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M Vogel

Publications and source records attributed to M Vogel.

At least 199 records · Page 11Linked to original sources
PubMed1996

Scombroid poisoning.

Scombroid poisoning is described in the literature as a toxic poisoning caused by ingestion of certain dark meat fish undergoing bacterial decomposition. Poisoning results from the ingestion of a heat-stable toxin. We describe the case of a man who presented to the emergency department several hours after eating tuna steak with evidence of scombroid poisoning that was associated with loss of vision and atrial tachycardia with block. All signs and symptoms resolved after treatment for scombroid poisoning.

Acute Disease↗
PubMed1996

Morphometric techniques in the evaluation of pulmonary vascular changes due to congenital heart disease.

Open lung biopsy is performed in patients with congenital heart disease to determine the suitability for surgical correction. Controversy exists as to whether arterial density can be graded with certainty. We studied the influence on the grading (Heath-Edwards) of two morphometric techniques. Lung tissue from 14 controls and biopsy specimens from 80 patients with atrial septal defect (n=10) ventricular septal defect (n=27), complete atrioventricular canal (n=27), miscellaneous lesions (n=8) and tetralogy of Fallot (n=8) were analyzed with a planimetric method. Additionally, wall thickness was determined in 52 patients by distance measurements. The ratio of alveoli/arteries per area of lung tissue was measured. Medial thickness was "increased" on distance measurements in 15% of the cases where planimetric data showed normal wall thickness. The ratio of alveoli/arteries varied up to 43% from the mean. Hemodynamic data obtained at a median (range) time of 2 months (1 day to 18 months) before the operation did not correlate with morphologic findings. In 27 patients hemodynamic data were recorded at a median time of 1 year (3 days to 44 months) after the operation. Intimal fibrosis occupying more than 10% of the vessel lumen was associated with persistent high pulmonary vascular resistance. We conclude that morphometric techniques are useful to determine the degree of fibrosis in advanced vascular lesions. Arterial density cannot be determined in biopsy specimens with adequate certainty.

Adolescent↗
PubMed1996

Anti-IgE in allergic sensitization.

Anti-IgE autoantibodies exist predominantly in the sera of patients with atopic disease. For some time such anti-IgE autoantibodies have been considered a phenomenon that may not be of clinical importance. The cloning of such anti-IgE autoantibodies has eliminated doubts of whether these antibodies exist, but it is still unclear whether such autoantibodies play a pathophysiological role. However, there are ongoing clinical trials that use humanized anti-IgE antibodies for passive immunization of atopic individuals. While this approach may not definitely clarify the role of anti-IgE autoantibodies, it will nevertheless clarify the role of IgE.

Animals↗
PubMed1996

Visually debilitating pterygium: surgical and contact lens treatment.

PURPOSE: We present the management of a patient with large pterygia complicated by irregular astigmatism and corneal opacities. Visual rehabilitation required both surgical excision and contact lens fitting. METHODS: We examined a 30-year-old man with hand motion vision from a large pterygium overgrowing his right cornea. Histopathology was consistent with pterygium. During the first few postoperative weeks, his uncorrected visual acuity improved to 20/60, and manifest refraction yielded no further improvement. In the subsequent months, there were increasing anterior stromal corneal opacities, and the refraction became hyperopic to a variable degree. RESULTS: Best corrected visual acuity was 20/70-20/100. Axial length was 22.64 +/- 0.07 mm. Computerized corneal topography 6 months postoperative was similar to the preoperative topography and revealed irregular and asymmetric astigmatism, with marked variation of the central corneal dioptric power. Slit lamp biomicroscopy suggested that the corneal opacities were responsible for the patient's decreased acuity; however, contact lens fitting provided 20/30 vision with a rigid gas permeable contact lens. CONCLUSIONS: The improved vision with contact lens therapy strongly suggested that the irregular and asymmetric astigmatism were more visually significant than the corneal opacities.

Adult↗
PubMed1996

Cross reactive anti-tetanus and anti-melittin Fab fragments by phage display after tetanus toxoid immunisation.

Amino acid sequence homology between tetanus toxoid, a common vaccine and melittin, a bee venom allergen provided us with two antigen models for studying the production of cross reactive antibodies after immunisation. Analysis of the serum of an atopic patient recently boosted with tetanus toxoid revealed the presence of anti-melittin and anti-tetanus antibodies. From this donor a phage display Fab library was constructed five days after vaccination. Screening of this library either with melittin alone or with tetanus toxoid followed by melittin allowed the isolation of Fab fragments specific to melittin but also Fab fragments which cross react with melittin and tetanus toxoid. Amino acid analysis revealed diversity in the heavy and the light Ig chains of the melittin specific and of the cross reactive clones. Interestingly we found that the light chain recognised melittin whereas the heavy chain preferentially bound to tetanus toxoid suggesting that cross reactivity may be due to the different binding specificities of the individual Ig chains.

Amino Acid Sequence↗
PubMed1995

Microcallus formations of the cancellous bone: a quantitative analysis of the human spine.

Microcallus formations are demonstrable in nearly all spongy bone by means of suitable preparation techniques. Histologically, these structures are immature fibrous bone. Their genesis, frequency, and importance are largely unknown. To address these issues, 26 normal human spines, 11 osteoporotic spines, and different parts of the skeleton (femur head, iliac crest) were investigated for microcallus using a new preparation technique--allowing a combined 2- and 3-dimensional analysis. According to our analysis, microcallus formation occurs frequently in persons older than 45 years of age. These formations are mainly localized in the lower thoracic and lumbar spine and are obviously more frequent in females than in males. In individuals with a trabecular bone volume (BV/TV) in the spine below 11%, microcallus formations occur regularly. But the number of microcallus formations depends more on the microarchitecture of the cancellous bone (trabecular bone pattern factor, TBPf), than on individual trabecular parameters (trabecular number, TbN; trabecular bone volume, BV/TV; and trabecular thickness, TbTh). In about 33% of cases microfractures are demonstrable in the center of the microcallus formation. It is unclear whether microcallus may be the result of a nontraumatic process. In therapy studies the bone mass could be misrepresented due to the amount of microcallus. Although it indicates instability of the bone structure, microcallus formation is not only a negative mechanism, but stabilizes and regenerates the bone tissue. Furthermore, complete new trabeculae can be formed due to bridges of microcallus between the remnant trabeculae. Osteoporosis is not the result of an inability to form microcallus formations.

Adolescent↗
PubMed1995

Influence of clinical and ventilatory parameters on morphology of bronchopulmonary dysplasia.

Our aim was to assess multiple factors which contribute to bronchopulmonary dysplasia (BPD) in prematurely born neonates. Specific morphologic features might relate to cumulative oxygen dose, barotrauma, prematurity, infection, and persistent ductus arteriosus (PDA). Seventy-two patients dying from BPD as defined by the histopathologic criteria of Stocker were analyzed retrospectively. Median (range) gestational age was 28 (25-35) weeks, and median survival was 16 (5-386) days. The infants were ventilated for 15 (15-149) days with a mean inspired oxygen fraction (FiO2) of 0.78. The cumulative oxygen dose and mean airway pressures were determined. The presence of neonatal infection, PDA, and interstitial lung emphysema (ILE) was assessed. Baseline lung disease was estimated as proposed by Palta. At autopsy, the degree of hyaline membranes, epithelial cell necrosis, emphysema, atelectasis, interstitial cell proliferation, and lung fibrosis was scored semiquantitatively (0 to 3+). The influence of neonatal infection, PDA, gestational age, survival, oxygen dose, or barotrauma on morphological findings was examined by multivariate analysis. We found "acute" BPD in 22, "reparative" in 34 and long-standing-"healed" in 16 cases. ILE within the first week was associated with interstitial cell proliferation and lung fibrosis in infants surviving more than 28 days. Initial barotrauma contributes to lung fibrosis in infants with BPD.

Autopsy↗
PubMed1995

Trabecular bone structure in patients with primary hyperparathyroidism.

To evaluate the effects of increased parathyroid hormone (PTH)-secretion on trabecular bone structure in patients with primary hyperparathyroidism (PHPT) we have analysed iliac crest biopsies from 84 patients (38 male, 46 female, age 20-85 years) with surgically proven PHPT by using quantitative histomorphometry. As there might be an influence of age or sex, subjects were divided into 4 subgroups according to age (younger than 50 years, older than 50 years) and sex. Eighty four age and sex matched autopsy cases of accidental death served as controls. When compared with age matched controls, trabecular bone volume (BV/TV) and trabecular diameter in PHPT were increased. Trabecular density in PHPT was elevated significantly in the older age-groups. These results suggest a preservation of intertrabecular connectivity, which we were able to confirm by measurement of the number of intertrabecular nodes and trabecular bone pattern factor (TBPf). No differences were demonstrated between male and female subjects. Furthermore, no variations according to the histological type (with or without endosteal fibrosis) could be demonstrated in our material. We conclude that increased trabecular bone volume in PHPT is the result not only of thicker trabecula but also of a reduction of the age-dependent loss of complete trabecular plates due to perforations. Thus PHPT leads to a substantial preservation of intertrabecular connectivity.

Adult↗
PubMed1995

Three-dimensional echocardiography can simulate intraoperative visualization of congenitally malformed hearts.

BACKGROUND: The new technique of three-dimensional echocardiography can display the studied anatomy in any desired view plane. We sought to establish whether the reconstructions produced could provide views of the heart comparable with those obtained by the surgeon in the operating room. METHODS: Ninety-four patients, aged 1 day to 19 years (mean, 4.3 years), were examined. The ultrasound probe was placed either on the chest or subcostally and acquired 80 to 100 perpendicular parallel images of the heart with electrocardiographic and respiratory gating. Any plane, in particular oblique planes, within the data set can be analyzed. Whenever possible, the arrangement as seen by the surgeon was photographed, or heart specimens with similar intracardiac lesions were cut to simulate the view of the surgeons, to validate the echo-cardiographic reconstructions. RESULTS: Three-dimensional reconstruction of perimembranous ventricular septal defects, atrial septal defects, or anomalies of the atrioventricular valves could be displayed as viewed through an atriotomy. In similar fashion, reconstructions of muscular or doubly committed ventricular septal defects, along with obstruction of the right ventricular outflow tract, could be prepared as seen through a right ventriculotomy. Obstruction of the left ventricular outflow tract was shown as viewed through an aortotomy. Transthoracic three-dimensional echocardiography provided additional information in the prospective diagnosis of supravalvar mitral membrane, doubly committed subarterial ventricular septal defect, and subaortic stenosis caused by a restrictive ventricular septal defect in double inlet left ventricle. CONCLUSIONS: Three-dimensional echocardiography can simulate the display of the heart as seen by the surgeon in the operating room, and therefore can aid in better planning of surgical repair.

Adolescent↗
PubMed1995

Acute and chronic fetal hypoxia in monochorionic and dichorionic twins.

OBJECTIVE: To assess the risk for acute and chronic fetal hypoxia in twin pregnancies. METHODS: We investigated 50 sets of twins (24-38 weeks' gestation, 660-3200 g birth weight) admitted consecutively to our neonatal intensive care unit. Seventy-six infants were appropriate for gestational age (AGA; tenth to 90th percentile), 20 were small for gestational age (SGA; below the tenth percentile), and four were large for gestational age (above the 90th percentile). Twenty-six singleton AGA term newborns served as controls. Umbilical arterial pH was used as a marker for acute and umbilical venous erythropoietin concentration for chronic fetal hypoxia. The results are given as median followed by quartiles. RESULTS: We identified 40 sets of diamniotic-dichorionic twins and ten sets of diamniotic-monochorionic twins with transplacental vascular shunts. In the second-born twin, umbilical arterial pH was lower (7.29, 7.23-7.33) than in the firstborn (7.31, 7.25-7.34) (P = .03), and the incidence of a low pH (less than 7.20) was higher (19 versus 11%). Two second-born twins and none of the firstborn twins had an umbilical arterial pH less than 7.05. In SGA twins, the erythropoietin concentration was elevated (34.8, 22.8-325 mU/mL) compared with that in AGA twins (16.2, 8.2-26.6 mU/mL) (P < .01). In AGA twins, erythropoietin concentration did not differ from that in AGA singleton newborns (19.6, 14.7-31.6 mU/mL). In 12 of 17 twin sets with weight discordancy greater than 15% and in all five twin sets with weight difference greater than 25%, erythropoietin concentration was higher in the smaller twin. The proportion of infants and of complete sets with elevated erythropoietin levels was higher (P < .01) in monochorionic than in dichorionic pregnancies. CONCLUSION: The second-born twin is at increased risk for acute birth asphyxia. Fetal growth restriction in twin pregnancies is associated with chronic fetal hypoxia. Monochorionic twins are at higher risk for chronic fetal hypoxia than are dichorionic twins.

Acute Disease↗
PubMed1995

Delineation of site, relative size and dynamic geometry of atrial septal defects by real-time three-dimensional echocardiography.

OBJECTIVES: This study attempted to determine the site, relative size and dynamic geometry of atrial septal defects using dynamic three-dimensional echocardiography. BACKGROUND: Recent studies have demonstrated the feasibility of dynamic three-dimensional echocardiography. Images are acquired from computerized reconstruction of sequential, tomographic ultrasound "slices" of the heart. Ultrasound images can be obtained by linear progression of a transducer within a transesophageal imaging probe. In small infants and children the large transducer size has not allowed transesophageal placement, and the probe has been placed on the thorax or in the subcostal position. Other scanning devices, housed in plastic containers, acquire images in a rotational format and can also be placed in a transthoracic or subcostal position. METHODS: Specially designed transesophageal probes and a dedicated computer unit were used for two-dimensional image retrieval and reconstruction of three-dimensional images. Sixteen patients with atrial septal defects were studied (median age 18 months, range 1 day to 18 years). In one patient, images were obtained by transesophageal probe placement; in the other 15 patients, the probe was placed in the transthoracic or subcostal position. RESULTS: A dynamic three-dimensional echocardiogram of the atrial septal defect could be obtained in 13 of the 16 patients. The distinguishing features of the atrial septal defects and their spatial orientation could be visualized in unique three-dimensional views. CONCLUSIONS: Dynamic three-dimensional imaging could be applied to the specific evaluation of atrial septal defects. Unique views of the heart allowed for spatial comprehension of the defects, rendering potentially important clinical information.

Echocardiography, Transesophageal↗
PubMed1995

Intervertebral variation in trabecular microarchitecture throughout the normal spine in relation to age.

The vertebral bodies of the complete spine (C-3-L-5) were removed in 26 autopsy cases without evidence for primary or secondary bone disease (13 males aged 19-79 years and 13 females aged 17-90 years). A sagittal segment through the center of all vertebral bodies was embedded undecalcified in hydroxyethylmethacrylate and processed to so-called surface stained block grindings. Histomorphometric analysis of the complete segment was performed using a computer-assisted image analysis system (IBAS 2000). The structural parameters investigated were bone volume (BV/TV) and trabecular interconnection quantificated by trabecular bone pattern factor (TBPf). A close correlation of BV/TV and TBPf was found in all vertebral bodies irrespective of vertebral region (r = 0.8, p < 0.001). This indicates that the age-related decrease of trabecular bone mass is primarily the consequence of the transformation from plates to rods and the loss of whole trabecular structures. This basic principle is valid throughout the complete spine. However, the systematic analysis of vertebral trabecular bone from C-3 to L-5 revealed a significant intervertebral variation of trabecular microarchitecture. The density of trabecular structure of cervical vertebrae is much higher than that of thoracic and lumbar vertebrae (p < 0.001). The extent of age-related loss of trabecular bone mass and structure showed a decrease within the spine from the caudal to the cranial region (p < 0.05). The loss of bone volume in individuals between the ages of 30 and 80 years in the lumbar spine was 53%, whereas in the thoracic spine the decrease was 41%, and in the cervical spine only 24%.(ABSTRACT TRUNCATED AT 250 WORDS)

Absorptiometry, Photon↗
PubMed1995

Polyclonal preparations of anti-tetanus toxoid antibodies derived from a combinatorial library confer protection.

We have compared the in vivo therapeutic potential of anti-tetanus toxin (TT) human Fab antibodies derived from a combinatorial phage display library to established polyclonal and monoclonal reagents. The oligoclonality and fine specificity distribution of the synthetic anti-TT Fab preparations was comparable to the antibody spectrum present in the donor serum and the affinities determined for the synthetic phage-bound Fab (Phab) and soluble Fab were in the same range as their monoclonal and polyclonal counterparts. On a weight basis, the protective capacity of the new oligoclonal preparations in vivo (16.4 IU/100 micrograms Fab) was comparable to those of the best combinations of hybridoma derived human monoclonal antibodies, and far better than those exhibited by the polyclonal serum antibodies of the donor (0.29 IU/100 micrograms IgG) or by a standard commercial human tetanus immunoglobulin preparation. These data suggest that recombinant antibodies may become a safe and effective alternative to human plasma-derived immunoglobulins for passive immunization.

Animals↗
PubMed1995

Assessment of congenital heart defects by dynamic three-dimensional echocardiography: methods of data acquisition and clinical potential.

To evaluate the use of three-dimensional (3D) echocardiography in the diagnosis of congenital heart defects, we studied 238 patients aged 3 days to 19 years (mean 4.3 years) with normal hearts (n=13) or a variety of congenital heart defects (n=225). Three different modalities of data acquisition suitable for 3D reconstruction were applied. For parallel scanning, the transducer is held in a 6-cm long scan frame and then moved over the thorax, or in the subcostal position, by a stepper motor using 0.5-mm steps with acquisition of perpendicular parallel images of the heart. For rotational scanning, the transducer is rotated at sectors of 2 degrees over a span of 180 degrees. For fan-like scanning, the transducer is moved in an arc 45 degrees each way from its vertical axis. Movement of the transducer is computer-controlled and performed with electrocardiographic and respiratory gating. Between 80 and 120 slices of the heart are thus obtained, which form the 3D dataset. This dataset can then be ¿sectioned¿ in any desired plane, thus permitting generation of views simulating intraoperative perspectives. Ventricular septal defects and atrioventricular valves can be displayed as viewed via the atrium. Muscular ventricular septal defects can be viewed as seen through a ventriculotomy. Obstruction in the left ventricular outflow tract can be viewed as via an aortotomy, and so on. We concluded that this new imaging modality has a vast potential and may facilitate planning of intracardiac surgery.

Adolescent↗
PubMed1995

Amoxicillin pharmacokinetics in preterm infants with gestational ages of less than 32 weeks.

The multiple-dose pharmacokinetics of amoxicillin (AM [administered twice daily in a 25-mg/kg of body weight intravenous dose]) in 17 preterm infants (11 males; gestational age, 29 +/- 1.9 weeks; birth weight, 1,175 +/- 278 g) were evaluated on day 3 of life. Blood samples were collected from an arterial catheter at 0, 0.5, 1, 2, 4, 8, and 12 h after the intravenous dose. A high-performance liquid chromatography method was used to determine AM concentrations in serum. AM pharmacokinetics followed a one-compartment open model. The glomerular filtration rates of all patients were simultaneously studied by means of the 24-h continuous inulin infusion technique. The elimination half-life, apparent volume of distribution, and total body clearance of AM (mean +/- standard deviation) were 6.7 +/- 1.7 h, 584 +/- 173 ml, and 62.4 +/- 23.3 ml/h, respectively. The mean (+/- standard deviation) AM peak and trough levels were 53.6 +/- 9.1 and 16.0 +/- 4.9 mg/liter, respectively. All infants had a serum trough level above 5 mg/liter. The total body clearance and apparent volume of distribution of AM and the clearance of inulin increased significantly with increasing gestational age. The total body clearance of AM (1.0 +/- 0.4 ml/min) and the clearance of inulin (1.0 +/- 0.3 ml/min) were similar. The total body clearance of AM increased significantly with increasing clearance of inulin. We conclude that an AM dose of 25 mg/kg every 12 h given to preterm infants in the first week of life with gestational ages of less than 32 weeks results in serum levels well above the MIC for major microorganisms involved in neonatal infections.

Amoxicillin↗
PubMed1995

Comparison of three dimensional echocardiographic findings with anatomical specimens of various congenitally malformed hearts.

OBJECTIVE: To compare the reconstructions obtained by three dimensional echocardiography with the anatomical specimens used to generate the echocardiograms. DESIGN: The heart specimens were immersed in a water bath and imaged with a 5 MHz echocardiographic transducer mounted into a scan frame which allowed the transducer to travel a total distance of 4.4 cm in steps of 0.25 mm. The transducer records a tomographic slice at each incremental level thus producing 176 parallel slices of the heart to form the dataset. Reconstruction of the anatomical structures of the heart in a three dimensional format is achieved by means of different grey scales. MATERIALS: 72 specimens of either normal or various congenitally malformed hearts. RESULTS: Good quality echocardiographic pictures were obtained, permitting three dimensional reconstructions in each heart. The cardiac chambers and valves could be displayed in a three dimensional format which accurately displayed the internal anatomy of the specimens. No artefacts, such as spurious septal defects, were produced in specimens with intact septums. The atrioventricular valvar leaflets, however, appeared thicker in the images than they were in the specimens. CONCLUSIONS: Three dimensional echocardiography accurately displays the anatomy of normal and congenitally malformed hearts.

Echocardiography↗
PubMed1995

In vitro validation of right ventricular volume measurement by three dimensional echocardiography.

OBJECTIVE: Evaluation of ability of three dimensional echocardiography to accurately assess right ventricular volumes in vitro. METHODS: Silicone casts of normal human right ventricles were examined. Each was filled with three different volumes of water to yield 15 different measurements. The casts were examined in a waterbath with three dimensional echocardiography using a 7.5 MHz ultrasound probe mounted in a scan frame. It was steered by a stepper motor, which moved the probe in steps of 0.25 mm over a distance of 5.9 cm inside the frame, acquiring an image at each step. 236 parallel slices of the cast were thus obtained, forming the three dimensional dataset. The longest axis of the right ventricular volume was defined and the area of perpendicular 1 mm thick slices was outlined manually to calculate the area of each slice. This was multiplied by the slice thickness to obtain the volume of each slice; the respective volumes were added to obtain the volume of the whole cast. RESULTS: The casts had a median volume of 31.1 (23) ml (range 15-100); three dimensional echocardiography gave a median volume of 29.0 (21.7) ml (15.7-91.7). Interobserver variability was 4.5% (0.4%-13.6%) and intraobserver variability 4.3% (0.2%-9.3%). Correlation between real cast volumes and volumes measured by three dimensional echocardiography was 0.99 (y = 1.08 x -0.16) with an SEE of 2.7 ml. Limits for agreement between methods ranged from -3.1 ml to 8.3 ml. In 14 of the 15 measurements, volume by three dimensional echocardiography was smaller than real volume, with the mean difference being 7.4% (2.8%-19.5%). This may be due to the thickening of surfaces of structures when imaged by ultrasonography. CONCLUSION: Right ventricular volumes can accurately be determined by three dimensional echocardiography.

Echocardiography↗