstein suspension, has been the most favored method in selected patients.

Journal Article↗
PubMed2000

Interpreting complex urinary patterns with MDI LABLINK: a statistical evaluation.

The measurement of urinary marker proteins is not a generally accepted laboratory practice because the results are difficult to interpret. MDI-LABLINK is software for classifying patterns of specific urinary marker proteins. The interpretations are completely user definable thanks to a specific 'pattern definition database'. Our interpretation set is based on Hofmann and Guder's work in measuring and interpreting single urinary proteins. We include additional marker proteins in order to adapt Boesken's SDS-PAGE classification. During the last 3 years, 1905 patterns were fully differentiated and identically interpreted. Firstly, the samples were classified into three patterns: normal (25.8%), predominantly glomerular (27.2%, selective, unselective, mixed, and with additional tubular proteins) and predominantly tubular (36.9%, complete/incomplete form, with additional glomerular proteins); 8.9% showed postrenal proteinuria. Secondly, glomerular selectivity measured by using urinary transferrin/IgG ratio alone correlates well with the established SI index (the ratio between IgG and transferrin clearances). Thirdly, the creatinine concentration substantiates the validity of the sample. The quality of the preanalytical phase can be improved through the ongoing education of the medical staff. Finally, measurement of urinary albumin and alpha-1-microglobulin is mandatory where kidney disease is suspected, has to be ruled out, or requires close monitoring, even when the total protein concentration is normal.

Adolescent↗
PubMed2000

Increased cerebrospinal fluid levels of neurotrophin 3 (NT-3) in elderly patients with major depression.

Neurotrophin 3 (NT-3) is a member of the neurotrophin gene family which supports the survival of specific neurons. NT-3 was shown to prevent the death of adult central noradrenergic neurons in vivo, a neuronal population which is associated with the pathophysiology of major depression. We quantitated CSF levels of NT-3 in elderly patients with major depression (DE) and compared them to patients with Alzheimer's disease (AD), and mentally healthy control subjects (CTR). CSF levels of NT-3 were markedly and significantly elevated in the DE group, as compared to either the AD or the CTR group (P < 0.01, and P < 0.001, respectively). In terms of diagnostic accuracy, measurement of NT-3 levels in DE resulted in 73.9% sensitivity, and 89.7% specificity. Increased CSF levels of NT-3 may indicate a disturbance of the central noradrenergic system in patients with DE. NT-3 may constitute a biochemical candidate marker for clinical diagnosis and for the evaluation of therapeutic strategies in DE.

Adult↗