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J Hüsing

Publications and source records attributed to J Hüsing.

At least 19 recordsLinked to original sources
PubMed2004

How reliable is the allopurinol load in detecting carriers for ornithine transcarbamylase deficiency?

The allopurinol test aims to distinguish carriers and noncarriers for ornithine transcarbamylase (OTC) deficiency. We have evaluated the reliability of the test in at-risk females of known genotype. Results based on urine orotidine and/or orotic acid measurement were compared in terms of sensitivity and specificity. Retrospectively, we analysed the results of allopurinol tests in 42 women (22 confirmed heterozygotes and 20 noncarriers) from 23 pedigrees at risk of being carriers for OTC deficiency. Using a cut-off of 2 standard deviations above the mean of controls, the highest sensitivity (91%) was given by orotidine alone or in combination with orotic acid, but specificity was only 70% and 65%, respectively. We conclude that the value of the allopurinol test for detecting OTC carriers in at-risk females is limited. This needs to be recognized when counselling families. The test still has a role as a safe, quick, noninvasive screen of individuals at risk, but test results in possible carriers should be interpreted with caution. In the absence of other supportive evidence, confirmation by mutation analysis is required.

Adult↗
PubMed2004

Predictive value of mechanomyography and accelerometry for pulmonary function in partially paralyzed volunteers.

BACKGROUND: Accelerometry (ACM) of adductor pollicis muscle has been used for monitoring of neuromuscular blockade but its validity compared with the gold standard, mechanomyography (MMG), has been questioned. During neuromuscular blockade we compared these methods and we assessed pulmonary function. METHODS: In awake partially paralyzed volunteers we spirometrically assessed pulmonary function every 5 min until recovery. Rocuronium (0.01 mg kg(-1) + 2-10 microg kg(-1) min(-1)) was administered to maintain train-of-four (TOF)-ratios (assessed every 15 s) of approximately 0.5 and 0.8 over a period of more than 5 min. The TOF-ratio associated with 'acceptable' pulmonary recovery [forced vital capacity (FVC) and forced inspiratory volume in 1 s (FIV1) of > or =90% of baseline] was calculated using a linear regression model. During 5-min periods of repetitive nerve stimulation we compared the squared residuals of the FVC and FIV1 estimates from TOFACM vs. TOFMMG, and compared variance of values derived from ACM and MMG using Wilcoxon's test. RESULTS: Limits of agreement of TOF-ratio derived from ACM and MMG were wide [0.15+/-0.016 (SD)], and variability of TOFACM exceeded that of TOFMMG[variance: 77+/-105 vs. 51+/-55% (P<0.01)]. Calculated TOF(ACM) and TOFMMG ratios of 0.56 (0.22-0.71) [mean (95%CI) and 0.6 (0.28-0.74)], respectively, predict 'acceptable' (90%) recovery of FVC while FIV1 remains impaired until TOF-ratios of 0.91 (0.82-1.07) and 0.95 (0.82-1.18), respectively. In turn, TOFMMG (TOFACM) of unity predicted 'acceptable' recovery of FVC and FIV1 in 94 (93) % and 68 (73) % of measurements, respectively. CONCLUSIONS: Accelerometry predicts effects of relaxation on pulmonary function as valid as the gold standard mechanomyography. We recommend that recovery of TOF ratio to 0.9-1.0 should be used as an indication of sufficient neuromuscular recovery in daily practice.

Adult↗
PubMed2003

Software packages for quantitative microarray-based gene expression analysis.

Microarray technology enables researchers to investigate the expression of several thousand genes simultaneously. The whole transcriptional response of these genes in normal cells or tissue, in disease condition, as an response to biological, genetical or chemical stimuli or during normal biological processes such as cell cycle or embryonic development can be investigated. This leads to a huge amount of data, from which the relevant information has to be extracted by statistical and computational methods. Several software packages for the analysis of gene expression data are available, both commercially and freely. They differ particularly with regard to the implemented analytical methods, the graphical display and the manageability. In this paper the commercial software packages arraySCOUT, GeneSpring and Spotfire DecisionSite for Functional Genomics are compared and their applicability for analysis of gene expression data is studied. Small artificial and application test datasets are used to compare the computational results of the software packages. As far as possible results are verified with standard statistical software package SAS.

Algorithms↗
PubMed2002

Monitoring retinal function in neovascular maculopathy using multifocal electroretinography - early and long-term correlation with clinical findings.

PURPOSE: To objectively investigate and longitudinally monitor retinal function in patients with choroidal neovascularization (CNV) due to exudative age-related macular degeneration (AMD) and myopia using multifocal electroretinography (mfERG). METHODS: Patients with classic and occult subfoveal CNV secondary either to AMD or to myopia were enrolled in the study. The mfERGs were performed at the beginning of the study and every 3 months subsequently during a follow-up period of 15 months. In addition, standardized visual acuity testing, ophthalmologic examinations, color fundus photographs and fluorescein angiography were performed. The mfERG records were derived with the VERIS-System (Electro-Diagnostic Imaging, San Mateo, Calif., USA); 103 locations within the central 50 degrees in diameter were stimulated concurrently by means of the m-sequence technique. Fixation stability was monitored throughout the recording session with an infrared eye monitoring system (VERIS Refractor/Camera unit). The first-order response component was extracted for each stimulated retinal location. The response densities of the first-order kernel were evaluated as a function of eccentricity from the center (ring 1) to the periphery of the stimulated area (ring 6). The results were compared to those derived from age-matched normal control groups. For each patient mfERG responses measured on follow-up visits were compared to each other to evaluate and monitor changes in retinal function. These changes were tested for correlation with those observed in other clinical and electroretinographic findings. Statistical analysis was performed using the Pearson coefficient. RESULTS: Subfoveal neovascular maculopathy was associated with a reduction in response density most prominent within the central 5 degrees over the area affected by CNV detected either at the beginning of the study or at the follow-up recordings. During the follow-up period patients 1 and 4 showed stabilization or a slight increase in response densities over the neovascular lesion-complex and a corresponding stabilization or slight increase in visual acuity accompanied by a decrease in the activity of the neovascular lesion as determined by fluorescein angiography. Patient 2 revealed an increase in response density correlating with an increase in visual acuity and decrease in lesion size. In the contralateral eye of this patient the response density dropped in the area of new subfoveal CNV. In patient 3 continuous progression of the disease was documented by fluorescein angiography and visual acuity. It correlated well with a continuous decrease in retinal response densities during the follow-up. CONCLUSIONS: Objective monitoring of retinal function and correlation with morphological and psychophysical findings was at least in part possible in patients suffering from AMD and myopia. In all of four patients whose subfoveal CNV was documented by fluorescein angiography. Response densities were reduced particularly in the central 5 degrees and in visual acuity. The mfERG data showed a moderate to high statistical correlation with visual function as measured by visual acuity. On the other hand, the greatest linear dimension of the lesion size showed only a weak to moderate statistical correlation with both the response densities of the mfERG and the visual acuity. We conclude that the size of the CNV complex does not represent an accurate measure of retinal function in neovascular maculopathy. The good correlation of the mfERG data with visual acuity suggests that it may serve for objective assessment of retinal function, of the areas overlying the CNV. It shows potential as a valuable tool for longitudinal monitoring of AMD patients.

Aged↗
PubMed2002

Optimal rocuronium dose for intubation during inhalation induction with sevoflurane in children.

BACKGROUND: We studied 120 children aged 2-7 yr in a prospective, randomized, assessor-blinded fashion to define the optimal rocuronium dose which provides a 95% probability of acceptable intubation conditions (ED95TI) during inhalation induction with sevoflurane. METHODS: After inhalation induction with 8% sevoflurane in 60% nitrous oxide and 40% oxygen, and loss of the eyelash reflex, we administered rocuronium (0.1, 0.15, 0.22, 0.3, or 0.6 mg kg-1) or placebo. We quantified neuromuscular function by stimulation of the ulnar nerve at 0.1 Hz to produce contraction of the adductor pollicis muscle using accelerometry. Intubation conditions were assessed 2 min after test drug injection. The optimal rocuronium dose was defined as the lowest dose, which allowed acceptable intubation conditions in 95% of children (ED95TI). RESULTS: Two minutes after injection of placebo or rocuronium, intubation conditions were acceptable in 35, 45, 80, 90, 95, and 100% of children, respectively. Rocuronium 0.07 [CI 0.02-0.11], 0.24 [0.19-0.31], and 0.29 [0.23-0.38] mg kg-1 provided 50, 90, and 95% probability of acceptable intubating conditions. When thumb acceleration was depressed by 50% or more, intubating conditions were considered acceptable in 97% of children. Recovery of the train-of-four ratio to 0.8 averaged 12 (7), 16 (7), 24 (7), 24 (8), and 50 (22) min after the respective dose of rocuronium. CONCLUSIONS: During inhalation induction with 8% sevoflurane in 60% nitrous oxide, rocuronium 0.29 mg kg-1 (ED95) optimizes intubation conditions for surgery of short duration.

Androstanols↗
PubMed2001

A scheme for a dose-escalation study when the event is lagged.

Classical designs for clinical phase I trials assume that information about a dose-limiting event (DLE) is available for all the included patients, or advise not to treat new patients until the information is present. If a DLE occurs after a lag, however, information at the current time might not be sufficient to make clear-cut decisions according to these designs. In particular, if new patients are available, it is not clear whether to include them in the trial. We suggest a rule that decides on the accrual of each individual eligible patient. Simulation studies are presented that indicate an advantage over the standard 'three-at-once' design in the length of the study.

Boron Neutron Capture Therapy↗
PubMed2001

Procalcitonin for accurate detection of infection in haemodialysis.

BACKGROUND: Infection results in considerable morbidity and mortality in haemodialysis patients. Diagnosis of infection can be difficult because currently applied laboratory parameters may be non-specifically altered due to uraemia or haemodialysis (HD). This study investigated the diagnostic value and kinetics of serum procalcitonin (PCT), a low-molecular-weight protein, in patients receiving intermittent HD. METHODS: Sixty-eight patients receiving intermittent HD for end-stage renal disease (n=48) or acute renal failure (n=20) were prospectively studied, 47 treated with high-flux and 21 with low-flux membranes. Of 36 patients with severe infections or sepsis, 27 were treated with high-flux and nine with low-flux membranes. WBC, serum PCT and C-reactive protein (CRP) concentrations were measured immediately before HD, and PCT repeatedly during the following 48 h. RESULTS: When determined immediately before HD, PCT demonstrated a sensitivity of 89%, a specificity of 81%, and positive and negative predictive values of 84 and 87%, indicating severe infection or sepsis. These levels were higher than the respective values for CRP (89, 48, 68 and 78%) and WBC (58, 75, 71 and 59%). After 4 h of HD with high-flux membranes, PCT decreased significantly to 83+/-25% and did not return to predialysis concentrations before 48 h. This decrease in serum PCT resulted in markedly reduced sensitivity (65%) and negative predictive value (54%). In contrast, no marked change in PCT concentration occurred during or after HD with low-flux membranes. CONCLUSION: Serum PCT is an accurate indicator of severe infection and sepsis in patients receiving intermittent HD. High-flux membranes substantially decrease PCT. When utilizing high flux membranes, serum PCT concentrations should be determined prior to the start of HD.

Acute Kidney Injury↗
PubMed2001

Early detection of prostate cancer in Germany: a study using digital rectal examination and 4.0 ng/ml prostate-specific antigen as cutoff.

OBJECTIVE: While international screening studies for prostate cancer are by now almost reaching the estimated number of recruitments mandatory for the necessary power to investigate an effect on mortality of prostate cancer, no statistical figures on the detection of prostate cancer in Germany - apart from historical data before the use of prostate-specific antigen (PSA) are available. In order to generate a database and to investigate the diagnostic efficacy of the primarily practice-based urological care system, a case finding study designed as a nationwide longitudinal early detection trial was initiated. METHODS: In one week in November 1997, 963 urologists prospectively examined 11,644 men between 45 and 75 years of age by digital rectal examination (DRE) and PSA with 4.0 ng/ml as cutoff. Data of family history and physical examination were collected by questionnaire. At this time participants were not aware of their PSA value. PSA was determined in the study center. Indication for sextant biopsy was a PSA value above 4.0 ng/ml or a suspicious lesion on DRE. Any indicated biopsy not performed had to be clarified. In a second questionnaire results of prostate biopsy, treatment and tumor status were documented. RESULTS: The mean age of the study population was 62 years (median 62). The PSA median was 1.4 ng/ml with 82.8% presenting with < 4.0 ng/ml, 12.8% with 4-10 ng/ml and 4.4% with >10 ng/ml. From 1,115 men (47.7%) biopsied, 262 cancers were detected resulting in a detection rate of 23.5%. While 399 men refused biopsy, further investigation was not recommended in 387 men by their urologist, because prostatitis or benign hyperplasia was thought to be the cause for elevated PSA. From the 143 patients undergoing radical prostatectomy, 93 (65%) cancers were organ confined. T(1c) cancers with elevated PSA > 10 ng/ml could be treated with curative intent in 44% only. The positive predictive value (PPV) was estimated to be 16% for DRE alone (14/90), 17% for PSA alone (143/819) and 51% for the combination of both (105/206). In that cohort, use of age-adjusted PSA values and PSA density increased the PPV of PSA testing nonsignificantly. CONCLUSIONS: Significant higher PPV indicated that utilizing a combination of both DRE and PSA is most effective in the early detection of prostate cancer. Unnecessary biopsies can be avoided using either age-adjusted PSA value or PSA density, but the PPV is not significantly changed and potentially curable cancer is missed in up to 25%. Given the substantial variability of the diagnostic approach despite the study design, uniform guidelines are necessary to ensure countrywide sufficient screening.

Aged↗
PubMed2000

Interaction of the G protein beta 3 subunit T825 allele and the IRS-1 Arg972 variant in type 2 diabetes.

BACKGROUND: Type 2 diabetes mellitus is a common late-onset disease with a strong genetic component. It is characterized by insulin resistance which results from alterations in insulin signal transduction. The G protein beta 3 subunit 825T allele was recently found to be associated with hypertension and obesity which makes it a sensible candidate gene for type 2 diabetes. METHODS: In a case-control study on 320 male patients and 962 male healthy controls we investigated the association of two candidate genes with diabetes, i.e. (i) the GNB3 825T allele, associated with a G protein beta 3 subunit splice variant and enhanced intracellular signal transduction, and (ii) the insulin receptor substrate-1 (IRS-1) 972Arg variant, which encodes a protein variant associated with cellular insulin resistance. RESULTS: The GNB3 825T allele and the IRS-1 972Arg variant were significantly associated with diabetes (odds ratios for either variant 1.4 1.8). Odds ratios were 3 4 in males carrying both alleles. CONCLUSIONS: The results document an association of a hypertension susceptibility gene with type 2 diabetes which may partially explain the frequent coexistence of both disorders.

Adult↗
PubMed2000

[Early detection of prostatic carcinoma in urologic practice with digital rectal examination and prostate-specific antigen. Early Detection Project Group].

For the early detection of prostate cancer, a patient should undergo digital rectal examination (DRE) and PSA investigation. Follow-up of increased PSA levels detects nearly 80% of cancers. Positive predictive value of suspicious DRE and PSA is about 50%. Whereas in the first evaluation of this case-finding trial about 70% of the patients had organ-confined cancers, nearly all of the detected cancers in the follow-up investigation were organ confined. The increased number of organ-confined cancers detected in early periodical examinations can lead to a reduction of mortality and morbidity from prostate cancer.

Adult↗
PubMed2000

Reduced risk of persisting cytomegalovirus pp65 antigenemia and cytomegalovirus interstitial pneumonia following allogeneic PBSCT.

In order to evaluate the risk of cytomegalovirus (CMV) associated disease after allogeneic stem cell transplantation (SCT), 158 consecutive patients at risk for infection were analyzed. BMT was performed in 101 patients and peripheral blood stem cell transplantation (PBSCT) in 57 patients. CMV antigenemia was found in 57 cases (56%) after BMT and 27 cases (47%) after PBSCT, respectively. CMV antigenemia resistant to a 14-day course of GCV was found in 26 patients (26%) after BMT but in only four patients (7%) after PBSCT (P < 0.01). Eighteen patients (11%) developed CMV disease, 14 post BMT and four post PBSCT. Lethal CMV-related interstitial pneumonia (CMV-IP) occurred in 13 cases of whom 12 patients were bone marrow recipients (P = 0.04). The subgroup of seronegative patients with a CMV seropositive donor had a significantly lower risk of developing CMV antigenemia, GCV-resistant CMV antigenemia (P < 0.01) and CMV-related disease (P = 0.01). In conclusion, the incidence of persistent CMV antigenemia and CMV-IP was significantly reduced when allogeneic transplantation was performed with peripheral blood stem cells instead of bone marrow. These findings suggest that our previous in vitro data on improved immune reconstitution after allogeneic PBSCT as compared to allogeneic BMT have clinical relevance.

Adolescent↗
PubMed2000

Interaction of the ACE D allele and the GNB3 825T allele in myocardial infarction.

In polygenetic disorders, such as ischemic heart disease, the investigation of gene-gene interactions rather than determination of single gene effects is crucial to better understand the contribution of genetic factors. The 825T allele of the G-protein ss(3)-subunit gene (GNB3) associated with enhanced G-protein signaling is a candidate to interact with the angiotensin-converting enzyme (ACE) deletion/insertion (D/I) polymorphism to increase the risk for myocardial infarction (MI). The ACE D:/I variant affects the renin-angiotensin system hormones that activate G-protein-coupled receptors. Genotyping at the ACE and GNB3 loci was performed on 585 patients with coronary artery disease with (n=270) or without (n=315) previous MI. Logistic regression analysis demonstrated a significant interaction between the ACE D: allele and the GNB3 825T allele (P<0.001). The odds ratio for MI, associated with the 825T allele, was not increased in the presence of the ACE II genotype (OR 0.5; P=0.09) but was significantly higher in 825T allele carriers with the ACE DI genotype (OR 1.9; P=0.01) and further increased in individuals with the ACE DD genotype (OR 2.4; P=0.02). The highest odds ratio was found in homozygous 825T allele carriers with the ACE DD genotype (OR 7.5; P=0.006). Our data suggest a significant interaction of the GNB3 825T allele with the ACE D allele in MI. These hypothesis-generating data may justify larger prospective studies.

Aged↗
PubMed1999

Influence of sodium butyrate on the induction of radiation-induced chromosomal aberrations and sister chromatid exchanges in Chinese hamster ovary (CHO) cells.

CHO cells were pre-treated with sodium butyrate (SB) for 24 h and then X-irradiated in G1. Metaphases were scored for the induction of chromosomal aberrations and sister chromatid exchanges (SCEs). The data were compared with those obtained after irradiation of cells not pre-treated with SB and showed that SB has different effects on the endpoints examined. The frequencies of dicentric chromosomes were elevated and of small acentric rings (double minutes, DMs) reduced. These results are discussed to be a consequence of conformational changes in hyperacetylated chromatin which could lead to more interchromosomal and to less intrachromosomal exchanges. SB itself induces a few SCEs but suppresses the induction of SCEs by X-rays. We assume that a minor part of radiation induced SCEs are 'false' resulting from structural chromosomal aberrations, such as inversions, induced in G1. Inversions are the symmetrical counterparts of DMs. If inversions are suppressed by SB treatment to a similar extent as DMs a small reduction of SCEs by SB can be expected.

Animals↗
PubMed1999

[Early recognition of prostate carcinoma. Initial results of a prospective multicenter study in Germany. Project Group for Early Detection DGU-BDU Laboratory diagnosis Professional Circle].

To compare the efficacy of digital rectal examination (DRE) and serum prostate specific antigen (PSA) in early detection of prostate cancer, we initiated a prospective multicenter screening trial. In 12,542 men choosen at random with a mean age of 62 (+/- 7.5) a suspect DRE or a PSA level > 4.0 ng/ml was found in 2343 (20%). Of the presently performed 744 biopsies, 157 revealed diagnosis of prostate cancer. Although further biopsies as well as the follow up of the 12,542 men are still missing, combination of DRE and PSA value > 4.0 ng/ml appears to be superior to DRE alone with a positive predictive value of 50% versus 19% in early detection of prostate cancer.

Aged↗
PubMed1998

Impact of resting and ischemic blood flow on infarct probability in ischemic preconditioning--a new approach to infarct size-blood flow data by logistic regression.

The linear regression analysis of infarct size (IS) v ischemic myocardial blood flow (MBF) does not account for the heterogeneity of MBF and infarcted tissue; moreover, it cannot assess a blood flow threshold for infarction (MBFT) accurately, as with ischemic preconditioning (IP) the close relationship between ischemic MBF and IS otherwise observed is lost. Finally, the impact of resting blood flow on myocardial infarction cannot be considered in such analysis. Therefore, in a retrospective data analysis of 32 enflurane-anaesthetized swine undergoing 90 min severe ischemia and 120 min reperfusion without (CON, n = 12) or with IP induced by either 3 (IP3, n = 8) or 10 min ischemia (IP10, n = 12) and 15 min reperfusion, a MBFT was assessed by logistic regression (LR) in individual tissue pieces. MBFT was arbitrarily defined as that ischemic MBF (microspheres) at which infarct probability was 0.2, derived from the ratio of infarcted (n = 141, TTC) to all tissue samples (n = 684). The duration of the preconditioning ischemia and MBF both at rest and during the sustained ischemia were significant predictors of infarct probability. Ischemic MBFT at an infarct probability of 0.2, was 0.089 +/- 0.023 ml/min/g in CON. MBFT was decreased to 0.051 +/- 0.03 ml/min/g with IP3 (P < 0.05 v CON) and further to 0.004 +/- 0.037 ml/min/g with IP10 (P < 0.05 v CON, IP3). Corresponding to the leftward shift of MBFT, the relationships between infarct probability and MBF were shifted in parallel by IP with no change in their slopes.

Animals↗
PubMedDate not supplied

[Small premature infants do not tolerate axillary temperature measurement any better than rectal measurement. Study of the effect of axillary and rectal temperature measurement on vital parameters and cerebral hemodynamics and oxygenation].

BACKGROUND: Aim of this study was to assess, by use of monitoring parameters and near infrared spectroscopy (NIRS), whether premature infants tolerate axillary temperature measurement better than rectal. METHODS: Twenty-one infants were studied. Birth weight was 540-1680 g (median 840 g), weight at the time of investigation 470-1500 g (Median 920 g), gestational age 24-31 weeks (median 29 weeks), age at time of investigation 4-25 days (median 11 days). Four pairs of axillary/rectal temperatures were taken in every infant. Heart rate and oxygen saturation were monitored. Using NIRS cerebral oxygenated and deoxygenated hemoglobin were measured and total cerebral hemoglobin and the cerebral oxygenation index were calculated. RESULTS: Mean heart rate increased slightly but significantly from baseline during axillary and rectal temperature measurement (axillary: +6/min (+/- 7); p < 0.0001; rectal: +4/min (+/- 6); p < 0.0001). Peak increase in heart rate was significantly higher during axillary than during rectal temperature measurement (axillary: +18/min (+/- 10); rectal: +14/min (+/- 8); axillary versus rectal: p = 0.02). There was no difference in the number of measurements during which oxygen saturation dropped intermittently below 88% (rectal: 21% of measurements; axillary: 20% of measurements). NIRS parameters were not significantly different between axillary and rectal measurements: cerebral oxygenated hemoglobin and the oxygenation index showed a decrease in cerebral oxygenation during both, axillary and rectal measurement. CONCLUSIONS: Axillary temperature measurement is not better tolerated than rectal in premature infants.

Axilla↗