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B Kurtz

Publications and source records attributed to B Kurtz.

At least 37 records · Page 2Linked to original sources
PubMed1988

[Renal involvement in malignant lymphoma: significance of imaging technics for determining spread].

Large autopsy series show an incidence of 33 to 62% of renal involvement in all patients with malignant lymphoma; at the time of diagnosis, this is found only very rarely. The present paper describes three patients with renal involvement at the time of diagnosis. The value of sonography, CT and angiography in detecting renal involvement and its clinical significance in the management of malignant lymphoma is discussed.

Adult↗
PubMed1987

[1st results of the diagnosis of focal liver and spleen lesions using gradient echo sequences].

15 healthy subjects and 39 patients with focal liver and spleen lesions were examined via MR tomography at 1.5 tesla. Gradient field echos at small angle excitation (less than 90 degrees) were employed. The imaging time per layer was 10 seconds so that rapid imaging could be carried out at respiratory standstill. This enabled visualisation of liver and spleen without interference by breathing artifacts and with accurate localisation. Focal lesions can be imaged best at low flip-angle pulses (liver) or low to medium-angle pulses (spleen). The primary liver cell carcinoma is visualised as an inhomogeneous structure with similar signal intensity as the surrounding tissue. All other examined liver lesions (metastases, haemangiomas, lymphatic infiltrates, echinococcus cysts, FNH, gummae) showed greater signal intensity than the remaining organ at small angle excitation. Furthermore, contrast reversals were seen at medium-angle pulses. Contrariwise, with the exception of the light-coloured spleen infarcts, spleen lesions (lymphatic infiltrate, Boeck's disease or sarcoidosis) appeared darker at all excitation angles than the surrounding tissue.

Humans↗
PubMed1987

[Focal changes in the spleen. Ultrasonic morphological characteristics and their clinical significance].

Focal changes in the spleen were rare findings in a large clinical material (less than 1% of cases). In a prospective study, which included 580 patients, lesions in the spleen were found in 40. Four focal lesions were due to infiltrates from non-Hodgkin's lymphoma. Twenty-one lesions with low echoes consisted of twelve infiltrates from Hodgkin's disease (six patients) or non-Hodgkin's lymphoma (six patients), five were due to fresh splenic infarcts and one each to an abscess, a metastasis from a carcinoma of the stomach, sarcoid and a haemorrhage. In only three of ten highly echogenic foci was a diagnosis possible (one leukaemic infiltrate and two scars following splenic infarcts). The significance of the sonographic demonstration of focal splenic lesions for diagnosis and treatment is discussed. The advantages of a sector scanner for evaluation of the spleen and splenic size are mentioned.

Hodgkin Disease↗
PubMed1987

[The internal echo pattern of the normal pancreas. An assessment of the aging process and body weight dependence by sonographic gray-scale analysis].

Sonography of the pancreas was evaluated quantitatively in 94 normal subjects. The grey-scale values in the head and body of the pancreas were measured and compared with those of retroperitoneal fat. The echogenicity of the pancreas and the contrast between pancreas and fat were correlated with the age and weight of the subjects. Semi-quantitative studies revealed a positive correlation between echogenicity and age (r = 0.505); this can be confirmed to a high degree of statistical significance by quantitative analysis of pancreatic grey-scale values (r = 0.55 for the head and 0.71 for the body). Further improved correlation with age is obtained by computing the sonographic contrast between the pancreas and the retroperitoneal fat (r = 0.66 for the head and 0.77 for the body of the pancreas). It is concluded that determination of the grey-scale value can provide additional information particularly if one uses retroperitoneal fat as a reference tissue.

Adipose Tissue↗
PubMed1987

Pharmacokinetics of phenoxymethyl penicillin (penicillin V) in calves.

Phenoxymethyl penicillin (penicillin V) was administered intravenously (i.v.) and orally to pre-ruminant calves and the distribution and elimination kinetics, as well as the oral bioavailability, were determined. After i.v. injection, the drug was distributed rapidly in the body, the elimination half-life (t1/2 beta) was 34 min and the apparent volume of distribution at steady-state (Vd ss) was 0.30 l/kg. Mean peak serum drug concentrations were directly related to the oral dose administered, i.e. 0.22 microgram/ml, 1.06 micrograms/ml and 2.14 micrograms/ml after dosing at 10, 20 and 40 mg/kg, respectively. The elimination t1/2 of the drug after oral dosing varied between 90 and 110 min, and the oral bioavailability was approximately 30% of the dose. The co-administration of phenoxymethyl penicillin and probenecid resulted in elevation and prolongation of serum drug concentration. The percentage of drug bound to serum proteins was 78.8% +/- 8.2%. Phenoxymethyl penicillin was probably inactivated and degraded in the gastrointestinal tract of 6-week-old calves fed exclusively hay, silage and concentrates as very low and erratic serum drug concentrations were measured after these calves were dosed orally with the drug at 40 mg/kg. In view of the narrow antibacterial spectrum of the drug and the relatively high dose required, it appears that phenoxymethyl penicillin can only be of limited practical value for the treatment of bacterial infections in preruminant calves.

Administration, Oral↗
PubMed1987

Clavulanate-potentiated amoxycillin: in vitro antibacterial activity and oral bioavailability in calves.

The minimal inhibitory concentrations (MIC) of amoxycillin and clavulanate-potentiated amoxycillin (amoxycillin:clavulanic acid, 4:1 by weight) were compared for 171 Salmonella, 170 Escherichia coli, and 32 Pasteurella isolates recovered from infected neonatal calves. In the presence of clavulanic acid, the MIC of amoxycillin was reduced to levels less than or equal to 12.5 micrograms/ml for all the Salmonella group B, all the Pasteurella, and for 12 out of the 44 E. coli isolates which were resistant to amoxycillin (MIC greater than or equal to 100.0 micrograms/ml). For isolates sensitive to amoxycillin (MIC less than or equal to 1.56 microgram/ml) there was no change in MIC values in the presence of clavulanic acid. A small proportion of Salmonella and E. coli isolates were resistant to clavulanate-potentiated amoxycillin. In a cross-over trial involving 10 preruminant (2 weeks old) calves, amoxycillin trihydrate and clavulanate-potentiated amoxycillin were administered orally at 10 mg/kg. An analysis of serum amoxycillin level data showed that the pharmacokinetic parameters t1/2ab, Cmax, t1/2 beta, AUC, Cp degree, and f' (estimated drug absorption ratio) were the same after treatment with amoxydrate and clavulanate-potentiated amoxycillin. Administration of clavulanate-potentiated amoxycillin and probenecid resulted in elevation and prolongation of serum amoxycillin levels. Computations showed that in preruminant calves serum amoxycillin concentrations sufficient to inhibit sensitive pathogens can be maintained by oral clavulanate-potentiated amoxycillin treatment at 10 mg/kg TID. At two times that dose rate serum drug concentrations capable of inhibiting 50% of all types of pathogens examined can be maintained.(ABSTRACT TRUNCATED AT 250 WORDS)

Amoxicillin↗
PubMed1987

Clinical pharmacokinetics of five oral cephalosporins in calves.

The minimal inhibitory concentrations (MIC) of cephalexin, cephradine, cefaclor, cefatrizine and cefadroxil for Salmonella species, Escherichia coli and Pasteurella multocida isolated previously from young calves were determined. The MIC90 values for cephalexin, cephradine and cefadroxil ranged between 3.12 micrograms ml-1 and 12.5 micrograms ml-1, whereas those of cefatrizine and cefaclor were 3.12 micrograms ml-1 and 0.78 microgram ml-1, respectively. Each drug was administered intravenously and orally to groups of pre-ruminating calves and orally to early ruminating calves. Although the pharmacokinetic characteristics of the drugs after intravenous injection were similar to other beta-lactam antibiotics, significant differences between the cephalosporins examined were found in respect of certain kinetic parameters. The drugs showed rapid absorption into the systemic circulation after oral administration to pre-ruminating calves but the elimination half-life values (t1/2 beta) varied between three hours (cefaclor and cefadroxil) and nine hours (cefatrizine). The bioavailability of the drugs was about 35 per cent of the administered dose. Co-administration of probenecid with each antibiotic caused a twofold or greater increase in peak serum drug concentrations (Cmax) but the effect on t1/2 beta was variable. Cephalexin, cephradine and cefaclor given to the ruminating calves resulted in very low serum or plasma concentrations and their use should be restricted to younger calves. Cefadroxil was found to give the highest serum concentrations in this age group but had significantly lower bioavailability when compared with the unweaned calves. Provisional oral dosage regimens were computed for each cephalosporin on the basis of the MIC data and the kinetic parameters derived from intravenous and oral drug administration.

Absorption↗
PubMed1986

[Value of rapid sequential computed tomography for the diagnosis of liver cirrhosis].

Thirty-eight patients with cirrhosis of the liver and thirty-seven controls were examined by dynamic computer tomography in a prospective study. Time-density difference curves for the liver, spleen, portal vein, aorta and vena cava were treated mathematically ('gamma fit'). Comparison of the values of the difference curves of liver, spleen and portal vein showed significantly lower and delayed peaks in patients with cirrhosis than in normal people. The time-density difference curves of the liver showed a highly significant shallow decline in the presence of cirrhosis. Discriminant analysis of the curve parameters using the spleen showed differentiation between normals and cirrhosis patients of 90.2%, and using the liver curve a separation of 83%. Combining these parameters of liver and spleen curves improved the separation between cirrhotic patients and normals to 94%.

Female↗
PubMed1986

[Dynamic CT of lymphoma manifestations of the liver and spleen].

Fourteen patients with lymphoma involving the liver and/or spleen were examined by dynamic CT. Lymphoma lesions show little enhancement with respect to the spleen and usually also when compared with liver tissue. On two occasions there was a definite increase in density during the arterial phase and dynamic CT could not distinguish the lesions from tumours of hepatic origin. One circumscribed lymphomatous lesion of the liver and six splenic infiltrates were only visible during the first few seconds after a bolus of contrast material had been injected. Dynamic CT does not usually differentiate diffuse involvement of the liver and spleen. In this situation, lack of a trabecular structure of the spleen during the arterial phase and a low peak of the time-density curve may suggest diffuse infiltration.

Adolescent↗
PubMed1986

[X-ray diagnosis of thoracic aorta ruptures].

One hundred and twenty-two patients were examined in order to diagnose, or for follow-up of, acute or chronic traumatic rupture of the thoracic aorta; sixty-two had arterial angiography, thirty-three had intravenous digital subtraction angiography, thirty-one had computer tomograms and seventeen were examined by ultrasound. In addition, plain films were evaluated in forty-two cases. The value of these methods in diagnosing acute or chronic aneurysms is analysed and discussed. Arterial angiography was the best method for acute aneurysms, whereas in the sub-acute and chronic stages CT and DSA are indicated.

Adolescent↗
PubMed1986

[Subjective evaluation and quantitative gray-scale analysis in the sonographic diagnosis of diffuse changes in the liver parenchyma].

Two investigators were asked to evaluate independently the echogenicity, coarsening and inhomogeneity of the hepatic echo pattern in a semi-quantitative manner; they had no knowledge of the diagnosis and used the same apparatus. The three subjective criteria were largely independent from the observer. Approximately three-quarters of all patients with slightly increased echogenicity showed a subjective appearance of coarsening; the impression of inhomogeneity increased significantly with increasing echogenicity. This is of importance in the sonographic evaluation of cirrhosis of the liver and in the diagnosis of diffuse liver metastases in a fatty liver. Grey scale analysis within a region of interest showed satisfactory correlation between the measured mean grey scale and echogenicity. Standard deviation within the grey scale was redundant, and there was no correlation between the other subjective characteristics and quantitatively measurable values.

Fatty Liver↗
PubMed1986

Clinical pharmacokinetics of flumequine in calves.

The minimal inhibitory concentration (MIC) of flumequine for 249 Salmonella, 126 Escherichia coli, and 22 Pasteurella multocida isolates recovered from clinical cases of neonatal calf diarrhoea, pneumonia and sudden death was less than or equal to 0.78 microgram/ml. The pharmacokinetics of flumequine in calves was investigated after intravenous (i.v.), intramuscular (i.m.) and oral administration. The two-compartment open model was used for the analysis of serum drug concentrations measured after rapid i.v. ('bolus') injection. The distribution half-life (t1/2 alpha) was 13 min, elimination half-life (t1/2 beta) was 2.25 h, the apparent area volume of distribution (Vd(area)), and the volume of distribution at steady state (Vd(ss)) were 1.48 and 1.43 l/kg, respectively. Flumequine was quickly and completely absorbed into the systemic circulation after i.m. administration of a soluble drug formulation; a mean peak serum drug concentration (Cmax) of 6.2 micrograms/ml was attained 30 min after treatment at 10 mg/kg and was similar to the concentration measured 30 min after an equal dose of the drug was injected i.v. On the other hand, the i.m. bioavailability of two injectable oily suspensions of the drug was 44%; both formulations failed to produce serum drug concentrations of potential clinical significance after administration at 20 mg/kg. The drug was rapidly absorbed after oral administration; the oral bioavailability ranged between 55.7% for the 5 mg/kg dose and 92.5% for the 20 mg/kg dose. Concomitant i.m. or oral administration of probenecid at 40 mg/kg did not change the Cmax of the flumequine but slightly decreased its elimination rate. Flumequine was 74.5% bound in serum. Kinetic data generated from single dose i.v., i.m. and oral drug administration were used to calculate practical dosage recommendations. Calculations showed that the soluble drug formulation should be administered i.m. at 25 mg/kg every 12 h, or alternatively at 50 mg/kg every 24 h. The drug should be administered orally at 30 and 60 mg/kg every 12 and 24 h, respectively. Very large, and in our opinion impractical, doses of flumequine formulated as oily suspension are required to produce serum drug concentrations of potential clinical value.

Administration, Oral↗