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J Schäffer

Publications and source records attributed to J Schäffer.

At least 19 recordsLinked to original sources
PubMed2001

Scintigraphic methods to detect beta2-microglobulin associated amyloidosis (Abeta2-microglobulin amyloidosis).

beta2-Microglobulin-derived amyloidosis (Abeta2m) represents a major cause or morbidity in patients with end-stage renal disease. Symptoms of Abeta2m amyloid are mainly related to (peri-) articular amyloid deposition. Conventional non-invasive diagnostic techniques, i.e. clinical evaluation, joint ultrasonography or X-ray, computed tomography or magnetic resonance imaging findings, as well as conventional bone scans, suffer from relative non-specificity and/or low sensitivity. Two recent methods, namely scintigraphy with radiolabelled serum amyloid P component (SAP) or with the radiolabelled Abeta2m-precursor protein, beta2-microglobulin (beta2m), yield more specific information. Using (123)I-labelled SAP, Abeta2m deposits have been visualized in several long-term haemodialysis (HD) patients. However, this scan did not show tracer accumulation in other frequently involved sites, such as hips or shoulders, but did frequently label the spleen, which is usually spared from Abeta2m deposits. Scanning with (131)I-labelled beta2m, in contrast, yielded tracer accumulations corresponding to the typical distribution pattern of Abeta2m. Specificity of this method was shown by several methods, and the sensitivity was found to markedly exceed that of combined clinical and radiological investigations. Recently, both the radiation exposure and the optical resolution of this latter scan have been further refined by substituting (131)I with (111)In. In a final step we generated recombinant human beta2m (rhbeta2m). (111)In-rhbeta2m again failed to show significant tracer accumulation over joint regions in patients on short-term HD without evidence of Abeta2m amyloidosis. In contrast, local tracer accumulations similar to those observed with natural, (111)In-labelled beta2m could be demonstrated in long-term HD patients with evidence of Abeta2m amyloidosis. In conclusion, scintigraphy for Abeta2m with (111)In-labelled rhbeta2m provides a homogenous and safe recombinant protein source, and allows for the sensitive and specific non-invasive detection of Abeta2m-amyloid deposits in dialysis patients.

Amyloidosis↗
PubMed2001

[The Hannover School of Veterinary Medicine in the Third Reich. Part 1: early history, assumption of power and consolidation of the Nazi regime].

During the time of the Weimar republic the professors and students at the School of Veterinary Medicine Hannover had a national-conservative political attitude with a clearly anti-republican tendency. Before 1933 the National Socialism did not play a role at the school. After the assumption of power by Hitler the 'Gleichschaltung'--which also took place at the universities--ran mostly smoothly at the veterinary school. 75% of the teaching staff and 50% of the students had joined the NSDAP (nazi party) respectively the NSDStB (nazi student organisation) at the end of the summer semester 1933. The following development of the school until World War II is closely connected with the foundation of the Military Veterinary Academy in Hannover in 1935. During the years 1935-1939 offerings were made in a traditional way and without political considerations playing a major role. With the beginning of World War II the school developed into the centre of veterinary studies in Germany. In order to meet the demand of veterinary officers and civil veterinarians the studies were shortened, trimesters were temporarily introduced und standards of examinations were lowered. At the end of the war around 45% of the school was destroyed. In the beginning the denazification meant a significant turning point but it developed into a mere episode of the history of the school by the reappointment of all the seven professors who had been dismissed in 1945/46.

Education, Veterinary↗
PubMed2001

[Armourer and mad cow disease: images of veterinarians in music].

This contribution is not about animals in music; it rather attempts to describe how veterinary medicine as a discipline and veterinarians as representatives of the profession are perceived of and portrayed in music. Aside from Gioacchino Rossini's "Barber of Seville", in which Count Almaviva impersonates a veterinarian of the day, the most sympathetic veterinarian character ever created by a lyricist or composer in surely Hans Stadinger, the "armourer" and vet in Albert Lortzings opera. In other musical genres such as artsongs and folksongs, the only such figure worthy of musical interpretation seems to have been those masters of the fiery forge who were also wise in the veterinary healing arts. In the past 20 years vets and veterinary medicine have been included in new musical trends: There are musicals and radio plays in which even the youngest members of the audience are exposed to the veterinarian profession. A number of pop groups are also to be mentioned here. For example, animal welfare has been thematized by punk rockers, and a pop group for Hamburg has put a medieval horse blessing to music. Last but not least, a number of vets in Berlin turn their everyday troubles and worries into musical parodies.

Animals↗
PubMed2000

Recombinant versus natural human 111In-beta2-microglobulin for scintigraphic detection of Abeta2m amyloid in dialysis patients.

BACKGROUND: We previously introduced scintigraphy with 131I-labeled beta2-microglobulin (beta2m), purified from uremic hemofiltrate, that is, "natural" beta2m, to specifically detect beta2m-associated amyloidosis (Abeta2m) in hemodialysis (HD) patients. METHODS: To improve the safety and resolution of the scan, we covalently bound the chelator diethylenetriaminepentaacetic acid to natural beta2m to allow radiolabeling with 111In. In a second step, we generated and evaluated the usage of recombinant human beta2m (rhbeta2m) for scintigraphy. RESULTS: Using natural 111In-labeled beta2m, eight patients on HD for 0 to 17 years, without evidence of Abeta2m, were scanned. Whole-body scintigraphy at 48 to 72 hours postinjection revealed no significant tracer accumulation over joint regions. In contrast, nine patients on HD for 10 to 21 years with clinical, radiological, or histologic (N = 4) evidence of Abeta2m showed selective tracer uptake over various joint regions. Tracer accumulation in visceral organs, which could not be related to tracer elimination or metabolism, was not detected. Compared with the previous 131I beta2m scan, scintigraphy with 111In-labeled beta2m offered highly improved image contrast, increased sensitivity, and a 50 to 70% reduction of the radiation exposure. Scanning with 111In-labeled recombinant human beta2m was performed in six patients: No significant tracer accumulation was observed over joint regions in two patients on short-term HD without evidence of Abeta2m; in contrast, local tracer accumulations similar to those observed with natural beta2m could be demonstrated in four long-term (10 to 27 years) HD patients with clinical, radiological, and histologic (N = 1) evidence of Abeta2m. CONCLUSION: Scintigraphy for Abeta2m with 111In-labeled rhbeta2m provides a homogenous and safe recombinant protein source and leads to enhanced sensitivity and lower radiation exposure.

Adult↗
PubMed2000

Role of endogenous nitric oxide in circadian blood pressure regulation in healthy humans and in patients with hypertension or atherosclerosis.

BACKGROUND: Nitric oxide (NO) is involved in the regulation of blood pressure and local blood flow. Its biological activity is impaired in hypertension and atherosclerosis. Because blood pressure undergoes a circadian rhythm, we investigated whether systemic NO production is dependent on a circadian variability, and whether the phasing of diurnal rhythm in NO production corresponds to the one in blood pressure in humans. METHODS: We studied three groups of human subjects: 8 healthy volunteers (HV), 8 patients with essential hypertension (HT), and 8 patients with peripheral arterial occlusive disease (PAOD). Twenty-four-hour ambulatory blood pressure monitoring was performed simultaneously with eight consecutive 3-hour urine collection periods. Urinary nitrate excretion was measured by gas chromatography-mass spectrometry; urinary cyclic GMP excretion was assessed by RIA. RESULTS: Twenty-four-hour mean arterial blood pressure was 119.8 +/- 2.0/75.8 +/- 1.5 mm Hg in HV, 145.0 +/- 6.4/94.9 +/- 2.8 mm Hg in HT (P < 0.05 vs HV), and 137.0 +/- 7.3/81.5 +/- 1.9 mm Hg in PAOD (P = NS vs HV). There was significant circadian variation in blood pressure in all groups, but daily amplitude was lower in HT and PAOD than in HV (P < 0.05); 24-hour mean urinary nitrate excretion was 183.4 +/- 27.2 mumol/mmol creatinine in HV, 102.9 +/- 18.1 mumol/mmol creatinine in HT, and 162.1 +/- 22.2 mumol/mmol creatinine in PAOD (P < 0.05 vs HV and HT). Urinary cyclic GMP excretion was 211.8 +/- 19.0 nmol/mmol creatinine in HV, 108.6 +/- 12.4 nmol/mmol creatinine in HT, and 97.9 +/- 13.4 nmol/mmol creatinine in PAOD (P < 0.05 for HT and PAOD vs HV). Circadian variation was present in urinary nitrate and cyclic GMP excretion in HV but was significantly diminished in HT and PAOD, respectively; 24-hour mean nitrate-to-cyclic GMP ratio was 0.89 +/- 0.05 in HV and 1.10 +/- 0.10 in HT (P = NS). It was increased to 2.02 +/- 0.17 in PAOD (P < 0.05 vs HV and HT). CONCLUSIONS: There is significant circadian variation in urinary nitrate and cyclic GMP excretion rates, two marker molecules for systemic NO production, in healthy humans. NO production is increased in the morning, concomitantly with the morning increase in blood pressure, indicating that NO may buffer blood pressure increase. Diurnal variation in nitrate and cyclic GMP excretion is absent in HT, pointing to impaired NO formation. The major change in PAOD is increased nitrate/cyclic GMP ratio, which points to increased oxidative inactivation of NO in this disease. Disturbed formation and activity of NO may contribute to blood pressure alterations in cardiovascular disease.

Adult↗
PubMed2000

[Legislation of ritual slaughtering in Germany since 1933].

The article surveys the development of legislation to the slaughtering of warm-blooded animals in Germany since 1933. It examines the ritual slaughtering of the Jews (Schechita) on the one hand, and of the Moslems (Dabh) on the other hand. While 1933 the legislation was coined by the political situation, after 1949, legal setting and decisions reflected the changing sensibility to animals' protection. Before 1945, Schechita was the matter of legal dispute, more recently, the discussion has centred on the ritual slaughtering of the Moslems, with different arguments. The "Law on the Slaughtering of Animals" of 21-04-33 was part and parcel of the Third Reich's policy against Jews implicating a nation wide practical inhibition of Schechita by decreeing a general obligation of stunning before slaughtering. In 1945, the inhibition of Schechita became invalid after the occupation of the Reich by the Allied Forces. For the first time, the "First Amendment to the Animal Protection Law" of 1986 permitted ritual slaughtering by the way of exception as long as it was covered by the religious obligations. In 1995 the Federal Administrative Court judged that an inhibition of the ritual slaughtering by Moslems could be possible, because there are no religious obligations for Moslems. Nowadays, the ritual slaughtering of the Moslems is, de facto, forbidden, Schechita is performed in some cities for the needs of the residential Jewish population.

Abattoirs↗
PubMed2000

Detection of significant renal artery stenosis with color Doppler sonography: combining extrarenal and intrarenal approaches to minimize technical failure.

BACKGROUND: Renal artery disease can cause both hypertension and renal failure, and color Doppler sonography (CDS) may be a good screening method to detect it. Presently reported techniques of Doppler sonography have either a high rate of technical failure (4-42%), or low sensitivity and specificity, or detect only stenoses greater than 70%, or exclude patients with renal failure from analysis. In previous studies Doppler detection of renal artery stenosis (RAS) was based either on increased intrastenotic velocity or on the detection of post-stenotic Doppler phenomena. In the present prospective study these two approaches were combined to detect RAS (> or = 50% diameter reduction) in 226 consecutive patients (144 with normal and 82 with impaired renal function). METHODS: Stenosis of 50% or more was diagnosed if the maximal systolic velocity in the main renal artery was more than 180 cm/sec and velocity in the distal renal artery less than one quarter of the maximum velocity. When these velocities could not be determined a diagnosis of RAS was made when the acceleration time in intrarenal segmental arteries exceeded 70 msec. All patients subsequently underwent arteriography as the gold standard for the detection of RAS. RESULTS: With this combined approach, the technical failure rate of CDS was 0% in both patients with normal and those with impaired renal function. The mean time required for the Doppler investigation was 17 minutes. The sensitivity and specificity for detection of a significant stenosis in a given vessel (including accessory arteries), as compared to angiography, were 96.7% and 98.0%. CONCLUSION: Color Doppler sonography, evaluating both main renal and intrarenal arteries is an ideal screening method for detection of RAS of 50% or more because it allows accurate and rapid detection of stenosis in all patients, irrespective of renal function.

Blood Flow Velocity↗
PubMed1999

Asymmetric dimethylarginine plasma concentrations differ in patients with end-stage renal disease: relationship to treatment method and atherosclerotic disease.

Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of endothelial nitric oxide (NO) synthase. Its concentration is elevated in patients with end-stage renal disease (ESRD), in part because it is excreted via the kidneys. In this study, the plasma concentrations of ADMA, symmetric dimethylarginine, and L-arginine were determined in relation to plasma nitrate levels (as an index of NO formation) for a group of 80 patients with ESRD. The effects of two treatment methods, i.e., hemodialysis (HD) and peritoneal dialysis (PD), and the role of the presence of atherosclerotic disease were evaluated. Forty-three patients receiving HD and 37 patients receiving PD were compared with healthy control subjects. Plasma L-arginine and dimethylarginine levels were determined by HPLC, using precolumn derivatization with o-phthaldialdehyde. Plasma nitrate levels were determined by gas chromatography-mass spectrometry. Predialysis ADMA concentrations in HD-treated patients were approximately sixfold higher than those in the control group (6.0+/-0.5 versus 1.0+/-0.1 micromol/L; P < 0.05). Plasma nitrate concentrations were significantly lower in HD-treated patients, which suggests that ADMA may inhibit NO synthase. In contrast, plasma ADMA levels and nitrate concentrations in PD-treated patients were similar to those in control subjects. Plasma L-arginine concentrations were not significantly decreased in patients with ESRD. ADMA concentrations were significantly decreased 5 h after HD, compared with baseline values. ADMA levels were significantly higher in HD-treated patients with manifest atherosclerotic disease than in HD-treated patients without atherosclerotic disease (7.31+/-0.70 versus 3.95+/-0.52 micromol/L; P < 0.05). This study confirms that ADMA is accumulated in ESRD. PD-treated patients exhibit significantly lower ADMA levels than do HD-treated patients. Accumulation of ADMA may be a risk factor for the development of endothelial dysfunction and cardiovascular disease in patients with ESRD.

Adult↗
PubMed1999

[Abil-ilisu--a "cattle doctor" in Babylonia (circa 1739 B.C.)].

Since decades the search for the first "veterinarians" in Ancient Mesopotamia and Egypt known by name is accompanied by speculations. Both Ur-Lugal-edinna from Lagash and the Sekhmet-priest Aha-Nakht turned out to be a specific historical fiction. Terminologically assured records for the terms "cattle-doctor" and "donkey-doctor" were found not before about 1800 in Old Babylonian documents and laws. Samsu-iluna, successor to Hammurapi, ruled from 1749-1712. Out of this time there exists a court record that mentions an "a.zu gu4.hi.a", a 'cattle-doctor', factually by his name. This document drawn up in Sippar names Abil-ilisu as one of altogether seven witnesses of a plaintiff that demands his right for restitution (TD 132, AO 2708).

Animals↗
PubMed1996

[Prof. Dr. Richard Völker and the School for Veterinary Medicine Technical Assistants in Hannover].

The first assistant professions in medicine technical field were established in the last third of the 19th century. Basic units primarily were private institutions which aimed to set up training facilities and money-making opportunities for unmarried women of the middle and upper classes. In correlation with the progress in microbiology and X-ray technics from about 1900 in veterinary medicine the demand for technical assistants raised up too. Since 1929 in some institutes and clinics of the Hannover Veterinary School unpaid trainees were instructed. Accordingly to this the "School for the Training of Technical Assistants in Veterinary Institutes" was founded on the initiative and under control of Richard Völker in summer 1937. In this paper a preliminary report is given which deals with the main aspects of the development of the profession, the school's foundation history and the special role of its founder Völker. A doctoral thesis to this subject is submitted to the veterinary authorities.

Animal Technicians↗
PubMed1996

["Born from the flank"--discussion concerning "cesarean section" in animals in the Talmud].

The origins of the performance of Caesarean section on living animals are not established. In the Talmud, the term "jose dofèn" (delivered by way of the flank, or delivered through the lateral abdominal wall) is mentioned several times, referring specifically to the performance of Caesarean section. The 7th century Babylonian Talmud however has the tracts Bechoroth (Firstlings) and Chullin (About profane slaughter). The biblical background can be found in Exodus 13,2, where The Lord speaks to Moses: "Declare the first-born of man and beast to be holy to God". This Commandment is discussed at length in the Talmud, where two references to unnatural delivery are to be found. The first, how to evaluate a live, or dead, foetus that is found during the ritual slaughter of a healthy animal, or on the emergency slaughter of a fatally injured animal, that has to be cut out by incisions through the abdominal wall and the uterus (cf. Digest. XI, 8, 2 of Justinian). The second, how to evaluate a foetus that has to be delivered by embryotomy as a consequence of dystocia. It is believed that, contrary to previous opinions in the History of Veterinary Medicine, there is no evidence of the performance of Caesarean section on living animals in the Talmud.

Animals↗
PubMed1995

[Not Available].

Explore the source record for details and available documents.

Animals↗
PubMed1994

[Esmolol as a bolus for prevention of sympathetic adrenergic reactions following induction of anesthesia].

In addition to laryngoscopy, endotracheal intubation, and other stressful intraoperative phases, hypertension occurs during recovery from anaesthesia, provoking post-operative complications like bleeding and increased intracranial or intraocular pressure. Furthermore, these hypertensive reactions result in life-threatening complications, especially in patients with pre-existing cardiovascular diseases. In this study, the effect of the new, short-acting beta-blocker esmolol given as a single bolus for preventing the increases in blood pressure and heart rate during recovery from anaesthesia and extubation in patients with hypertension was investigated. PATIENTS AND METHODS. Sixty-three patients with a history of hypertension over a period of more than 6 months and blood pressure (BP) more than 150/90 mm Hg undergoing intervertebral-disc, otolaryngologic, or eye surgery were included in the study. The operations were performed during thiopentone-induced isoflurane anaesthesia with relaxation by atracurium. The patients were assigned to three groups after giving witnessed oral informed consent. During the study period they received the study drug twice: (A) 30-90 s before turning off the nitrous oxide; and (B) 20-90 s before extubation. Group I (placebo) received placebo each time, group II (100 mg esmolol) placebo at A and 100 mg esmolol i.v. at B, and group III (200 mg esmolol) 100 mg esmolol i.v. each time. After each medication the cardiovascular parameters were measured noninvasively over a period of 10 min every minute and in the following 2 h every 15 min. RESULTS. After the first medication systolic and diastolic BP, heart rate (HR), and rate-pressure product (RPP) were lower in patients receiving 100 mg esmolol (Group III) than in groups I and II. After the second injection the blood pressure was lower in the two groups receiving 100 mg esmolol, than the placebo group (I: 180.1 +/- 7.4/100.7 +/- 3.6; II: 152.8 +/- 5.8/87.9 +/- 3.4; III: 157.9 +/- 5.3/91.5 +/- 3.6 mm Hg [mean 2 min +/- SEM]). The changes in HR (I: 88.2 +/- 3.8; II: 75.6 +/- 2.6; III: 72 +/- 3.1 min-1) and RPP (I: 15,800 +/- 900; II: 11,700 +/- 700; III: 11,400 +/- 600) were similar. In 8 of the 20 patients in group III the HR dropped below 60.min-1, but in none of these patients did the BP become instable. CONCLUSIONS. The sympathoadrenergic reaction during recovery from anaesthesia and extubation can be treated by beta-blocking agents, but such therapy is not without risk because of the long half-life and effects of the therapy on other factors such as postoperative loss of intravascular volume. Esmolol is a new, short-acting, cardioselective beta-blocker with a very short plasma distribution time and a elimination half-life of 9.2 min. Thus, the potential risks of beta-blockers due to half-life are minimised. The results of this study show that a dangerous increase in BP and HR with increased myocardial oxygen consumption can be prevented by a single bolus, and better by a double bolus of 100 mg esmolol. Although bradycardia with HR below 50.min-1 in 8 patients might indicate a risk of cardiac instability, the systolic BP did not fall below 100 mm Hg, and the episode of bradycardia was so short that there was no risk to the patients.

Adrenergic beta-Antagonists↗