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Biomedical subjects

R Steffen

Publications and source records attributed to R Steffen.

At least 19 recordsLinked to original sources
PubMed2001

Five-year results from chemonucleolysis with chymopapain or collagenase: a prospective randomized study.

STUDY DESIGN: A 5-year clinical follow-up assessment of a prospective randomized study of chemonucleolysis using chymopapain (4000 IU) or collagenase (400 ABC units) was performed. SUMMARY OF BACKGROUND DATA: Intradiscal therapy can be performed for patients with contained discs by chemonucleolysis, percutaneous discectomy, or laser ablation. The oldest intradiscal therapy is chemonucleolysis with chymopapain. OBJECTIVE: The purpose of this study was to compare prospectively the efficacy of chymopapain and collagenase for intradiscal injection. METHODS: In this study, 100 patients with indication for intradiscal therapy were prospectively randomized to treatment with either chymopapain or collagenase. All the injections were performed by the double-needle technique with the patient under general anesthesia. The mean age of the patients was 35.5 years in the chymopapain group and 38 years in the collagenase group. An equal number of injections was performed at L4-L5 and L5-S1. RESULTS: After 5 years, good and excellent results were observed in 72% of the chymopapain group and 52% of the collagenase group when the surgically treated and lost patients were graded as poor. Using a scale of 0 (no pain) to 10 (intractable pain), the pain level dropped from 8.5 to 0.7 in the chymopapain group and from 8.6 to 0.9 in the collagenase group. Microdiscectomy at the injected level was required for 23 patients (14 in the collagenase group and 9 in the chymopapain group). CONCLUSIONS: After 5 years, no deterioration had occurred, as compared with the 1-year follow-up assessment. Chymopapain has proved to be safe, with one minor anaphylactic reaction, and effective even over the long term. Collagenase may need further study and cannot be recommended at this time.

Adult↗
PubMed2001

Enteroaggregative Escherichia coli as a major etiologic agent in traveler's diarrhea in 3 regions of the world.

Enteroaggregative Escherichia coli (EAEC) has been reported to cause traveler's diarrhea and persistent diarrhea in children in developing countries and in immunocompromised patients. To clarify the prevalence of EAEC in traveler's diarrhea, we studied 636 US, Canadian, or European travelers with diarrhea: 218 in Guadalajara, Mexico (June--August 1997 and 1998), 125 in Ocho Rios, Jamaica (September 1997--May 1998), and 293 in Goa, India (January 1997--April 1997 and October 1997--February 1998). Stool samples were tested for conventional enteropathogens. EAEC strains were identified by use of the HEp-2 assay. EAEC was isolated in 26% of cases of traveler's diarrhea (ranging from 19% in Goa to 33% in Guadalajara) and was second only to enterotoxigenic E. coli as the most common enteropathogen in all areas. Identification of EAEC reduced the number of cases for which the pathogen was unknown from 327 (51%) to 237 (37%) and explained 28% of cases with unknown etiology. EAEC was a major cause of traveler's diarrhea in 3 geographically distinct study areas.

Adult↗
PubMed2001

Time-resolved monitoring of flash-induced changes of fluorescence quantum yield and decay of delayed light emission in oxygen-evolving photosynthetic organisms.

The present contribution describes a new experimental setup that permits time-resolved monitoring of the rise kinetics of the relative fluorescence yield, Phi(rel)(t), and simultaneously of the decay of delayed light emission, L(t), induced by strong actinic laser flashes. The results obtained by excitation of dark-adapted samples with a train of eight flashes reveal (a) in suspensions of spinach thylakoids, Phi(rel)(t) exhibits a typical period four oscillation that is characteristic for a dependence on the redox states S(i)() of the water oxidizing complex (WOC), (b) the relative extent of the unresolved "instantaneous" rise to the level (100 ns) at 100 ns and the maximum values of Phi(rel)(t) attained at about 45 s after each actinic flash, (45 s) synchronously oscillate and exhibit the largest values at flash nos. 1 and 5 and minima after flash nos. 2 and 3, (c) opposite effects are observed for the normalized extent of the rise kinetics in the 100 ns to 5 s time domain of relative fluorescence yield, Phi(rel)(5 s) - Phi(rel)(100 ns), i.e., both parameters attain minimum and maximum values after the first/fifth and second/third flash, respectively, and (d) analogous features for the "fast" and "slow" ns-kinetics of the fluorescence rise were observed in suspensions of Chlamydomas reinhardtii cells. A slight phase shift by one flash is ascribed to physiological differences. The applicability of this noninvasive technique to study reactions of photosystem II, especially the reduction kinetics of P680(*)(+) and their dependence on the redox state S(i)() of the WOC, is discussed.

Animals↗
PubMed2001

Surgical or conservative treatment for chronic rotator cuff calcifying tendinitis--a matched-pair analysis of 100 patients.

Conservative or operative treatment for rotator cuff calcifying tendinitis was investigated in 100 patients in a matched-pair analysis. They were examined clinically and ultrasonographically 35-60 months after the initial visit. The mean Patte score was 91.8 for the patients who underwent surgical treatment and 81 for the ones who received conservative therapy (p < 0.004), while the age-related Constant-score was 103.4 and 95, respectively. Ultrasonography showed 28% calcifications in the surgical group, 18% newly formed and 10% that did not resolve after surgery. In the conservatively treated group, 33% calcifications were seen, of which 67% resolved. The number of rotator cuff ruptures was significantly higher in the conservative group. In the surgical group, 2% of partial tears and in the conservative group 5% of partial and 4% of complete cuff ruptures were found. Conservative treatment for calcifying tendinitis leads to less favourable pain results in the long term than surgical treatment. Surgery shortens the painful period and may reduce the number of future rotator cuff ruptures. Finally, the subjective functional outcome is significantly better after surgery.

Activities of Daily Living↗
PubMed2001

[Malaria--chemoprophylaxis 2001].

An estimated 20,000 to 30,000 cases of imported malaria are annually diagnosed in industrialised countries. Some 700 of them concern Swiss travellers and foreign guests. Exposure prophylaxis and chemoprophylaxis for high risk destinations lower the risk of malarial disease. The latter is defined as regular intake of antimalarial drugs in subtherapeutic dosage in order to suppress the development of clinical disease. Drugs are usually taken from one week before travel until four weeks after return from an endemic area. Mefloquine, doxycycline, chloroquine plus proguanil, and presumably soon also atovaquone plus proguanil are available in Switzerland for chemoprophylaxis.

Africa↗
PubMed2001

[Vaccinations for overseas travelers--new evidence and recommendations].

Vaccinations are an easy and highly effective way to keep travellers healthy. There are few problems with compliance, as all vaccinations are administered pretravel and many vaccines offer protection rates > 95% after a single dose (e.g. hepatitis A, yellow fever). Vaccination of hepatitis A and diphtheriatetanus are recommended for all developing countries. Polio is still indicated for Asia and Africa. Hepatitis B, if possible in combination with A, is recommended for persons travelling for > 30 days, travellers < 35 years, and for people showing special risk behaviour (e.g. high-risk sports, unprotected sexual intercourse). Depending on destination and kind and duration of travel, further vaccinations have to be considered, e.g.: yellow fever (endemic areas, rule of entry), rabies (trekking, travel in remote areas), typhoid fever (Indian sub-continent), meningococcal meningitis (meningitis belt, pilgrims to Saudi-Arabia), tick-borne encephalitis (endemic areas in Europe and Asia), influenza (persons at special risk of complications), Japanese encephalitis (low standard travel in rural areas of Southeast Asia > 30 days), measles (particularly endemic in Africa). Cholera vaccination is virtually never indicated. Several vaccines can be delivered at the same time.

Cholera Vaccines↗
PubMed2001

Guidelines for adults on self-medication for the treatment of acute diarrhoea.

Acute uncomplicated diarrhoea is commonly treated by self-medication. Guidelines for treatment exist, but are inconsistent, sometimes contradictory, and often owe more to dogma than evidence. An ad hoc multidisciplinary group has reviewed the literature to determine best practice. In general it is recognized that treatment of acute episodes relieves discomfort and social dysfunction. There is no evidence that it prolongs the illness. Self-medication in otherwise healthy adults is safe. Oral loperamide is the treatment of choice. Older anti-diarrhoeal drugs are also effective in the relief of symptoms but carry the risk of unwanted adverse effects. Oral rehydration solutions do not relieve diarrhoea, and confer no added benefit for adults who can maintain their fluid intake. Probiotic agents are, at present, limited in efficacy and availability. Antimicrobial drugs, available without prescription in some countries, are not generally appropriate for self-medication, except for travellers on the basis of medical advice prior to departure. Medical intervention is recommended for the management of acute diarrhoea in the frail, the elderly (> 75 years), persons with concurrent chronic disease, and children. Medical intervention is also required when there is no abatement of the symptoms after 48 h, or when there is evidence of deterioration such as dehydration, abdominal distension, or the onset of dysentery (pyrexia > 38.5 degrees C and/or bloody stools).

Acute Disease↗
PubMed2001

Conservative management of intragastric migration of Swedish adjustable gastric band by endoscopic retrieval.

BACKGROUND: Intragastric migration is a known complication of gastric banding for morbid obesity. METHODS: Instead of immediate reoperation, complete migration of the Swedish Adjustable Gastric Band (SAGB) into the gastric lumen was awaited in 4 patients who were asymptomatic. RESULTS: After completed migration, the episternally placed access port was removed with the patient under local anesthesia, and the disconnected adjustable band was retrieved endoscopically. All 4 patients underwent rebanding with SAGB within 3 months after extraction. CONCLUSIONS: With this procedure, patients who are asymptomatic can be spared laparotomy and possibly gastrostomy.

Adult↗
PubMed2001

In vitro antimicrobial susceptibility testing of bacterial enteropathogens causing traveler's diarrhea in four geographic regions.

The emergence of resistant enteropathogens has been reported worldwide. Few data are available on the contemporary in vitro activities of commonly used antimicrobial agents against enteropathogens causing traveler's diarrhea (TD). The susceptibility patterns of antimicrobial agents currently available or under evaluation against pathogens causing TD in four different areas of the world were evaluated. Pathogens were identified in stool samples from U.S., Canadian, or European adults (18 years of age or older) with TD during 1997, visiting India, Mexico, Jamaica, or Kenya. MICs of 11different antimicrobials were determined against 284 bacterial enteropathogens by the agar dilution method. Ciprofloxacin, levofloxacin, ceftriaxone, and azithromycin were highly active in vitro against the enteropathogens, while traditional antimicrobials such as ampicillin, trimethoprim, and trimethoprim/sulfamethoxazole showed high levels and high frequencies of resistance. Rifaximin, a promising and poorly absorbable drug, had an MIC at which 90% of the strains tested were inhibited of 32 microg/ml, 250 times lower than the concentration of this drug in the stools. Amdinocillin, nalidixic acid, and doxycycline showed moderate activity. Fluoroquinolones are still the drugs of choice for TD in most regions of the world, although our study has a limitation due to the lack of Escherichia coli samples from Kenya and possible bias in selection of the patients for evaluation. Azithromycin and rifaximin should be considered as promising new agents. The widespread in vitro resistance of the traditional antimicrobial agents reported since the 1980s and the new finding of resistance to fluoroquinolones in Southeast Asia are the main reasons for monitoring carefully the antimicrobial susceptibility patterns worldwide and for developing and evaluating new antimicrobial agents for the treatment of TD.

Anti-Bacterial Agents↗
PubMed2001

Suppression of allograft rejection in the sponge Suberites domuncula by FK506 and expression of genes encoding FK506-binding proteins in allografts.

Porifera (sponges) are, evolutionarily, the oldest metazoan phylum. Recent molecular data suggest that these animals possess molecules similar to and homologous with those of the innate and adaptive immune systems of higher Metazoa. Applying the biological system of parabiosis and the technique of differential display of mRNA, two cDNAs encoding putative FK506-binding proteins were isolated. FK506 is successfully used in clinics as a drug to prevent allograft rejection and is toxic to Suberites domuncula cells in vitro at doses above 100ng ml(-1). Autograft fusion of transplants from S. domuncula was not affected by FK506. Allograft non-fusion was not affected by FK506 at toxic doses; however, at the non-toxic dose of 20ng ml(-1), the allografts fused with each other. It is shown that at the attachment zone in untreated and (particularly drastic) in FK506-treated allografts, expression of the genes encoding the FK506-binding proteins is upregulated. These data indicate that the drug FK506 suppresses allograft rejection in S. domuncula, most probably via interaction with expression of the gene coding for the FK506-binding proteins.

Amino Acid Sequence↗
PubMed2001

Effectiveness and tolerability of melatonin and zolpidem for the alleviation of jet lag.

BACKGROUND: The aim of this study was to compare the effectiveness and tolerability of a chronobiotic (melatonin) with a hypnotic (zolpidem) and the combination of both substances to alleviate jet lag symptoms associated with eastward travel. METHODS: This double-blind, randomized, placebo-controlled study is based on 137 volunteers flying from Switzerland to the American continent and back (6-9 time zones). The participants either received melatonin 5 mg (n = 35), zolpidem 10 mg (n = 34), a combination thereof (n = 29) or placebo (n = 39) on the eastbound flight back to Switzerland and once daily at bedtime on 4 consecutive days after the flight. The test battery included daily sleep logs, symptoms questionnaires, and the Profile of Mood States (POMS). Also, on the last treatment day, Visual Analog Scales (VAS) were completed to assess overall jet lag ratings and treatment effectiveness. Baseline data were collected on 4 consecutive days 2 wk after the flight. During post-flight treatment and baseline, motor activity was assessed in a subgroup of 49 subjects using wrist-worn ambulatory monitors. RESULTS: The self-rated sleep quality was significantly improved by zolpidem, especially during the night flight. Subjects taking zolpidem reported significantly less jet lag and zolpidem was rated as the most effective jet lag medication. However, zolpidem and the combination melatonin/zolpidem were less well tolerated than melatonin alone; adverse event reports included nausea, vomiting, amnesia and somnambulia to the point of incapacitation. Confusion, morning sleepiness and nausea were highest in the combination group. CONCLUSIONS: All active treatments led to a decrease of jet lag severity with zolpidem being the most effective treatment, particularly in facilitating sleep on night flights. Potential individual adverse reactions to this hypnotic have to be considered.

Adolescent↗
PubMed2000

Risk and aetiology of diarrhoea at various tourist destinations.

Almost two of three tourists developed traveller's diarrhoea during 2-week stays at high-risk destinations. Large differences in infection rates between hotels were seen. Patients with milder forms of diarrhoea show a similar chronology to those more severely affected. Although enterotoxigenic Escherichia coil was the most frequent cause, viral pathogens were detected more often than in other studies.

Brazil↗
PubMed2000

Delayed fluorescence emitted from light harvesting complex II and photosystem II of higher plants in the 100 ns-5 micros time domain.

This study presents the first report on delayed fluorescence (DF) emitted from spinach thylakoids, D1/D2/Cytb-559 preparations and solubilized light harvesting complex II (LHCII) in the ns time domain after excitation with saturating laser flashes. The use of a new commercially available multichannel plate with rapid gating permitted a sufficient suppression of detector distortions due to the strong prompt fluorescence. The following results were obtained: (a) in dark-adapted thylakoids, the DF amplitudes at 100 ns and 5 micros after each flash of a train of saturating actinic pulses exhibit characteristic period four oscillations of opposite sign: the DF amplitudes at 100 ns oscillate in the same manner as the quantum yield of prompt fluorescence, whereas those at 5 micros resemble the oscillation of the micros kinetics of P680(.) reduction in samples with an intact water oxidizing complex, (b) the quantum yield of total DF emission in the range up to a few micros is estimated to be <10(-4) for thylakoids, (c) the DF of D1/D2/Cytb-559 exhibits a monophasic decay with tau approximately 50 ns, (d) DF emission is also observed in isolated LHCII with biphasic decay kinetics characterized by tau values of 65 ns and about 800 ns, (e) in contrast to thylakoids, the amplitudes of DF in D1/D2/Cytb-559 preparations and solubilized LHCII do not exhibit any oscillation pattern and (f) all spectra of DF from the different sample types are characteristic for emission from the lowest excited singlet state of chlorophyll a. The implications of these findings and problems to be addressed in future research are briefly discussed.

Fluorescence↗
PubMed2000

Bilateral Madelung's deformity without signs of dyschondrosteosis within five generations in a European family--case report and review of the literature.

The paper presents a European family showing bilateral Madelung's deformity within five consecutive generations. Females as well as males are affected alternately indicating autosomal dominant inheritance. Despite of a body height within the lower normal range in two patients the diagnosis of dyschondrosteosis could not be clearly established as further hints for dwarfism are missing. The etiology of Madelung's deformity may be difficult to establish. There seems to be the possibility of an inheritance independent from the complete syndroma of dyschondrosteosis. Therefore the genetic counselling will always be difficult and has to regard the wide variety of symptoms ranging from little pain and cosmetic disturbance to moderate pain and functional impairment.

Bone Diseases, Developmental↗
PubMed2000

Local anaesthetic injection with and without corticosteroids for subacromial impingement syndrome.

Fifty patients with impingement syndrome refractory to long-term conservative treatment were randomized to three treatment groups. All patients received an injection of 10 ml 0.5% bupivacaine, in group 1 without corticosteroid, in group 2 with crystalline corticosteroid and in group 3 with lipoid corticosteroid. Treatment in group 1 had to be stopped because of inefficacy. In groups 2 and 3 favorable results were achieved in 19 out of 40 patients.

Adult↗