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Biomedical subjects

R Buhl

Publications and source records attributed to R Buhl.

At least 91 records · Page 5Linked to original sources
PubMed1999

Mediastinal lymph nodes demonstrated by mediastinal sonography: activity marker in patients with cystic fibrosis.

PURPOSE: To evaluate the potential diagnostic role of mediastinal sonography in patients with cystic fibrosis (CF), we screened the mediastinum of adult CF patients with and without signs of infection and healthy controls. METHODS: Fifty-four consecutive adult patients with CF and 53 healthy volunteers underwent high-resolution mediastinal sonography. The paratracheal region and aorticopulmonary window of each subject were examined for lymph nodes. Each patient was screened for clinical signs of infection. RESULTS: Lymph nodes were detectable in the mediastinum of 39 of 50 CF patients (78%); the mean total lymph node volume was 1.5 +/- 1.7 cm3. Lymph nodes were detectable in the mediastinum of 31 of 50 controls (62%); the mean total lymph node volume in this group was 0.3 +/- 0.3 cm3 (p < 0.001). In the 30 CF patients with signs of infection, the mean total lymph node volume was larger (2.0 +/- 1.8 cm3) than in the 20 CF patients without signs of infection (0.7 +/- 0.9 cm3; p = 0.002). CONCLUSIONS: These results indicate that lymph node volume determination by high-resolution mediastinal sonography may help assess inflammatory activity in patients with CF.

Adolescent↗
PubMed1999

Indoor air pollutants stimulate interleukin-8-specific mRNA expression and protein secretion of alveolar macrophages.

Indoor air pollutants may cause inflammatory changes of the airways and adjacent pulmonary tissue. After phagocytosis of inhaled particles alveolar macrophages (AM) release chemotactic mediators capable of attracting inflammatory cells into the lung tissue. To evaluate these mechanisms further peripheral blood mononuclear cells (PBMNC) and human AM (freshly recovered from the lower respiratory tract) were exposed to the indoor particles Soot FR 101 and Printex 90, the asbestos fiber Chrysotile B, and titanium dioxide (TiO2) at concentrations of 10 or 50 microg/10(6) cells for up to 8 h. The migration of granulocytes into the conditioned supernatants of AM and PBMNC was quantified by chemotaxis assay in a Boyden chamber. Granulocyte migration increased by 42.3 +/- 25.8% (Chrysotile B), 64. 6 +/- 18.3% (FR 101), 74.2 +/- 16.5% (P 90), and 86.7 +/- 25.6% (TiO2) in AM-conditioned supernatants (p < 0.05). Qualitative, Interleukin (IL)-8 specific reverse transcriptase-polymerase chain reaction was performed after exposure of AM or PBMNC to Chrysotile B, FR 101, P 90, and TiO2 at concentrations of 10 and 50 microg/10(6) cells for 90 min. Each of the tested particles caused an increase in IL-8-specific mRNA expression of AM or PBMNC after particle exposure compared with the unexposed control. To find out if IL-8, the most powerful granulocyte chemokine, is involved, supernatants were preincubated with anti-IL-8. Granulocyte migration decreased by up to 35 +/- 15% (50 ng/ml anti-IL-8) and 41.5 +/- 16% (100 ng/ml anti-IL-8) (p < 0.0625) in AM-conditioned supernatants. Pretreatment of the granulocytes with human IL-8 decreased by up to 59 +/- 18% (10 ng/ml) (p < 0.0625) in AM-conditioned supernatants. Similar reaction patterns were observed using anti-IL-8-pretreated supernatants of particle-exposed PBMNC. In conclusion, indoor air pollutants may promote inflammatory changes in the lung via IL-8 release by alveolar macrophages.

Adult↗
PubMed1999

Effect of internal thoracic artery preparation on blood loss, lung function, and pain.

BACKGROUND: Postoperative blood loss, respiratory distress, and pain after coronary artery operation were assessed in a prospective, randomized, clinical study comparing two techniques of internal thoracic artery preparation. METHODS: In group A (n = 57) the internal thoracic artery was dissected with the entire surrounding connective tissue after opening the pleura, using routine lateral pleural drainage. In group B (n = 55) a venoarterial pedicle was prepared without surrounding muscle leaving the pleura intact. We assessed blood loss, clinical outcome, lung function, location, intensity, and quality of pain 6 days and 3 months after the operation. RESULTS: Significantly higher blood loss was observed in group A (A, 608+/-58 mL; B, 470+/-48 mL; p = 0.027). Forced expiratory volume in 1 second was significantly decreased in group A 6 days after surgery (A, 76.0%+/-1.6%; B, 83.2%+/-1.6%; p = 0.020). The forced expiratory volume in 1 second correlated to inspiratory vital capacity, which confirmed the advantage of the venoarterial technique (A, 0.771+/-0.021; B, 0.832+/-0.020; p = 0.003). Vital capacity was significantly higher in the venoarterial group at 3 months (A, 85.2%+/-2.1%; B, 98.5%+/-1.2%; p = 0.009), but not on postoperative day 6. The incidence of pleural effusion and atelectasis was significantly higher in group A (effusion: A, 52.6%; B, 23.6%; p = 0.002; atelectasis: A, 42.1%; B, 20.0%, p = 0.015). Sternal pain (A, 36.8%; B, 9.1%; p = 0.001) and suspenders pain (A, 33.3%; B, 7.3%; p = 0.001) occurred more often in group A. When using a multidimensional pain score, patients in group A experienced significantly sharper (6 days: A, 6.7+/-0.3; B, 3.3+/-0.2; p = 0.018; 3 months: A, 3.5+/-0.3; B, 1.4+/-0.3; p = 0.046) and more annoying pain (6 days: A, 7.6+/-0.2; B, 2.7+/-0.1; p = 0.036; 3 months: A, 6.6+/-0.3; B, 2.3+/-0.2; p = 0.040). CONCLUSIONS: These results demonstrate that the venoarterial preparation technique is superior to conventional internal thoracic artery preparation regarding postoperative blood loss, lung function, and pain.

Female↗
PubMed1999

Giant ventral intradural extramedullary neuroma: case report

OBJECTIVE AND IMPORTANCE: We report an extremely rare, giant, ventrally located, intradural extramedullary neuroma in a 32-year-old woman. It extended from the foramen magnum to the level of the 10th thoracic vertebra. To our knowledge, this is the largest reported intraspinal neuroma. CLINICAL PRESENTATION: A mixed polyradicular and medullary lesion with symptoms and signs of raised intracranial pressure was observed on clinical presentation. Magnetic resonance imaging of the entire neuraxis was suggestive of a neuroma. Histological findings revealed characteristics of a classic neuroma. INTERVENTION: A complete surgical excision of the tumor was accomplished through an osteoplastic laminotomy from C1 to T10 with monitoring of the somatosensory evoked potentials. CONCLUSION: Even such a huge, ventrally located, intradural extramedullary tumor, as in this patient, can be completely removed with good results when a preoperative radiological and histological diagnosis is considered. With the help of new-generation magnetic resonance imaging scans, the intradural neural, vascular, and other structures can be clearly outlined. These tests also obviate the need for invasive diagnostic procedures such as myelography. We recommend an osteoplastic laminotomy instead of laminectomy to reduce the risk of postoperative spinal instability.

Journal Article↗
PubMed1999

Glutathione aerosol suppresses lung epithelial surface inflammatory cell-derived oxidants in cystic fibrosis.

Cystic fibrosis (CF) is characterized by accumulation of activated neutrophils and macrophages on the respiratory epithelial surface (RES); these cells release toxic oxidants, which contribute to the marked epithelial derangements seen in CF. These deleterious consequences are magnified, since reduced glutathione (GSH), an antioxidant present in high concentrations in normal respiratory epithelial lining fluid (ELF), is deficient in CF ELF. To evaluate the feasibility of increasing ELF GSH levels and enhancing RES antioxidant protection, GSH aerosol was delivered (600 mg twice daily for 3 days) to seven patients with CF. ELF total, reduced, and oxidized GSH increased (P < 0.05, all compared with before GSH therapy), suggesting adequate RES delivery and utilization of GSH. Phorbol 12-myristate 13-acetate-stimulated superoxide anion (O2-.) release by ELF inflammatory cells decreased after GSH therapy (P < 0.002). This paralleled observations that GSH added in vitro to CF ELF inflammatory cells suppressed O2-. release (P < 0.001). No adverse effects were noted during treatment. Together, these observations demonstrate the feasibility of using GSH aerosol to restore RES oxidant-antioxidant balance in CF and support the rationale for further clinical evaluation.

Adult↗
PubMed1999

Effects of short-term inhaled fluticasone on oxidative burst of sputum cells in cystic fibrosis patients.

Inhaled corticosteroids have been proposed to decrease pulmonary inflammation in cystic fibrosis (CF). In this study the effects of therapy with inhaled fluticasone on clinical and sputum outcomes (leukocyte count, activity of myeloperoxidase, superoxide anion release) in adult CF patients were investigated in an open label design. Twenty-six stable patients (median+/-SD forced expiratory volume in one second (FEV1) 58.1+/-19.9% pred.) were randomly assigned to the study group (500 microg b.i.d., for three weeks) or the control group (n=14; nonsteroid medication). Sputum samples were obtained during inhalation of hypertonic saline (3%, 20 min), which was found not to alter the investigated sputum parameters. No significant changes in clinical parameters, sputum leukocyte count, activity of myeloperoxidase, and baseline superoxide anion release where observed following therapy. Surprisingly, stimulated superoxide anion release increased significantly after therapy (34.1+/-17.7 versus 25.2+/-17.4 nmol x hr(-1) x 10(6) cells, p<0.03) and exceeded spontaneous variability of this parameter (p=0.02 versus control group). In conclusion, in adult cystic fibrosis patients short-term fluticasone therapy had no evident effect on clinical and sputum parameters. Further investigations are necessary to evaluate whether the observed up-regulation of oxidative capacity of inflammatory cells is of concern or benefit in these patients.

Administration, Inhalation↗
PubMed1998

Modulation of cystic fibrosis transmembrane conductance regulator gene - expression by elevation of intracellular cyclic AMP.

Cystic fibrosis (CF) is caused by mutations of the cystic fibrosis transmembrane conductance regulator (CFTR) gene. Its product is a cyclic AMP-dependent Cl- channel, that is defective in CF. Since cAMP regulates the expression of many genes and since the 5'-flanking region of the CFTR gene contains cAMP response elements, we hypothesized that intracellular cAMP might modulate not only the cAMP-dependent Cl- channel CFTR, but also CFTR gene expression in epithelial cells. To accomplish this, we investigated Cl- secretion and CFTR-mRNA levels in HT-29 and T84 colon carcinoma epithelial cells before and after exposure to forskolin and 8-bromo-cAMP for 12 hr. While resting T84 cells increased Cl- secretion in response to forskolin strongly and immediately, HT-29 cells did not, although both cell lines showed highly increased Cl- efflux in response to A23187, a calcium ionophore. Interestingly, prolonged exposure to forskolin (12 hr) induced a clear decrease of CFTR-mRNA levels in T84 cells, but an increase of CFTR-mRNA levels in HT-29 cells, thus demonstrating different behaviour of CFTR gene regulation in different epithelial cells in response to intracellular cAMP. These results suggest that cells with an effective cAMP-dependent Cl- channel (CFTR) respond to prolonged stimulation of this channel with down-regulation of CFTR gene expression, while cells with no effective cAMP-dependent Cl--secretion respond with an up-regulation of CFTR gene expression.

8-Bromo Cyclic Adenosine Monophosphate↗
PubMed1998

Dural invasion of meningiomas adjacent to the tumor margin on Gd-DTPA-enhanced MR images: histopathologic correlation.

In intracranial meningiomas a flat, contrast-enhancing, dural structure adjacent to the tumor can occasionally be observed on gadolinium-DTPA-enhanced MR images. We wished to evaluate whether there is a correlation between MR images and meningeal invasion of intracranial meningiomas. The study included 54 patients with intracranial meningioma and the meningeal sign. MR studies included T2-weighted and gadolinium-DTPA-enhanced T1-weighted images in axial, coronal, and sagittal planes. Histopathologic examinations were done on the meningiomas adjacent to the dura mater. The meningeal sign on MRI was observed from 2 up to 35 mm from the main tumor mass in 31 (57 %) of the 54 patients. In 20 of these 31 the histopathologic examination showed tumor invasion, while 11 patients had no tumor invasion but tissue proliferation, hypervascularity, and vascular dilatation. Seven of the 23 meningiomas without the meningeal sign had histologically proven infiltration of the adjacent dura. MR imaging is not able to determine definitive whether or not there is dural infiltration of the meningiomas. In conclusion, resection of the tumor with a wide margin is necessary to achieve complete excision of meningioma and to avoid recurrence.

Contrast Media↗
PubMed1998

Spinal drop metastases in recurrent glioblastoma multiforme.

Multifocal dissemination of glioblastomas is very rare but is increasing as patients live longer. Between April 1994 and December 1997 one hundred and fifty one patients with a histologically proven glioblastoma multiforme were operated on in the Neurosurgical Department of the University of Kiel, Germany. Recurrent tumours of these patients were removed in 36 patients. Two patients developed multifocal spread of glioblastoma multiforme including spinal drop metastases. Both patients died 10 and 7 months after the primary operation. On histological examination both tumours showed wide perivascular tumour-cell cuffings in the surrounding brain tissue, so that this perivascular growth might be another explanation for the dissemination in these glioblastomas.

Brain↗
PubMed1998

Pseudotumour cerebri and optic hydrops--magnetic resonance imaging diagnostic and therapeutical considerations in a paediatric case.

We report the case of a 4-year-old girl with progressive visual loss. Magnetic resonance imaging (MRI) demonstrated a perioptic subarachnoidal space dilatation. In this case, a clear differentiation between pseudotumour cerebri and optic hydrops was not possible. Administration of acetazolamid, furosemid and corticosteroids did not show any success. Progressive loss of visual function was halted with ventriculo-peritoneal shunting. We discuss MRI findings, aetiology and course of the disease, and its literature.

Child, Preschool↗
PubMed1998

Glutathione in spermatozoa and seminal plasma of infertile men.

Glutathione has a central role in the defence against oxidative damage; however, the data on glutathione concentrations in the semen of infertile men are limited. To expand this knowledge the glutathione content of the ejaculates and blood plasmas of 77 infertile men and 11 controls were analysed. The concentrations of total glutathione were assessed in spermatozoa, seminal plasma and blood plasma using a coupled spectrophotometric assay. In the spermatozoa of patients with oligozoospermia the glutathione concentrations (2.57+/-0.96 nmol/10[8] spermatozoa; mean +/- SD) were significantly lower than in the controls (3.49+/-0.87 nmol/10[8] spermatozoa; P +/- 0.03). The glutathione content of spermatozoa from patients with normozoospermia showed large variations (3.04+/-1.37 nmol/10[8] spermatozoa). An association between the intracellular glutathione content and the ability to penetrate bovine cervical mucus was observed (r = 0.2, P = 0.04). The intracellular glutathione concentrations correlated with the glutathione levels in seminal plasma (r = 0.46, P < 0.0001). There was no correlation between glutathione concentrations in blood plasma and those in seminal plasma or in spermatozoa. The glutathione concentrations in seminal plasmas did not differ between the different groups, however, correlated with the serum follicle stimulating hormone concentrations (r = 0.53, P = 0.005). This study demonstrated that intracellular glutathione levels of spermatozoa are decreased in certain populations of infertile men.

Animals↗
PubMed1998

Long-term treatment of alpha1-antitrypsin deficiency-related pulmonary emphysema with human alpha1-antitrypsin. Wissenschaftliche Arbeitsgemeinschaft zur Therapie von Lungenerkrankungen (WATL)-alpha1-AT-study group.

Alpha1-antitrypsin (alpha1-AT) deficiency is a genetic disorder characterized by low serum levels of alpha1-AT and a high risk of pulmonary emphysema at a young age. The resulting surplus of proteases, mainly of neutrophil elastase, can be balanced by i.v. augmentation with alpha1-AT. However, it is not clear if affected patients benefit from long-term augmentation therapy and no long-term safety data are available. We examined 443 patients with severe alpha1-AT deficiency and pulmonary emphysema receiving weekly i.v. infusions of 60 mg x kg body weight(-1) alpha1-AT in addition to their regular medication. The progression of the disease was assessed by repeated lung function measurements, particularly the decline in forced expiratory volume in one second (deltaFEV1). Four hundred and forty three patients with alpha1-AT deficiency tolerated augmentation therapy well with few adverse reactions. The deltaFEV1 in 287 patients with available follow-up data was 57.1+/-31.1 mL x yr(-1). Stratified for baseline FEV1, the decline was 35.6+/-21.3 mL in the 108 patients with an initial FEV1 <30% and 64.0+/-26.4 mL in the 164 with FEV1 30-65% of predicted normal (p=0.0008). The remaining 15 patients had an initial FEV1 >65% pred. Long-term treatment with i.v. alpha1-antitrypsin in patients with severe alpha1-antitrypsin deficiency is feasible and safe. The decline in forced expiratory volume in one second is related to the initial forced expiratory volume in one second as in alpha1-antitrypsin deficient patients not receiving augmentation therapy.

Adult↗
PubMed1998

Intracranial cavernomas: indications for and results of surgery.

Between April 1991 and April 1997, 46 patients were treated in our department presenting with intracranial cavernomas. Initial symptoms were focal seizures, bleeding episodes, and/or headaches. Mean age was 41 year (range 9 to 68 years). There were 24 female and 22 male patients. Computed tomography and magnetic resonance imaging were performed in order to establish the diagnosis, angiography was only indicated when the hemorrhaged area was so close to the subarachnoid space in the vicinity of the basal cisterns that an aneurysm had to be ruled out. Aggressive indication for surgery also in brainstem cavernomas was based on the natural history of the lesion, since the majority of patients presenting with intracranial bleeding had suffered several (up to six) episodes of previous hemorrhages. Patients' clinical status upon admission and accessibility of the cavernoma were taken into account for planning the operation. The operative planning and approach were greatly facilitated by using a neuronavigational device and intraoperative electrophysiological monitoring particularly in cavernomas located in the brainstem, thalamus, and medulla oblongata. Surgical removal of the lesions resulted in a new permanent neurological deficit only in two patients (4%). These data show that patients benefit from modern neurosurgical techniques in contrast to conservative approach in this disease of rather prolonged natural course.

Adolescent↗
PubMed1998

[Effectiveness and tolerance of a combination of fluticasone and salmeterol in patients with obstructive airway diseases. DUO Study Group].

The purpose of this open multicentre study was to evaluate prospectively the efficacy and safety of a combination of fluticasone (250 micrograms b.i.d.) and salmeterol (50 micrograms b.i.d.), both given by a metered dose inhaler, in 413 patients (mean age [+/- SEM] 46.9 +/- 0.7 years) suffering from obstructive airways disease (FEV1 % predicted 73 +/- 1.1%) for 10 +/- 0.5 years. 8 weeks of therapy with both drugs improved FEV1 and peak expiratory flow by 24 +/- 3.1% and 27 +/- 2.7%, respectively. Daytime and nocturnal symptoms, rescue beta 2 agonist use, days off work, and symptoms during working hours decreased. Similarly, the quality of sleep improved (p < 0.001, all comparisons to baseline). More than 80% of patients and physicians independently classified the study medication as superior to their previous therapy. Adverse events possibly, likely or definitely related to the study medication were seen in 9% of patients. In conclusion, an inhaled corticosteroid (fluticasone) together with an inhaled long-acting beta 2 agonist (salmeterol) is an effective and well tolerated therapy in patients with obstructive airways disease.

Administration, Inhalation↗
PubMed1998

[Spontaneous spinal epidural hematoma: good outcome after delayed treatment].

Spinal epidural haematomas are rare and are often encountered after previous operations on spinal disease and in combination with anticoagulation therapy. Usually early diagnosis and surgical treatment are the most important factors for a good result and neurological recovery. In 4 cases of spinal epidural haematoma treated in our institution, we found that also after some delay of diagnosis and treatment, surgery is always worthwhile even after some days to achieve a better neurological function.

Aged↗