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K Witt

Publications and source records attributed to K Witt.

At least 37 records · Page 2Linked to original sources
PubMed2000

Toxaphenes and chlorinated naphthalenes in adipose tissue of children.

BACKGROUND: Chlorinated hydrocarbons are ingested by humans in food and accumulate in adipose tissue. At the University Kinderklinik, Mannheim, previously unknown substances have been found in children (e.g., the pesticide toxaphene and chlorinated naphthalenes). These substances have been widely used for industrial purposes in the past. Samples from West and East Germany; Saratov, Russia; and Almaty, Kazakhstan were examined to determine whether these substances are ubiquitous. METHODS: After Soxhlet extraction, the extracts were cleaned up using a liquid chromatographic technique. Measurement was performed by gas chromatography-mass spectrometry using negative chemical ionization in the single-ion-monitoring mode. RESULT: In specimens from all cities, toxaphene congeners Parlar 26 and Parlar 50 and six chlorinated naphthalenes were traced. Highest median load of toxaphene was 1.97 microg/kg for Parlar 26 and 2.36 microg/kg for Parlar 50 in Stralsund, East Germany. For chlorinated naphthalenes, the median was highest in Mannheim, West Germany, with 12.0 microg/kg. CONCLUSION: These findings show that monitoring these toxic substances remains necessary. Even though the use and as a consequence the amount of chlorinated hydrocarbons were reduced, these substances have by no means disappeared from the environment.

Adipose Tissue↗
PubMed2000

Declining autopsy rate in a French hospital: physician's attitudes to the autopsy and use of autopsy material in research publications.

CONTEXT: Autopsy rates have been declining throughout the world, although preservation of the autopsy is considered a fundamental principle of medical care. In France, the 1994 bioethics law requires physicians to inform relatives before performing an autopsy. OBJECTIVE: To analyze the following factors that potentially influence hospital autopsy rates: legal constraints, autopsy reporting times, opinions of physicians requesting autopsies and pathologists regarding the usefulness of autopsy in patient care, and use of autopsy material in research publications. DESIGN: Record of the annual numbers of deaths and autopsies during a 10-year period (1988-1997). Record of the delays for transmission of final autopsy report to the requesting physician. Questionnaire analyzing the possible factors influencing autopsy rate. Categorization of articles published by pathologists according to the use of autopsy material. SETTING: A 1000-bed, university teaching hospital in the Paris, France, area. PARTICIPANTS: Questionnaire addressed to physicians, head nurses, and mortuary staff. RESULTS: A total of 1454 autopsies were reviewed. The autopsy rate declined from 15.4% in 1988 to 3.7% in 1997. This decline was marked after 1994 and tended to be slower for neurologic indications than for other indications. The final report had not been communicated within 180 days in 620 (42.6%) of 1454 autopsies. Fifty-five of 105 respondents considered that the bioethics law was one cause of the recent decrease of autopsy rate. Considering the contribution of autopsy to medical research, 94 (81%) of 116 articles dealing with central nervous system but only 28 (6%) of 464 articles dealing with other organs used autopsy-derived material. CONCLUSIONS: The 1994 bioethics law seems to contribute to the decline of autopsy. Inadequate delays for communicating autopsy results are frequent. Except for neuropathologists, autopsy is a minor source of research material.

Attitude of Health Personnel↗
PubMed1999

Integrated approach to the multidimensional analysis of complex biological samples by microseparation techniques. Analysis of glycoprotein factor associated with cancer cachexia.

Microanalytical separation techniques including capillary liquid chromatography, capillary electrophoresis and capillary electrochromatography are suitable for detection of diagnostically important changes in the metabolic profiles of biological fluids. A prototype instrument was employed to serve as an integrated platform for the analysis of urine sample from patients suffering from cancer cachexia. The instrument provides for convenient, rapid and efficient multidimensional approach towards method development which would facilitate simultaneous analysis of complex biological mixtures by the above techniques.

Cachexia↗
PubMed1999

Efficacy of interferon treatment for patients with chronic hepatitis C: comparison of response in cirrhotics, fibrotics, or nonfibrotics.

Chronic hepatitis C patients (472 patients) were treated with consensus interferon (CIFN) or interferon (IFN) alfa-2b for 6 months in a large multicenter trial. Efficacy was assessed by clearance of hepatitis C virus (HCV) RNA using reverse transcription polymerase chain reaction (RT-PCR) (<100 copies/mL), normalization of serum alanine aminotransferase (ALT), and histological improvement. The purpose of these analyses was to compare these efficacy parameters in nonfibrotics, fibrotics, and cirrhotics. Patients with chronic HCV and cirrhosis showed the same benefit from IFN treatment as noncirrhotic patients when efficacy was assessed by clearance of serum HCV RNA or by histological benefit. Sustained HCV RNA response rates were similar when measured among nonfibrotic (11%), fibrotic (13%), and cirrhotic (11%) patients. Improvement in histologic activity index (HAI) scores was noted among all 3 groups. Cirrhotic patients had a lower sustained ALT response rate (12%) than did nonfibrotic patients (23%). Ninety percent of nonfibrotics, but only 71% of fibrotics and 67% of cirrhotics, who sustained a virological response normalized their ALT. This suggests that cirrhotic patients may clear the hepatitis C virus without normalization of ALT levels. The pattern of both HCV RNA clearance over time and ALT decrease was similar among nonfibrotics, fibrotics, and cirrhotics. Tolerability to IFN therapy was similar among the 3 groups except that more cirrhotics required dose reduction because of thrombocytopenia. In patients with cirrhosis, ALT levels may be a less appropriate endpoint in the measurement of response to therapy. We conclude that liver cirrhosis should not be a reason for excluding patients from therapy because both cirrhotic and fibrotic HCV patients benefit from IFN therapy not only by clearance of virus but by improvements in liver histology.

Adult↗
PubMed1999

M-cadherin and its sisters in development of striated muscle.

Cadherins are calcium-dependent, transmembrane intercellular adhesion proteins with morphoregulatory functions in the development and maintenance of tissues. In the development of striated muscle, the expression and function of mainly M-, N-, and R-cadherin has been studied so far. While these three cadherins are expressed in skeletal muscle cells, of these only N-cadherin is expressed in cardiac muscle. In this review, M-, N-, and R-cadherin are discussed as important players in the terminal differentiation and possibly also in the commitment of skeletal muscle cells. Furthermore, reports are described which evaluate the essential role of N-cadherin in the formation of heart tissue.

Animals↗
PubMed1999

Ten-year follow-up of silicone arthroplasty of the metacarpophalangeal joints in rheumatoid hands.

In resection arthroplasty of destroyed metacarpophalangeal joints stabilisation with a silicone spacer is regarded as the gold standard. In 28 patients with rheumatoid arthritis (34 hands) 102 arthroplasties of the metacarpophalangeal joint were assessed a median of 10 years postoperatively (range 8.7-12.5). All patients reported pronounced subjective relief of pain, and in three quarters function of the hand had improved. The median active range of movement decreased from 40 degrees (range 10 degrees-90 degrees) preoperatively to 35 degrees (range 5 degrees-85 degrees) postoperatively. Ulnar deviation was corrected from a median of 35 degrees (range 0 degrees-60 degrees) preoperatively to 10 degrees (range 0 degrees-40 degrees) postoperatively. The extension deficit was improved from a median of 35 degrees (range 10 degrees-80 degrees) before surgery to a median of 10 degrees (range 0 degrees-30 degrees) at follow up. Grip strength remained unchanged. Radiological examination showed surrounding osteolysis in 89% of the implants and 28% had broken. The well-known discrepancy between fair clinical and good subjective results with distinct radiological findings such as osteolysis was therefore confirmed. Material fatigue and sharp bony edges that result from osteolysis may be the cause of the relatively common implant fractures and ulnar deviation in this long-term follow-up.

Arthritis, Rheumatoid↗
PubMed1998

Re-treatment of chronic hepatitis C with consensus interferon .

A multicenter, open-label, phase 3 study was conducted in 337 patients with chronic hepatitis C virus (HCV) infection who had either not responded to previous interferon therapy or had relapsed after discontinuation of therapy with either consensus interferon (9 microg) or interferon alpha-2b (3 million U) three times a week for 24 weeks. Patients were randomized to receive a higher dose of consensus interferon (15 microg) administered subcutaneously three times a week for 24 or 48 weeks and then were observed for an additional 24 weeks. Patients who had relapsed after prior interferon therapy were more likely to have a sustained alanine aminotransferase response and HCV RNA response (as measured by reverse transcription-polymerase chain reaction with a sensitivity of < 100 copies/mL) than were patients who had not responded to prior interferon therapy. For relapsers, the sustained HCV RNA response rate was 58% (48 weeks) and 28% (24 weeks). The sustained alanine aminotransferase response for relapsers was 52% (48 weeks) and 39% (24 weeks). The sustained HCV RNA response rate among prior nonresponders was 13% (48 weeks) and 5% (24 weeks), and the sustained alanine aminotransferase response rate for nonresponders was 17% (48 weeks) and 12% (24 weeks). The administration of 15 microg of consensus interferon was well tolerated and was not associated with an increase in the incidence of side effects. These data demonstrate that re-treatment with 15 microg of consensus interferon is safe and effective therapy for patients with chronic hepatitis C who have either not responded to previous interferon therapy or relapsed after discontinuation of interferon therapy.

Adult↗
PubMed1997

[Therapy of rheumatoid destruction of the middle finger metacarpophalangeal joint with a Swanson silastic implant stabilized resection arthroplasty: comparative study of long and intermediate term results with and without implantation of titanium grommets].

Resection arthroplasty of the metacarpophangeal joints stabilized by a Swanson-Silastic-spacer is the golden standard in MP-joint destruction in R.A. 57 (Gr. I), 91 (Gr. II), and 102 (Gr. III) arthroplasties of the metacarpophalangeal joint were assessed in three groups of patients 3.5 years (Gr. I), 4.3 years (Gr. II), and 10.1 years (Gr. III), respectively, postoperatively on the average. In patients of group I titanium protectors, called grommets, were used additionally. Nearly all patients reported a marked relief of pain. Ulnar drift was corrected from an average of 22 degrees (Gr. I), 23 degrees (Gr. II), and 34 degrees (Gr. III) preoperatively. to 8 degrees (Gr. I), 7 degrees (Gr. II), and 12 degrees (Gr. III), respectively, postoperatively. Active range of motion remains unchanged with an average of 33 degrees (Gr. I), 38 degrees (Gr. II), and 42 degrees (Gr. III) ROM preoperatively and 42 degrees (Gr. I), 37 degrees (Gr. II), and 36 degrees (Gr. III) ROM, respectively, postoperatively. The average extension deficit had improved from 45 degrees (Gr. I), 32 degrees (Gr. II), and 33 degrees (Gr. III) at surgery to 18 degrees (Gr. I), 11 degrees (Gr. II), and 11 degrees (Gr. III), respectively, at the time of follow-up. Functional improvement of the hand was found in the medium term in 82% and in the longterm in 75% of the patients. The radiographical findings showed surrounding osteolysis in 45.7% (Gr. I), 63.5% (Gr. II), and 89.4% (Gr. III) of the implants and 0% (Gr. I), 16.5% (Gr. II), and 26.9% (Gr. III) broken spacers. From the medium to the longterm run there is an increase in radiographical deterioration. The additional use of titanium grommets in MP-joint arthroplasty seems to reduce reactive osteolysis and protects Swanson Silastic-spacers from breakage without substantial influence on the clinical outcome.

Arthritis, Rheumatoid↗
PubMed1996

[Status of the endoprosthesis in rheumatic metacarpophalangeal joints. Long-term results of metacarpophalangeal prostheses using Swanson's silastic spacers].

Advanced rheumatoid destruction of the metacarpophalangeal joints frequently requires implant arthroplasty. Among many different types of implants, the Swanson-Silastic-spacer is widely used. The long-term results of 102 arthroplasties of the metacarpophalangeal joint were assessed in 28 rheumatoid patients (34 hands) 10.1 years postoperatively on the average. Marked relief of pain was found in all patients. 75% of the patients reported functional improvement of the hand. Active range of motion decreased from 42 degrees preoperatively to 36 degrees postoperatively on the average. Ulnar drift was corrected from an average of 34 degrees preoperatively to 12 degrees postoperatively. The average extension deficit had improved from 33 degrees at surgery to 11 degrees at the time of follow-up. Grip strength remained unchanged. The radiographical findings showed surrounding osteolysis in 89.4% of the implants and 27.5% broken spacers. In comparison to other types of finger implants, Silastic-spacers showed similarly limited all over results, however, there seem to be less problems in salvage procedures.

Activities of Daily Living↗
PubMed1993

Automated suprathreshold screening for glaucoma: the Baltimore Eye Survey.

PURPOSE: To evaluate automated suprathreshold perimetric screening for glaucoma in a population-based survey of ocular disorders in east Baltimore, Maryland. METHODS: A population-based sample of persons > or = 40 years of age residing in 16 clusters was selected for an ocular screening examination that included automated suprathreshold testing with the Full Field 120 program of the Humphrey Field Analyzer. Subjects who failed the test underwent manual testing to confirm the defect. Subjects were referred for definitive examination by an ophthalmologist if they had an abnormal field, visual acuity worse than 20/30, intraocular pressure > 21 mm Hg, optic disc damage, a history of glaucoma, or shallow angles. The sensitivity and specificity of the automated visual field testing for identifying glaucoma was estimated and compared with other methods to screen for glaucoma. RESULTS: Of 5,341 subjects > or = 40 years of age who underwent a screening eye examination at neighborhood centers, 4,735 (89%) completed the automated field test. The median test time was 7.25 minutes per eye. Screening test results were abnormal in one or both eyes in 1,234 (26%) of the subjects. Kinetic perimetry was performed on 95% of these subjects, and defects were confirmed for 448 (36%) of them. Hence, 9.5% of the 4,735 subjects who completed the automated test were referred for definitive examination because the defect on automated perimetry was confirmed on manual testing. For a specificity of 90%, the sensitivity of the screening visual field test to detect glaucoma was 52% for 17 or more relative or absolute defects, higher than that of intraocular pressure at 39% for a cut-off of 20.5 mm Hg, vertical cup-to-disc ratio at 45% for a cut-off of 0.53, narrowest remaining rim width at 42% for a cut-off of 0.16, and was comparable to a combination of these and other nonfield parameters. CONCLUSION: Suprathreshold testing performed better than nonperimetry-based screening tests for glaucoma. However, a number of logistical weaknesses of this visual field screening method were identified.

Adult↗
PubMed1992

Resistive exercise training in cardiac patients. Recommendations.

Resistive exercise training has recently gained popularity in cardiopulmonary rehabilitation programmes. Improvement in muscular strength is important to facilitate return to daily vocational and recreational activities after a cardiac event. Resistive exercise has been shown to be haemodynamically safe for selected individuals with cardiovascular impairment, even at relatively high workloads. This form of training may enhance muscular strength and endurance, body composition, blood lipid and lipoprotein levels, and cardiovascular endurance, although further research is needed in cardiac populations. Patients should be clinically screened and perform a symptom-limited maximal graded exercise test prior to resistive training. Patients who have characteristics associated with an increased risk of cardiac event during exercise should avoid heavy resistive training. Free weights, cuff and hand weights, isotonic/isokinetic machines, elastics, and other resistive modalities may be used for exercise of major muscle groups in cardiopulmonary rehabilitation. Resistive training workloads may be determined by gradual acclimatisation or 1 repetition maximum testing. Heart rate, blood pressure, rate-pressure product and rating of perceived exertion should be determined during lifting movements. Circuit weight-training has been recommended and has been reported to improve strength, lean body mass, self-efficacy, and may decrease risk factors for coronary artery disease. Nonsustained isometric or combined dynamic/isometric exercises have also been recommended for cardiac patients since many vocations involve lifting/pushing movements or frequent isometric muscle contraction. There appears to be considerable benefit and minimal risk of resistive exercise training for patients with cardiovascular impairment. This mode of exercise may allow patients to perform daily strength tasks safely, more efficiently, and with greater self-confidence.

Adaptation, Physiological↗
PubMed1991

[Reduction of the use of hypnotics by health education. Results from a controlled intervention study in a local community].

The object of this investigation was to study the effect of a wide informative campaign on the sale of hypnotics in Holbaek. An informative health campaign was carried out via the media and the general practitioners for a period of 16 weeks. The campaign in the media consisted of a weekly article by the journalists in the local newspaper, a weekly advertisement in the daily and weekly newspapers, mention in the local radio daily and in the weekly medical programme and a leaflet about sleep handed out by the general practitioners. Twelve general practitioners elected to participate in the intervention programme: all patients who sought hypnotics had to come to an interview about the sleep problem. The control consisted of the remaining eight general practitioners in Holbaek. The sale of hypnotics was registered by the pharmacists during five weeks prior to, six weeks during and three and 15 months after the campaign. Five weeks before the campaign, the sale of hypnotics was 2.05 defined daily doses per patient (1.69 in the intervention group and 2.49 in the control group). During the last five weeks of the campaign, the sale had declined by 24% and by 29% in the follow up period. The decline commenced immediately in the intervention group but was only partly stable. After approximately eight weeks of the campaign, stable declines had occurred in both groups. Fifteen months later, the sale of hypnotics was approximately 39% lower than at the commencement of the campaign.

Denmark↗
PubMed1991

Ultrasound examination in jaundiced patients. Is computer-assisted preclassification helpful?

In this study we attempted to determine the diagnostic accuracy and reproducibility of ultrasonography (US) for jaundice and to see how US can best be combined with preliminary clinical-biochemical diagnoses to plan the invasive work-up. US proved reproducible in two diagnostic departments (127 agreements in 135 cases). But, since obstruction was underdiagnosed (15 double-false negatives), the predictive value of a negative result was only 0.83. By adding a term which represents the US conclusion, obstruction or not, to the Copenhagen pocket diagnostic chart score (based on the logistic model) we found that an obstructive conclusion increases the odds of obstruction by a factor of 25, and a non-obstructive conclusion decreases the odds by a factor of only 1.9. We conclude that the preliminary diagnosis is frequently sufficiently certain to be unalterable by US. This leaves only 40% of the jaundice cases in which US is necessary to plan invasive work-up. The US workload can even, it appears, be reduced to about 22% without appreciable penalty in terms of unrewarding invasive procedures. Using these strict indications, four US examinations seem to suffice to avoid one such error. Relying on either US or clinical-biochemical data alone is inferior to the combined strategy.

Algorithms↗
PubMed1991

Reliability of visual field results over repeated testing.

Fifty-one normal subjects, 337 with ocular hypertension, and 55 patients with glaucoma underwent C-30-2 testing on the Humphrey Field Analyzer on at least three occasions over a 6-year period. The time between tests was approximately 1 year. Using the manufacturer's standard for a reliable field (false-positive and false-negative rates, less than 33%; fixation losses, less than 20%), no trends in the proportion of reliable fields or the component indices were observed over time. Four percent of normal subjects, 9% of those with ocular hypertension, and 8% of patients with glaucoma were unable to meet the reliability standard every time they were tested. This repeated lack of reliability was due almost exclusively to fixation losses. However, patients with glaucoma were more likely to have repeatedly high false-negative responses than those with ocular hypertension or normal subjects, providing further evidence that false-negative responses are more indicative of glaucoma than of patient reliability.

Adult↗
PubMed1991

Dissemination of Pneumocystis carinii in patients with AIDS.

Extrapulmonary Pneumocystis carinii infections in AIDS are still rare although the number of cases is increasing. We present 2 cases of extrapulmonary pneumocystosis detected at our institution during an 8-month period. The first was a patient treated for P. carinii pneumonia (PCP) disseminated to liver, spleen and kidneys. The second patient had widely dissemination of P. carinii diagnosed at autopsy. Both patients had received aerosolised pentamidine (AP) for PCP prophylaxis. Totally we have treated patients with AP prophylaxis for 122 patient years and found a frequency of extrapulmonary spread of 1.6% compared to none in the 116 patient years on sulfamethoxazole-trimethoprim.

Acquired Immunodeficiency Syndrome↗
PubMed1990

Blindness and visual impairment in an American urban population. The Baltimore Eye Survey.

Data on the prevalence of blindness and visual impairment in multiracial urban populations of the United States are not readily available. The Baltimore Eye Survey was designed to address this lack of information and provide estimates of prevalence in age-race subgroups that had not been well studied in the past. A population-based sample of 5300 blacks and whites from east Baltimore, Md, received an ophthalmologic screening examination that included detailed visual acuity measurements. Blacks had, on average, a twofold excess prevalence of blindness and visual impairment than whites, irrespective of definition. Rates rose dramatically with age for all definitions of vision loss, but there was no difference in prevalence by sex. More than 50% of subjects improved their presenting vision after refractive correction, with 7.5% improving three or more lines. Rates in Baltimore are as high or higher than those reported from previous studies. National projections indicate that greater than 3 million persons are visually impaired, 890,000 of whom are bilaterally blind by US definitions.

Adult↗
PubMed1990

Increased incidence of developmental anomalies among descendants of carriers of methylenebisacrylamide-induced balanced reciprocal translocations.

N,N'-Methylenebisacrylamide (MBA), a dimer of the monomeric acrylamide, was studied for induction of clastogenic effects in germ cells of male mice. It was found to be effective in inducing dominant-lethal mutations and heritable translocations in maturing sperm. The semisterile translocation carriers and their normal counterparts were used to determine the health impact of transmitted chromosomal rearrangements through anatomical analysis of their immediate descendants in utero. As expected, semisterility resulted primarily from embryonic death during the periimplantation stages presumably caused by sperm segregants with unbalanced chromosome complement fertilizing some of the eggs. Among conceptuses that survived to mid- and late-gestation stages, there was an increased incidence of developmental anomalies including fetal death and phenotypic defects. These anomalies are assumed to be caused by certain types of unbalanced segregants that are compatible with survival beyond the periimplantation period. This class of unbalanced segregants represent in humans a major health problem to the mother and her conceptus.

Acrylamides↗