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G Pfeiffer

Publications and source records attributed to G Pfeiffer.

At least 19 recordsLinked to original sources
PubMed2006

[Analgesia of the axilla using a paravertebral catheter in the lamina technique].

A 62-year-old female suffered from therapy-resistant pain in the axilla after lymphadenectomy. The pain ranged from 8-10 on the numeric rating scale (NRS) despite multimodal pain therapy (non-steroid anti-rheumatics, opioids, physiotherapy, acupuncture). A paravertebral trial injection was performed preoperatively on the laminae of the thoracic vertebrae Th 2-Th 4. As the patient responded well, a paravertebral catheter was inserted close to Th 4 directly before the revision operation took place the following day. The case study describes the possibilities of eliminating pain segmentally in the axilla and an alternative technique to a paravertebral block (lamina technique).

Acupuncture↗
PubMed2004

[Inadvertent intravenous infusion of 380 mg ropivacaine].

This is a report about an inadvertent intravenous infusion of 380 mg ropivacaine in a 84-year-old patient over a period of 1.75 h. The level of serum ropivacaine measured immediately after the end of the infusion as well as 2 h and 7 h later, was initially in the lower toxic range (free concentration of 0.48 micro g/ml). The patient showed no symptoms of intoxication neither clinically nor during the technical examinations (EEG, ECG). This case confirms the wide therapeutic range of ropivacaine.

Aged↗
PubMed2003

IGFs, basic FGF, and glucose modulate proliferation and apoptosis induced by IFNgamma but not by IL-1beta in rat INS-1E beta-cells.

We investigated the effects of glucose and beta-cell growth factors (IGF-I, IGF-II, bFGF) on growth and apoptosis in the presence and absence of apoptosis inducing cytokines (IFNgamma, Il-1beta, TNFalpha). Rat INS-1E beta-cell viability was measured by WST-1 viability assay and cell counting, apoptosis by FACS analysis of annexin-V-FITC and fluorescein-dUTP (TUNEL-staining)-positive cells. Glucose alone maintained INS-1E beta-cell viability at high physiological concentrations (6.2-12.5 mmol/l), addition of IGF-II alone or in combination with bFGF further increased these glucose effects. The cytokines IFNg and IL-1beta, but not TNFalpha strongly induced INS-1E beta-cell apoptosis. Interestingly, glucose alone induced apoptosis at extremely low or very high concentrations. In combination with IFNg, low glucose (1.6 mmol/l) increased apoptosis by 25.6% (1SD 5.0%) and high glucose (50 mmol/l) by 22.8% (1SD 2.8%) compared to 12.5 mmol/l glucose. In contrast, glucose failed to modulate IL-1beta-induced apoptosis. Most importantly, IGF-II and bFGF inhibited apoptosis induced by IFNg, but not by IL-1beta. Therefore, IGF signaling, supported by bFGF and optimal glucose levels, maintains beta-cell viability in vitro. Cytokines IFNg and IL-1beta differentially interfere with intracellular signaling cascades stimulated by IGFs and bFGF or glucose, respectively.

Animals↗
PubMed2001

The role of mutant Apc in the development of dysplasia and cancer in the mouse model of dextran sulfate sodium-induced colitis.

BACKGROUND & AIMS: Differences in genetic background may play a role in the development of ulcerative colitis (UC)-related neoplasia. Loss of heterozygosity (LOH) of APC has been reported in human UC-associated neoplasia. To investigate the role of genetic differences in UC-associated neoplasia, we compared differences in dextran sodium sulfate (DSS) colitis-associated neoplasia between wild-type C57BL/6J mice (WT-DSS) and C57BL/6J mice with a germline mutation in Apc (Min-DSS). METHODS: DSS colitis was induced in female wild-type and Min mice. Age- and sex-matched non-DSS-treated Mins were also studied. Animals were sacrificed after 1 and 2 cycles of DSS. The cecums and large intestines were studied for numbers of dysplasias/cancers. Dysplasias were studied for LOH of Apc. RESULTS: No WT-DSS, 100% of Min-DSS, and 50% of non-DSS-treated Mins had dysplasia. The mean numbers of lesions per mouse were 0 (WT-DSS), 15.6 and 29.3 (1 and 2 cycles Min-DSS, respectively), 1.2 and 1.9 (age-matched control Min, 1 and 2 cycle equivalents, respectively; P < 0.0002, Min-DSS vs. WT-DSS and non-DSS-treated Min; P = 0.03, Min-DSS 2 cycle vs. Min-DSS 1 cycle). Cancers were seen in 0%, 22%, and 40% of non-DSS Min, Min-DSS-1 cycle, and Min-DSS-2 cycle animals, respectively. LOH of Apc was observed in 90.6% of dysplasias and 6% of nondysplastic mucosa. CONCLUSIONS: A germline mutation in Apc contributes significantly to the development of colitis-associated neoplasia. Colitis markedly accelerates the development of dysplasia and cancer in the Min mouse. Dysplasia in Min-DSS occurs through LOH of Apc.

Adenoma↗
PubMed2001

Disability and quality of life in Charcot-Marie-Tooth disease type 1.

OBJECTIVES: Charcot-Marie-Tooth disease type I (CMT1) is a hereditary sensorimotor neuropathy causing variable degrees of handicap. The risk for relevant disability in respect to genetic counselling is unknown. An attempt was made to define it. METHODS: Disability and ambulation of 50 patients with CMT1 were scored by the Hauser ambulation index score and the Rankin scale. Rankin score 2 was subdivided into 2a (independent without relevant slowness) and 2b (independent, though at the cost of excessive time consumption). The sickness impact profile was assessed and compared with patients 6 months after stroke who were without mental deficit. To define at which degree sickness and disability become relevant for genetic counselling, the patients were asked whether they would refrain from childbearing if the children were at risk of inheriting a disease that caused as much disability as they experienced themselves. RESULTS: Subdivision of Rankin score 2 was reliable and improved validity. High disability significantly predicted an attitude against childbearing (stepwise logistic regression) only with this subdivision. Thirty six per cent of the patients voted against childbearing. The cut off for relevant disability in respect to childbearing was a Rankin score higher than 2a, which was present in 44% of the patients. Psychosocial impact was comparable with patients with stroke and similar disability. Depression was present in 18% of the patients. CONCLUSION: Subdivision of Rankin score 2 is recommended for the assessment of longstanding disability in neuromuscular disorders. Disability becomes relevant for the attitude towards childbearing as soon as everyday activities become markedly slow (Rankin score 2b). Relevant disability occurred in 44% of the patients. Emotional stress in CMT is similar to that of patients with stroke and comparable disability.

Adolescent↗
PubMed2000

Sensitivity and specificity of different conduction block criteria.

OBJECTIVES: To resolve the discrepancy between conduction block criteria derived from healthy controls and stricter criteria suggested by computer simulation of interphase cancellation through altered motor units. METHODS: An EMG database provided control nerves from patients with amyotrophic lateral sclerosis (ALS) or neural muscular atrophy (CMT1) (disease controls) and from subjects without neuromuscular diseases (healthy controls). We estimated normal limits from the healthy controls (criterion A) and from the pooled sample of healthy and disease controls (criterion B). We compared their sensitivity with that of an arbitrary limit of 0.5 (criterion C) in acute (AIDP) and chronic inflammatory demyelinating neuropathy (CIDP) and in multifocal motor neuropathy (MMNP). Specificity was assessed in ALS and CMT1. RESULTS: Limits estimated from healthy controls (criterion A: amplitude ratio of <0.7 in median and peroneal nerves and <0.8 in the ulnar nerve) gave false positive results in 17.3% of the ALS nerves. High scatter of the amplitude ratio of the nerves with distal response amplitudes below 1 mV required amplitude-dependent limits (0.36 for distal responses below 1 mV, 0.56 between 1 and 2 mV, and between 0.67 and 0.73 for higher response amplitudes) for criterion B. It was false positive in 4.3% of the ALS nerves and in 28.3% of the CMT1 nerves. A limit of 0.5 for nerves with distal responses above 1 mV and a limit of 0.36 for smaller responses (criterion D) avoided false positive results in ALS without further impairing sensitivity per patient in MMNP. Sensitivity in AIDP was 34.9% for criterion A, 19.5% for criterion B, and 10.2% for criterion D. Amplitude ratios were more sensitive than area ratios in CIDP and MMNP, but less specific in CMT1. CONCLUSIONS: Limits derived from healthy controls are unspecific in chronic neuromuscular diseases and in nerves with low response amplitudes. Criterion D should be used if motor unit restructuring or conduction delays have to be taken into account. Criterion A may be applicable in early AIDP if the distal response amplitude is above 1 mV.

Amyotrophic Lateral Sclerosis↗
PubMed1999

Isolated angiitis of the central nervous system: lack of inflammation after long-term treatment.

A case of isolated angiitis of the CNS was observed for 5 years. Initial response to cyclophosphamide was followed by relapse on therapy interruption. After renewed treatment, clinical stabilization was achieved despite progressive stenoses shown by angiography. The patient died of cyclophosphamide-induced myelodysplastic syndrome. Autopsy revealed lack of inflammation, vascular scarring, and amyloid angiopathy. We conclude that cure from isolated angiitis of the CNS is possible and that the risk of overtreatment should be minimized.

Adult↗
PubMed1999

The diagnostic power of motor unit potential analysis: an objective bayesian approach.

The notion of a "myopathic" or "neuropathic" electromyogram (EMG) is usually based on qualitative visual and acoustical impressions. Conventional quantification defines abnormality but not diagnosis, which requires interpretation of patterns of change. Discriminant analysis is a model for this multivariate decision. It tells how probable it is that a motor unit potential (MUP) comes from a normal, myopathic, or neuropathic muscle. Accumulation of single MUP information by a sequential Bayesian algorithm produced diagnostic probabilities above 0.95 in 91% of all muscles (223 biceps brachii muscles from 80 patients with motoneuron disorders, 56 patients with neuropathies, 71 patients with myopathies, and 34 controls). Two muscles from patients with neurogenic disorders were misclassified as "myopathic." Misclassification was more frequent only in myositis (4 of 28 muscles) and in oculopharyngeal muscular dystrophy (2 of 4 muscles). MUP discriminant classification was as sensitive as, and more specific than, conventional quantitative EMG, which discriminated between myopathic and neuropathic in only 22% of the muscles. This rate was 59% for discriminant analysis. As a knowledge-based expert system, MUP discriminant analysis successfully distinguishes between myopathic, neuropathic, and unclassifiable MUP samples. It discloses more information than conventional quantitative MUP analysis.

Action Potentials↗
PubMed1999

Cytokine mRNA expression in peripheral blood cells of immunosuppressed human islet transplant recipients.

The macrophage derived cytokines interleukin-beta (IL-1beta), and tumor necrosis factor alpha (TNFalpha), and the T-cell derived cytokine interferon gamma (IFNgamma) have been implicated to play an important role in early attack on islet cells during human islet transplantation (ITx). Therefore, the aim of this study was to investigate the influence of the current immunosuppressive induction therapy in clinical islet transplantation on mRNA expression of these cytokines in blood cells, compared to lipopolysaccharide (LPS) induced cytokine release in vitro and to plasma levels. The cytokine release correlated to lymphocyte counts and significantly decreased after ATG, and partially recovered 2 weeks after ITx. Unexpectedly, there was no correlation between mRNA expression for IL-1beta in total blood and the number of lymphocytes and monocytes remaining after anti thymocyte globulin (ATG)-therapy. Even when the blood was nearly totally depleted from mononuclear cells, high amounts of IL-1beta mRNA could be detected. However, IL-1beta secretion could not be stimulated in vitro. Our results show that application of ATG during ITx might contribute to graft survival during the early posttransplant period by suppression of the synthesis of monocyte derived cytokines IL-1beta and TNFalpha.

Antilymphocyte Serum↗
PubMed1999

Endotoxin-mediated activation of cytokine production in human PBMCs by collagenase and Ficoll.

Endotoxin-induced early inflammatory reactions may inhibit the function and survival of isolated cells or cell aggregates after transplantation. By the chromogenic Limulus amebocyte lysate assay we found rather high but variable endotoxin concentrations in the chemicals used for islet isolation, i.e. collagenase and Ficoll. Liberase, a special collagenase preparation from Boehringer, was nearly endotoxin-free. Correlating to the endotoxin content, collagenase and Ficoll had the capacity to induce interleukin-1beta release from human peripheral blood mononuclear cells. Because collagenase and density gradient media are needed in most cell isolation procedures from solid organs, each lot of these chemicals should be tested for endotoxin contamination. In pancreatic islet transplantation, the use of endotoxin-free chemicals may diminish early local inflammatory reactions at the graft site and thereby reduce the number of islets needed for successful islet transplantation.

Collagenases↗
PubMed1999

[Dysautonomia in Guillain-Barré syndrome].

About 20% of all GBS patients have symptoms of dysautonomia: labile hypertension, orthostatic hypotension, sinustachycardia or sinus arrest. This rate rises to 75% in patients with tetraplegia. Proprioceptive loss predicts dysautonomia independently from the severity of weakness. It is frequently responsible for dysautonomia. The afferent limb of cardiovascular regulation contains more myelinated fibers than the sympathetic and parasympathetic efferences, which determine the common classification of dysautonomia. The frequence of mixed sympathetic and parasympathetic hyperactivity is hard to explain by efferent lesions. Afferent conduction block releases the sympathetic efference of the baroreceptor reflex. The resulting catecholamine excess explains hypertension, tachycardia, ECG-changes and hyperglycemia. Norepinephrine sensitizes left ventricular stretch receptors. They induce cardiovascular depression and neurocardiogenic syncope which has a temporal behaviour similar to the blood pressure variations of GBS. Conduction block of sinoatrial stretch receptors causes inappropriate secretion of ADH and renin. Dysbalance between myelinated and unmyelinated afferents which decrease and increase heart rate may cause parasympathetic hyperactivity, as exemplified by pulmonary stretch receptors that are stimulated by artificial ventilation. Wrong afferent feedback is responsible for many cardiovascular instabilities in GBS. Blockade of misguided efferent reactions is an attractive therapeutical approach.

Autonomic Nervous System↗
PubMed1999

Indicators of dysautonomia in severe Guillain-Barré syndrome.

This study sought to establish quantitative criteria for dysautonomia in artificially ventilated patients with Guillain-Barré syndrome (GBS). Such criteria would help to identify patients at risk for cardiovascular complications. This retrospective controlled clinical study compared hourly cardiovascular monitoring data from 36 successive, artificially ventilated GBS patients with that from 11 artificially ventilated control patients with myasthenia. Tolerance limits for daily means, extremes, and variations in heart rate (HR) and blood pressure (BP) were estimated from the most abnormal subgroups of the treatment days of our control patients. These exceeded previously suggested arbitrary cutoff values for dysautonomia. The range in systolic BP was increased in 27 GBS patients, despite an upper limit of normal (85 mmHg) that was double the value suggested in previous work. All 16 patients with mean systolic BP above 165 mmHg also had persistent tachycardia (mean HR > 125 bpm), or were treated with beta-blockers. This pattern of sympathetic hyperactivity was combined with probable vagal hyperactivity (bradycardia < 48 bpm) in 6 patients. Hypotension (minimal systolic BP < 85 mmHg) and unprovoked bradycardia indicated sympathetic hypoactivity in 3 patients. Except in one patient who suffered from asystole on his first day on the ICU, all episodes of bradycardia were preceded by increased daily systolic BP variation (> 85 mmHg), which thus proved to be a sensitive and prognostically valuable indicator of dysautonomia in GBS.

Autonomic Nervous System Diseases↗
PubMed1998

Anti-Hu-associated paraneoplastic sensory neuropathy with peripheral nerve demyelination and microvasculitis.

A patient had a paraneoplastic autonomic, then sensory, then sensory-motor neuropathy with small cell lung carcinoma and a high titer Anti-Hu antibody to nuclei of neuronal cells. As an unusual finding there was electrophysiological and pathological evidence of demyelination and a peripheral nerve microvasculitis. The relationship of microvasculitis and peripheral nerve demyelination is discussed and their occurrence with paraneoplastic anti-Hu-associated sensory neuropathy is suggested not to be by chance.

Aged↗
PubMed1997

Prominent sensory ataxia in Guillain-Barré syndrome associated with IgG anti-GD1b antibody.

Sensitization with GD1b has been shown to cause sensory neuropathy in rabbit. A patient with chronic sensory-dominant polyneuropathy who had IgM antibody specifically to GD1b has been reported previously. This report describes the first patient with acute demyelinating polyneuropathy with prominent sensory symptoms who had a high titer of serum IgG anti-GD1b antibody. The serum reacted with neither GM1 nor with other b-series gangliosides (GD2, GD3, GT1b and GQ1b). Improvement in symptoms was coincident with decrease in IgG anti-GD1b antibody titer after plasmapheresis. This case supports the experimental results in rabbit suggesting that anti-GD1b antibody functions in the development of sensory ataxia.

Ataxia↗