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C Hoffmann

Publications and source records attributed to C Hoffmann.

At least 73 records · Page 4Linked to original sources
PubMed1999

Expanded polytetrafluoroethylene threads for lip augmentation induce foreign body granulomatous reaction.

Especially in cases of facial aesthetic surgery, the demands of the patients are high. The formation of a visible and painful nodule will cause not only discomfort but also dissatisfaction. When alloplastic materials are used for facial and lip augmentation, the possibility of migration, allergic reaction, and formation of a foreign body granuloma is always present. Although e-PTFE is the most bioinert alloplastic material available, the authors could show the formation of a foreign body granuloma. When using e-PTFE threads for facial augmentation, the surgeon should keep in mind and inform the patients that the threads can induce a foreign body granulomatous reaction.

Adult↗
PubMed1999

Malignant tumor of the distal part of the femur or the proximal part of the tibia: endoprosthetic replacement or rotationplasty. Functional outcome and quality-of-life measurements.

BACKGROUND: The present study was performed to determine whether there is a difference, with regard to functional outcome and quality of life, between endoprosthetic replacement and rotationplasty for the treatment of malignant tumors of the distal part of the femur or the proximal part of the tibia. METHODS: Sixty-seven patients, between the ages of eleven and twenty-four years at the time of the diagnosis, had a malignant tumor of the distal part of the femur or the proximal part of the tibia. A rotationplasty was performed in thirty-three patients, and an endoprosthetic replacement was done in thirty-four patients. The median duration of follow-up was six years and one month (range, two years to sixteen years and two months). The scale developed by the Musculoskeletal Tumor Society was used to evaluate the functional results. Quality-of-life issues were assessed with the questionnaire developed by the European Organization for Research and Treatment of Cancer. RESULTS: The patients who had had a rotationplasty had a mean functional score, according to the system of the Musculoskeletal Tumor Society, of 24 points, and the patients who had had an endoprosthetic replacement had a mean score of 25 points. This difference was not found to be significant, with the numbers available (p = 0.47). Only one patient who had had a rotationplasty used an assistive device when walking long distances, whereas six patients who had had an endoprosthetic replacement used an assistive device. This difference was significant (p<0.001). The quality-of-life questionnaire revealed that the patients who had had a rotationplasty could participate in hobbies such as carpentry and sports as well as in other daily activities to a significantly greater degree than those who had had an endoprosthetic replacement (p = 0.001). Restriction in daily activities due to pain was significantly less common in the group that had had a rotationplasty than it was in the group that had had an endoprosthetic replacement (p = 0.047). CONCLUSIONS: Rotationplasty was not associated with any disadvantages with regard to function or quality of life in comparison with endoprosthetic replacement. It is possible that the psychosocial outcome is influenced by the fact that patients who have a rotationplasty know that additional operative intervention is not usually necessary. Despite good functional and quality-of-life results, the cosmetic appearance may be the most serious disadvantage of rotationplasty. The decision to perform this procedure must be made on a case-by-case basis.

Adolescent↗
PubMed1999

Parallel Synthesis and Testing of Catalysts under Nearly Conventional Testing Conditions.

Acceleration by one to two orders of magnitude for catalyst development without much loss of information: Parallelized synthesis and screening has been used to evaluate catalysts for the room-temperature oxidation of CO. The overall process was highly reproducible, and the data quality is comparable to that of conventional testing. The graph shows the results of parallel testing of Au/Co(3)O(4) catalyts at 25 degrees C (y=yield of CO(2)).

Journal Article↗
PubMed1998

Highly active antiretroviral therapy significantly improves the prognosis of patients with HIV-associated progressive multifocal leukoencephalopathy.

OBJECTIVE: To evaluate the impact of different antiretroviral therapies on the prognosis of AIDS patients affected by progressive multifocal leukoencephalopathy (PML). METHODS: A retrospective analysis of all HIV-infected patients admitted to hospital between 1988 and 1996 found 29 patients (25 men) with histologically or PCR-confirmed PML. Their mean age was 39.3 years. The median CD4 cell count was 40 x 10(6)/l (mean, 106 x 10(6)/l). Six patients had CD4 cell counts > 200 x 10(6)/l. Fourteen patients never received or stopped antiretroviral therapy following diagnosis (group A), 10 patients were treated with nucleoside analogues alone (group B), and five patients started highly active antiretroviral therapy (HAART) including protease inhibitors (group C). RESULTS: The median survival following the onset of symptoms was 131 days, but differed significantly between the three groups: group A, 127 days; group B, 123 days; group C, > 500 days (P < 0.0002 for the difference between group C versus group A and B, stratified log-rank test). As of July 1997, four out of five patients on HAART were still alive 391, 500, 543, and 589 days after diagnosis of PML and have either experienced a resolution of the symptoms (three patients) or had progressed very slowly (one patient). A multivariate analysis using Cox regression found younger age at diagnosis to be the only other variable associated with improved survival (P < 0.02). CD4 cell count, gender, prior AIDS diagnosis, mode of HIV transmission, and therapy with foscarnet, cytarabine, or interferon-alpha did not affect survival in this cohort (P > 0.1). CONCLUSION: This study of a large cohort of patients with confirmed PML indicates that AIDS patients with PML may benefit significantly from HAART. All patients with PML should be offered optimal antiretroviral combination therapy.

Acquired Immunodeficiency Syndrome↗
PubMed1998

Chromosome structure and human immunodeficiency virus type 1 cDNA integration: centromeric alphoid repeats are a disfavored target.

Integration of retroviral cDNA into host chromosomal DNA is an essential and distinctive step in viral replication. Despite considerable study, the host determinants of sites for integration have not been fully clarified. To investigate integration site selection in vivo, we used two approaches. (i) We have analyzed the host sequences flanking 61 human immunodeficiency virus type 1 (HIV-1) integration sites made by experimental infection and compared them to a library of 104 control sequences. (ii) We have also analyzed HIV-1 integration frequencies near several human repeated-sequence DNA families, using a repeat-specific PCR-based assay. At odds with previous reports from smaller-scale studies, we found no strong biases either for or against integration near repetitive sequences such as Alu or LINE-1 elements. We also did not find a clear bias for integration in transcription units as proposed previously, although transcription units were found somewhat more frequently near integration sites than near controls. However, we did find that centromeric alphoid repeats were selectively absent at integration sites. The repeat-specific PCR-based assay also indicated that alphoid repeats were disfavored for integration in vivo but not as naked DNA in vitro. Evidently the distinctive DNA organization at centromeres disfavors cDNA integration. We also found a weak consensus sequence for host DNA at integration sites, and assays of integration in vitro indicated that this sequence is favored as naked DNA, revealing in addition an influence of target primary sequence.

Binding Sites↗
PubMed1998

Relative bioavailability of rapidly dispersing, plain, and microencapsuled acetylsalicylic acid tablets after single dose administration.

UNLABELLED: Extent and rate of absorption of acetylsalicylic acid (ASA) from rapidly dispersing (Acesal Extra) and plain tablets (Acesal) relative to reference 1 (plain tablets, Aspirin) and from microcapsuled tablets (Micristin) relative to comparable listed tablets (reference 2, Colfarit) were assessed in 2 single-dose (0.5 g ASA), open, randomized, crossover studies with intervals of 14 days between 2 periods. Both studies were performed in 24 male and female healthy volunteers each (age 18-32 years, body weight 48-90 kg, body height 161-190 cm). ASA and its metabolite salicylic acid (SA) were measured with an HPLC method validated for ASA between 0.2 and 20 microg/ml and for SA between 0.4 and 40 microg/ml. The test tablets were considered bioequivalent with reference in extent of absorption if the 90% confidence limits of the AUC0 to infinity ratio were within the range of 0.80-1.25, and in rate of absorption if the confidence limits of the Cmax/AUC0 to infinity ratios were within 0.70-1.43. RESULTS: Geometric means and 90% confidence limits for the test/reference ratios of the comparisons Acesal vs reference 1, Acesal Extra vs reference 1 and Micristin vs reference 2 were 1.05 (0.97-1.13), 1.13 (1.05-1.22), 1.02 (0.92-1.14) for ASA AUC0 to infinity and 1.02 (0.96-1.07), 1.05 (0.99-1.11), 0.98 (0.91-1.04) for SA AUC0 to infinity, respectively. The results for Cmax/AUC of ASA were 1.16 (1.00-1.34), 1.72 (1.49-1.99), 0.83 (0.73-0.94) and of SA 1.02 (0.98-1.07), 1.07 (1.02-1.12), 0.93 (0.88-0.97). CONCLUSION: Acesal and Micristin were bioequivalent with the respective references in both extent and rate of absorption. Acesal Extra and reference 1 were bioequivalent with regard to extent only. Acesal Extra was absorbed faster.

Adult↗
PubMed1998

[Inverted Y partial ureteral duplication. Apropos of an unusual case].

Inverted Y partial ureteric duplication corresponds to the presence of a variable length of duplicated ureter before entering the bladder in an orthotopic or ectopic position. A case od inverted Y partial ureteric duplication with ureteric confluence in the hilum of the kidney associated with anastomosis of an ectopic ureter in the epididymis is reported. The description of this original case is compared with the data of the literature.

Adult↗
PubMed1998

[Laparoscopic cholecystectomy as routine intervention in acute cholecystitis].

The laparoscopic cholecystectomy has become the gold standard in the therapy of gall bladder stones in the last few years. The most contraindications of the first period of the laparoscopic era had been eliminated by the development of laparoscopic technique and growing experience. Since September 1995 the laparoscopic cholecystectomy has been established as routine procedure also for acute cholecystitis. From September 1995 to Dezember 1996 177 laparoscopic cholecystectomies were performed, 132 for symptomatic cholecystolithiasis and 45 for acute cholecystitis. Postoperative complications occurred in 8.3% in the elective group and in 8.8% in the acute cholecystitis group. There was no death in both groups. Patients left the hospital on day 3 (range 2-21) in the elective group, on day 4 (1-13) in the acute colecystitis group. There are no statistically significant differences. According to our results acute cholecystitis does not increase postoperative morbidity and mortality after laparoscopic cholecystectomy and has to be a contraindication for this method no longer.

Acute Disease↗
PubMed1998

[Value and sensitivity of abdominal ultrasound in preoperative histologic diagnosis before laparoscopic cholecystectomy].

In a retrospective study we compared the findings of our abdominal ultra-sound diagnostic of the gallbladder and the common bile duct with the results ot preoperative ERCP, intraoperative findings and the histological results. The test parameters were the size of the gallbladder, the number and the size of biliary calculi, the thickness and the constitution of the wall of the gallbladder and the consecutive grade of inflammation, the wideness of the common bile duct and the suspicion of a choledocholithiasis, respectively. In acute cholecystitis we performed laparoscopic cholecystectomy within 24 hours, in symtomatic cholecystolithiasis without cholecystitis an elective laparoscopic cholecystectomy. If there was suspicion of a choledocholithiasis we performed a preoperative ERCP. Altogether we had correct findings of the common bile duct in our ultrasound diagnostic in 133 of 136 cases (97.8%), only in 3 of 136 cases (2.2%) we had false negative ultrasound findings. With a generous indication to ERCP caused by anamnestic and/or laboratory findings the obstruction of the bile duct could be diagnosted and eliminated in 2 of these 3 cases preoperatively. In all cases of bile duct dilatation (7 mm and more) we found an obstruction of the common bile duct. Our results demonstrate that abdominal ultrasound is a high-efficiency method in the preoperative diagnostic of gallbladder and common bile duct stones.

Cholangiopancreatography, Endoscopic Retrograde↗
PubMed1997

The impact of intraoperative brachytherapy on surgery of Ewing's sarcoma.

Surgery of Ewing's sarcoma sometimes results in an inadequate surgical margin. The influence of intraoperative brachytherapy on local control of the tumor, operation time, blood loss, and surgical complications was evaluated, comparing the results of 20 patients who received brachytherapy to a series of 42 patients receiving surgery without brachytherapy. The dose of intraoperative brachytherapy ranged between 9 Gy and 21 Gy. The average operation time was longer in 20 cases with brachytherapy (7.9 h) than in 42 cases without brachytherapy (4.3 h) (P < 0.0001). The average blood loss in the groups with (3531 ml) and without brachytherapy (3515 ml) was comparable (P = 0.3840). The surgical complication rate in patients receiving brachytherapy was also similar to that of untreated patients (30% versus 31%, P = 0.7690). Local relapse developed in 1 of 20 patients who received brachytherapy and 1 of 42 patients without brachytherapy. On the basis of this analysis, it can be concluded that this procedure is safe and does not increase of the acute complication rate. The latest results of local controls are awaited.

Adolescent↗
PubMed1997

Surgical complications after preoperative irradiation of Ewing's sarcoma.

The influence of preoperative irradiation on surgical complications in 42 patients with Ewing's sarcoma was analysed. After preoperative irradiation and chemotherapy, 35 of 40 patients showed a good histological response and 25 of 40 patients had no viable tumour cells in the resected specimen. Local relapse alone did not develop, local relapse and metastasis developed in 2 patients and metastasis alone in 15 patients. Surgical complications appeared in 12 of 42 patients: 9 of 19 central tumours (19 pelvic lesions), 1 of 13 proximal and 2 of 10 distal tumours. Surgical complications after preoperative irradiation are distributed as follows: delayed wound healing 8, hematoma 2, thrombosis 2, skin infection 1, and abscess 1. On the other hand, complications appeared in 2 of 28 patients without preoperative irradiation: none in 9 patients having central tumours including 2 pelvic lesions, 1 in 12 patients with proximal tumours, and 1 in 7 patients with distal tumours. The multivariate regression test showed that the tumour site (central) is an influencing factor in the appearance of surgical complications. In central tumours, the surgical complication rate increases after preoperative irradiation; however, it is affected by the increase of the ratio of patients with pelvic tumours.

Adolescent↗
PubMed1997

[Psychosocial characteristics and attitudes of clients of day care centers and contact and counseling facilities].

Within the last 20 years, many day-care centers (Tagesstätten = TSn) and drop-in centers (Psychosoziale Kontakt- und Beratungsstellen = KBSn) have been set up in Germany. Although these institutions are widespread, there are hardly any empirical studies on the characteristics of their users or on their effects. In this study, 100 patients in TSn and KBSn in Berlin were examined. Social characteristics, psychopathology and attitudes of the patients were investigated. Almost all patients had been in psychiatric hospitals before. The current psychopathology varied greatly and was moderate on average. Two-thirds of the patients were pensioners, most of them living alone with just a few or no friends. Contact with other people and structured day activities were most often mentioned as positive aspects by the patients. The most frequent negative aspect was annoyance by fellow users. Patients in TSn were significantly younger and had higher scores on BPRS subscale anergia. In other variables, there was little difference between patients in the two institutions. The results suggest that both institutions--as intended--care for chronic mentally ill patients with poor social integration. For these patients they provide some compensations for a insufficient social network. Limitations and consequences of the findings are briefly discussed.

Adult↗
PubMed1997

Detection of the adrenal glands by endoscopic or transabdominal ultrasound.

BACKGROUND AND STUDY AIMS: The value of transabdominal and endoscopic ultrasound (EUS) in detecting normal adrenal glands is not yet established. The aim of our study was to evaluate whether these techniques can be routinely used to visualize the adrenal glands in patients without suspected adrenal pathology. PATIENTS AND METHODS: Transabdominal ultrasound was validated by examination of 10 corpses and was performed in 80 healthy volunteers (3.5 and 5 MHz). EUS of the left adrenal gland was performed in 154 consecutive patients referred for various other reasons. In 20 patients we attempted to visualize the right adrenal gland as well. RESULTS: Both adrenal glands were correctly identified in all of the 10 corpses once they were opened. In healthy volunteers, the right adrenal gland was visualized by transabdominal ultrasound in 79/80 patients (99 %) and the left adrenal gland in 55/80 patients (69 %). EUS allowed detection of the left adrenal gland in 151/154 patients (98%). In three patients EUS failed because of grossly distorted anatomy. In 6/20 patients we were also able to detect the right adrenal gland by EUS, which was obvious in two cases because of incidentalomas. CONCLUSION: Visualization of the right adrenal gland is almost always possible by transabdominal ultrasound, while its detection by EUS is successful only in some cases. The left gland is more difficult to detect by transabdominal ultrasound, while it can nearly always be seen using EUS. Therefore, a combined transabdominal and endoscopic ultrasonographic approach is useful for visualization of the adrenal glands and may enable diagnosis of even small adrenal masses.

Adrenal Glands↗
PubMed1997

Emergency room visits despite the availability of primary care: a study of high risk inner city infants.

Very low birth weight preterm infants randomized to receive comprehensive primary care in an ongoing clinical trial were prospectively evaluated to determine the cause of frequent emergency room use despite the availability of a primary healthcare provider and specific social services. Mothers were interviewed to assess knowledge of available resources, when to seek medical attention, and the perception of problems that limit access to health care. The healthcare provider was not called before 49% of the emergency room visits and mothers often did not recall what infant signs needed medical attention. Seventy-nine percent of emergency room visits were delayed more than 10 hours; and 15 of 62 (24%) emergency room visits resulted in admittance to the hospital. We conclude that in high-risk populations, the mere availability of primary care does not assure that it will be used. New strategies to help parents know when and how to use services are needed to increase the delivery of primary care.

Emergency Medical Services↗
PubMed1997

Ewing's sarcoma of the femur. Prognosis in 69 patients treated by the CESS group.

We reviewed the treatment outcome of 69 patients with Ewing's sarcoma of the femur. The patients received chemotherapy according to the CESS 81 (n 14), CESS 86 (n 43), and CESS 91P (n 12) protocols. The 10-year relapse-free survival rates were 36%, 65%, and 65% (p = 0.01). 68 patients received local treatment. The primary tumor was treated by surgery without radiotherapy in 28 patients; 1 developed a local recurrence and 7 metastases. 10 patients received radiotherapy alone; 4 developed metastases and 4 local recurrences and metastases. 30 cases had a combination of surgery and radiotherapy; 7 developed metastases and 1 a local recurrence and metastasis. The survival of patients after radiotherapy alone was worse than that of patients after surgery with/without radiotherapy (p = 0.005). Pathological fractures (n 16) did not influence the prognosis.

Adolescent↗
PubMed1997

A single and multiple dose bioavailability study with carbamazepine 400 mg retard tablets with reference to enzyme autoinduction and circadian time differences.

UNLABELLED: Both single and multiple dose bioequivalence studies are required to assess the quality of modified release formulations of drugs. In bioequivalence studies of drugs with enzyme autoinducing properties such as carbamazepine (CBZ), the standard multiple dose study design must be modified to guarantee equivalence of drug elimination. This problem was considered with regard to carbamazepine 400 retard AWD (test) whose bioavailability relative to a listed reference (Tegretal 400 retard) was studied in 2 randomized, open, crossover studies both with 18 healthy volunteers of Caucasian origin (20-36 years, 61.5-92 kg, 172-195 cm). The single dose study was done with 400 mg CBZ. Serum concentration time profiles of CBZ and its active metabolite CBZ-10,11-epoxide were determined until 144 h after administration. The multiple dose study was performed with 400 mg CBZ b.i.d. for 15 days (first 2 days: 200 mg b.i.d.) followed by a 7-day study with the alternative investigational product. 24-hour serum concentration time profiles of CBZ and its metabolite were measured on days 15 and 22 of the study. The quantitative drug analysis was done with an HPLC method the quality of which fulfilled the requirements of bioequivalence studies. Test was considered bioequivalent to reference with regard to the extent of absorption, if the 90% confidence intervals of the AUC0-infinity ratio (single dose) and AUC0-24h ratio (multiple dose) were within the range of 0.80-1.25, and with regard to rate of absorption if the 90% confidence intervals of the Cmax/AUC ratio (single dose) or AUCF0-24h ratio were within 0.70-1.43. The point estimators (90% confidence limits) of the AUC ratio (test/reference) of CBZ were 0.979 (0.94, 1.02) for the single and 1.01 (0.947, 1.076) for the multiple dose comparison. The point estimator (90% confidence limits) of the Cmax/AUC ratio was 0.989 (0.959, 1.020) and of the AUCF0-24h ratio 1.066 (0.937, 1.212). There were no circadian time differences in any pharmacokinetic parameter. IN CONCLUSION: Carbamazepine 400 retard AWD tablets were bioequivalent to reference with regard to extent and rate of absorption after both single and multiple dose administration.

Adult↗
PubMed1997

[Platelet count in the cat].

The technique of collecting blood samples is primarily responsible for the appearance of platelet-agglomeration in cats. Blood obtained by the conventional way ("one syringe technology", drips of blood) caused in 52% of the cases an activation of the large and therefore active thrombocytes however. Rejection of the first 2-5 ml blood for the platelet count ("two syringe technology") reduced the rate of platelet-agglomeration significantly. No big differences in platelet-agglomeration were found with regard to the place used for collecting blood (V. cephalica antebrachii/V. jugularis). Platelet-agglutination was observed with Li-Heparin, K-EDTA, Na-Citrat or ACD anticoagulated blood samples. Citrat (Na-Citrat, ACD) seemed to have a stabilizing effect on feline thrombocytes as has been described for human thrombocytes. The platelet count in cats should be performed within 30 minutes.

Animals↗