Comparison of nasal immunohistology in patients with seasonal rhinoconjunctivitis treated with topical steroids or specific allergen immunotherapy

BACKGROUND

Specific allergen immunotherapy (SIT) and nasal steroids (NS) are considered effective anti-inflammatory treatments for allergic rhinitis, although their mechanism of action differs.

OBJECTIVE

The aim of this study was to examine the effect of treatment with NS and SIT on different populations of inflammatory cells in the nasal mucosa and to compare cell numbers before and during the birch pollen season in patients with seasonal allergic rhinitis.

METHODS

In a randomized, double-blind, double dummy comparative study, 41 patients with seasonal rhinoconjunctivitis were treated with birch SIT or NS (budesonide 400 microg daily). Treatment with NS started before the birch pollen season and at the same time SIT-treated patients reached the maintenance dose. Nasal biopsies for immunohistochemistry were obtained before the season and start of the treatments and at the peak of the pollen season during treatment.

RESULTS

Symptoms of rhinoconjunctivitis increased significantly in both groups during the pollen season but less in the NS-treated group and the difference between the treatment groups was significant at the end of the season (P = 0.03). Immunohistochemistry of nasal biopsies from NS-treated patients showed significantly fewer CD1a+, IgE+ and Fc epsilonRI+ cells during the season compared with preseason (P = 0.02, P = 0.001 and P = 0.0004, respectively) and with seasonal values of the SIT-treated group (P = 0.002, P = 0.002 and P = 0.0004 respectively).

CONCLUSION

Treatment with NS but not SIT decreased the numbers of CD1a+, IgE+ and Fc epsilonRI+ cells during the birch pollen season. Our data indicate that treatment with NS has a broader anti-inflammatory range than SIT.

Doppel-induced cerebellar degeneration in transgenic mice

Doppel (Dpl) is a paralog of the mammalian prion protein (PrP); it is abundant in testes but expressed at low levels in the adult central nervous system. In two Prnp-deficient (Prnp(0/0)) mouse lines (Ngsk and Rcm0), Dpl overexpression correlated with ataxia and death of cerebellar neurons. To determine whether Dpl overexpression, rather than the dysregulation of genes neighboring the Prn gene complex, was responsible for the ataxic syndrome, we placed the mouse Dpl coding sequence under the control of the Prnp promoter and produced transgenic (Tg) mice on the Prnp(0/0)-ZrchI background (hereafter referred to as ZrchI). ZrchI mice exhibit neither Dpl overexpression nor cerebellar degeneration. In contrast, Tg(Dpl)ZrchI mice showed cerebellar granule and Purkinje cell loss; the age of onset of ataxia was inversely proportional to the levels of Dpl protein. Crosses of Tg mice overexpressing wild-type PrP with two lines of Tg(Dpl)ZrchI mice resulted in a phenotypic rescue of the ataxic syndrome, while Dpl overexpression was unchanged. Restoration of PrP expression also rendered the Tg(Dpl) mice susceptible to prion infection, with incubation times indistinguishable from non-Tg controls. Whereas the rescue of Dpl-induced neurotoxicity by coexpression of PrP argues for an interaction between the PrP and Dpl proteins in vivo, the unaltered incubation times in Tg mice overexpressing Dpl in the central nervous system suggest that Dpl is unlikely to be involved in prion formation.

A double-blinded, comparative study of the effects of short preseason specific immunotherapy and topical steroids in patients with allergic rhinoconjunctivitis and asthma

BACKGROUND

Both specific immunotherapy (SIT) and nasal steroid (NS) have been shown to effectively reduce symptoms of allergic rhinitis. Although a number of investigators have convincingly shown anti-inflammatory effects of both treatments in separate studies, few comparative studies have been performed.

OBJECTIVE

The purpose of this study was to compare the effects of preseason SIT with a standardized allergen extract and NS in seasonal allergic disease (rhinoconjunctivitis and asthma).

METHODS

We examined 41 patients allergic to birch pollen, 21 with rhinoconjunctivitis and 20 with both rhinoconjunctivitis and asthma; they were treated in a randomized, double-blinded comparative study with birch SIT and NS (budesonide 400 microg daily). Bronchial hyperresponsiveness was measured before and during the season. Changes in eosinophil number, eosinophil cationic protein, and eosinophil chemotactic activity (ECA) in peripheral blood were investigated.

RESULTS

Symptoms of rhinoconjunctivitis increased significantly less in the NS-treated patients than in the SIT-treated patients during the final 2 weeks of the season (P = .03 and P = .04, respectively). Seasonal peak expiratory flow values decreased significantly only in the NS-treated patients (P = .01). In the NS-treated patients, bronchial hyperresponsiveness increased significantly during the season (P = .0001); however, SIT treatment prevented seasonal PC(20) increase in the asthmatic patients. Measurement of blood eosinophils, eosinophil cationic protein, and eosinophil chemotactic activity demonstrated significant seasonal increase only in the NS-treated asthmatic patients.

CONCLUSION

Treatment with NS was more effective than short-course preseason SIT in reducing symptoms of rhinoconjunctivitis; however, the 2 therapies were equivalent in terms of the need for rescue medication. SIT prevented seasonal increase in bronchial hyperresponsiveness, eosinophil number, eosinophil cationic protein, and eosinophil chemotactic activity only in asthmatic patients. The mechanisms underlying bronchial hyperresponsiveness developing during allergen exposure in rhinitis might be different from those operating in asthma.

[Prevention of congenital malformations by means of folic acid - insurmountable problems due to the German penal code and German drug legislation when preparing a preconceptional model in Saxony-Anhalt]

For the last 20 years the prophylactic effect of the vitamin folic acid against the occurrence of neural tube defects has been known but in Germany this fact has not been realized by the public. The recommendations by medical institutions fail, among other reasons, because a folic acid prescription by gynaecologists comes too late in the course of events, i.e., women go to the gynaecologist when pregnancy has already set in and it is too late for preventive measures. An effective folic acid prophylaxis must take place before the onset of pregnancy. Data from the regional surveillance of congenital anomalies of the German Federal State of Saxony-Anhalt and interviews with women in maternity, as well as gynaecologists, indicate that there is a substantial knowledge deficit concerning folic acid prophylaxis. In 1998, therefore, a working group was set up in Saxony-Anhalt. It comprises representatives from interested institutions and has the goal of rectifying the knowledge deficit of women of childbearing age by way of a broad-based campaign while making use of the results of regional congenital anomalies monitoring. A pharmaceutical company was enlisted for cost-free distribution of its folic acid product. Legal problems with the prescription drug laws, the law against unfair competitive practices, the advertising of medicaments law and the SGB V (social code) made it impossible to procure multivitamins containing folic acid free of charge for women wanting a child. A highly differentiated legislation has hitherto prevented an elementary improvement in prevention.

Pyogranulomatous blepharitis in two dogs

Two cases of pyogranulomatous blepharitis (inflammation of the lid margins) in the dalmatian are described. The diagnosis was confirmed on biopsy of the lid lesions. Bacteriology performed in one case was negative. Both cases responded to treatment: one responded well to a course of systemic steroids (prednisolone 1 mg/kg at a decreasing dose over three weeks), while the other, which was negative on culture, responded to a six-week course of cephalexin (30 mg/kg twice daily). This second dog also presented with a localised lymphadenopathy; the owner had suffered a similar reaction three years previously as a result of a penetrating injury by a pyracantha thorn.

Psychometrische Schweregradbeurteilung bei dementiellen Erkrankungen: Ein Vergleich von MMST, ADAS, BCRS und SKT

Zusammenfassung: In einer multizentrischen Studie wurden mit MMST, ADAS, BCRS und SKT vier im Bereich der dementiellen Alterserkrankungen international eingesetzte Testverfahren miteinander verglichen. Es wurde überprüft, inwieweit die Verfahren zwischen Patientengruppen mit klinisch unterschiedlich schwer beurteilten kognitiven Einbußen differenzieren können, ob die mit den einzelnen Tests getroffenen Störungsgradzuordnungen übereinstimmen und welche Entsprechungen zwischen den Testscores bestehen. Weiterhin wurde die faktorielle Struktur der Testbatterie analysiert. Die Ergebnisse legen eine unterschiedliche Störungsgradsensitivität von MMST, ADAS, BCRS und SKT in verschiedenen Stadien der Demenz nahe. Die auf der Grundlage der vier Tests vorgenommenen Schweregradbeurteilungen des dementiellen Syndroms weichen voneinander ab. In einer Regressionsanalyse konnten dafür in erster Linie die zwischen den verschiedenen Testverfahren bestehenden Unterschiede in der Definition von Schweregraden kognitiver Beeinträchtigungen verantwortlich gemacht werden. Die Faktorenanalyse erbrachte eine Lösung, die die Kernsymptomatik der Demenz abbildet und damit auf die faktorielle Validität der eingesetzten Tests hinweist.

Ataxia in prion protein (PrP)-deficient mice is associated with upregulation of the novel PrP-like protein doppel

The novel locus Prnd is 16 kb downstream of the mouse prion protein (PrP) gene Prnp and encodes a 179 residue PrP-like protein designated doppel (Dpl). Prnd generates major transcripts of 1.7 and 2.7 kb as well as some unusual chimeric transcripts generated by intergenic splicing with Prnp. Like PrP, Dpl mRNA is expressed during embryogenesis but, in contrast to PrP, it is expressed minimally in the CNS. Unexpectedly, Dpl is upregulated in the CNS of two PrP-deficient (Prnp(0/0)) lines of mice, both of which develop late-onset ataxia, suggesting that Dpl may provoke neurodegeneration. Dpl is the first PrP-like protein to be described in mammals, and since Dpl seems to cause neurodegeneration similar to PrP, the linked expression of the Prnp and Prnd genes may play a previously unrecognized role in the pathogenesis of prion diseases or other illnesses.

Prion protein of 106 residues creates an artifical transmission barrier for prion replication in transgenic mice

A redacted prion protein (PrP) of 106 amino acids with two large deletions was expressed in transgenic (Tg) mice deficient for wild-type (wt) PrP (Prnp0/0) and supported prion propagation. RML prions containing full-length PrP(Sc)produced disease in Tg(PrP106)Prnp0/0 mice after approximately 300 days, while transmission of RML106 prions containing PrP(Sc)106 created disease in Tg(PrP106) Prnp0/0 mice after only approximately 66 days on repeated passage. This artificial transmission barrier for the passage of RML prions was diminished by the coexpression of wt MoPrPc in Tg(PrP106)Prnp+/0 mice that developed scrapie in approximately 165 days, suggesting that wt MoPrP acts in trans to accelerate replication of RML106 prions. Purified PrP(Sc)106 was protease resistant, formed filaments, and was insoluble in nondenaturing detergents. The unique features of RML106 prions offer insights into the mechanism of prion replication, and the small size of PrP(Sc)106 should facilitate structural analysis.

Doxycycline control of prion protein transgene expression modulates prion disease in mice

Conversion of the cellular prion protein (PrPC) into the pathogenic isoform (PrPSc) is the fundamental event underlying transmission and pathogenesis of prion diseases. To control the expression of PrPC in transgenic (Tg) mice, we used a tetracycline controlled transactivator (tTA) driven by the PrP gene control elements and a tTA-responsive promoter linked to a PrP gene [Gossen, M. and Bujard, H. (1992) Proc. Natl. Acad. Sci. USA 89, 5547-5551]. Adult Tg mice showed no deleterious effects upon repression of PrPC expression (>90%) by oral doxycycline, but the mice developed progressive ataxia at approximately 50 days after inoculation with prions unless maintained on doxycycline. Although Tg mice on doxycycline accumulated low levels of PrPSc, they showed no neurologic dysfunction, indicating that low levels of PrPSc can be tolerated. Use of the tTA system to control PrP expression allowed production of Tg mice with high levels of PrP that otherwise cause many embryonic and neonatal deaths. Measurement of PrPSc clearance in Tg mice should be possible, facilitating the development of pharmacotherapeutics.

Activation of B-lymphocytes during pollen season. Effect of immunotherapy

BACKGROUND

B-lymphocytes play an important part in the allergic reaction as producers of IgE antibodies.

OBJECTIVE

To investigate the cell surface expression of the activation antigens CD23, CD40 and HLA-DR on B-lymphocytes in birch pollen allergic patients before and during birch pollen season and to study the effect of immunotherapy.

METHODS

The study included 24 birch pollen allergic patients half of whom were treated with immunotherapy against birch pollen before the start of the season. Eleven of the 24 patients had asthma. Blood samples were taken and lung function was registered before the season began and before the immunotherapy treatment in January to February and during the season in May. The relative number of B-lymphocytes (CD19+) of the lymphocyte population and the cell surface expression of CD23, CD40 and HLA-DR on B-lymphocytes was measured by the use of flow cytometry.

RESULTS

In the control group of patients the relative number and concentration of B-lymphocytes, the cell surface expression of CD23, CD40 and HLA-DR on B cells, and the serum concentration of IgE increased during season compared with before season. In contrast, in the immunotherapy treated patients no changes in the number of B cells or cell surface expression of CD23, CD40 and HLA-DR were demonstrated.

CONCLUSION

The elevated expression of CD23, CD40 and HLA-DR on B cells, combined with increased levels of IgE in allergic patients during season could be explained by the effect of cytokines produced by activated TH2 cells. A shift from TH2 to TH1 cells might be the mechanism after the absence of signs of B-cell activation in immunotherapy treated patients. The prevention of increased cell surface expression on B cells by immunotherapy may constitute a significant mechanism behind the beneficial effects of immunotherapy in the treatment of pollen atopy.

Transurethral resection of the prostate with microprocessor controlled electrosurgical unit

PURPOSE

We analyzed the efficacy and side effects of a microprocessor controlled high frequency unit for transurethral resection of the prostate.

MATERIALS AND METHODS

A high frequency device with microprocessor control was used in 934 consecutive patients undergoing transurethral resection of the prostate. Indications for transurethral resection, medical history, preoperative findings, operative parameters, operative and immediate postoperative complications, and postoperative peak flow rate and residual urine were evaluated.

RESULTS

Postoperative peak flow rate and residual urine were comparable to those with standard transurethral resection of the prostate. One patient died on postoperative day 1 for a mortality rate of 0.1%. The immediate morbidity rate was 6.9%.

CONCLUSIONS

Morbidity and mortality in this study were lower than those in previous series on transurethral resection of the prostate.

[Interscalene brachial plexus catheter for anesthesia and postoperative pain therapy. Experience with a modified technique]

OBJECTIVES

This study was conducted to evaluate a modified technique of interskalene brachial plexus anaesthesia (ISB) and postoperative catheter analgesia for shoulder surgery. The original method described by Winnie bears some rare but life-threatening complications (inadvertent subarachnoid or intra-arterial injection, pneumothorax).

MATERIALS AND METHODS

Ninety-one patients with chronic rheumatoid arthritis who were scheduled for open or closed shoulder surgery received a modified ISB with catheter insertion. The injection site was more cephalad than that described by Winnie and the cannula was directed towards the junction between the medial and lateral third of the clavicle. Intra- and postoperative management, complications, and patients' satisfaction were recorded and evaluated.

RESULTS

Implementation of ISB was possible in all cases, however, 3% of these presented technical problems. Anaesthesia with 300 mg mepivacaine 1% was successful in 94% of patients without and in 96% with augmentation after an average of 32 min; 10% of the patients suffered a drop in blood pressure after being placed in the beach-chair position for surgery. Postoperatively, all patients received 20 ml bupivacaine 0.25% for pain management via the catheter; 11% needed an additional analgesic drug. The catheter was removed after an average of 5 days. Signs of superficial local infection were noticed in 8 cases. Side effects occurred in 13% as Horner's syndrome, in 6.5% as recurrent laryngeal nerve block, and in 3.3% as phrenic nerve block. The acceptance of this anaesthetic technique among the patients was very high (96.7%).

CONCLUSION

We consider the modified ISB with catheter a safe and effective procedure for anaesthesia and postoperative pain management of open and closed shoulder surgery.

Evidence of the cross-cultural stability of the factor structure of the SKT short test for assessing deficits of memory and attention

Many of the psychometric instruments employed in dementia research are adapted versions of tests developed in countries different from those in which they are applied. The validity of these instruments has been established in their countries of origin; however, there is little information available regarding their validity when transferred to other cultures. The SKT, a short cognitive performance test for the assessment of memory and attention deficits developed and validated in Germany, was administered in research centers in Chile, Greece, Russia, and England. SKT raw scores were factor analyzed with regard to a prespecified target structure, i.e., the factor solution found for a large German reference sample. The cross-cultural stability of the test was assessed using a statistical method that combined the perfect congruent weights approach and the bootstrapping technique. This procedure allowed for testing the similarity between factorial solutions obtained for the different centers. Results clearly indicate the factorial stability of the SKT in the countries participating in the study.

Priming of eosinophil adhesion in patients with birch pollen allergy during pollen season: effect of immunotherapy

The adhesion of eosinophil granulocytes to E-selectin, vascular cell adhesion molecule-1 (VCAM-1), and intercellular adhesion molecule-1 (ICAM-1) was investigated before and during birch pollen season in 24 patients allergic to birch pollen who had rhinoconjunctivitis and, in half of the cases, asthma during season. Half of the patients were undergoing specific immunotherapy for birch pollen allergy. Increased adhesion to VCAM-1 and ICAM-1 (p < 0.05) during season as compared with before season was demonstrated by eosinophils of patients in the control group and by eosinophils of the patients without asthma treated with immunotherapy, but not by eosinophils from the immunotherapy-treated patients with asthma. Eosinophils from the control group of patients demonstrated increased cell surface expression of CD18 and CD49d (p < 0.05 and p < 0.01, respectively) during season as compared with before season, and eosinophils from the immunotherapy-treated patients showed increased cell surface expression of CD49d (p < 0.01) during season. Simultaneous measurement of neutrophil adhesion revealed increased adhesion to E-selectin and ICAM-1 (p < 0.01) during season compared with before season in the immunotherapy-treated group of patients. Neutrophils from the control subjects without asthma showed increased adhesion to E-selectin (p < 0.05) during season. In conclusion, eosinophils from patients allergic to birch pollen demonstrated priming of the adhesion to VCAM-1 to ICAM-1 during birch pollen season. Immunotherapy treatment prevented the priming of eosinophil adhesion during pollen season in the patients allergic to birch pollen who had asthma, but not in those without asthma. In contrast, neutrophils from the immunotherapy-treated patients, both with and without asthma, demonstrated priming of the adhesion to E-selectin and ICAM-1 during season. The latter results indicate that immunotherapy, in case of the patients allergic to birch pollen with asthma induced a shift from the production of primarily eosinophil priming agents to primarily neutrophil priming agents, which may be caused by a shift from Th2 to Th1 lymphocytes.

[Paralytic myoglobinuria in greyhounds]

In five Greyhounds the provisional diagnosis of paralytic myoglobinuria was confirmed by means of serum enzyme examination and urine analysis. The importance of creatine kinase examination is emphasized. The worsening of the condition was prevented by prompt therapy with massive water and electrolyte infusion of the affected dogs. Recovery was achieved in all cases.

Multiple pathways of reversion in viroids for conservation of structural elements

From site-directed mutagenesis of potato spindle tuber viroid (PSTVd) it had been concluded earlier that the formation of a thermodynamically metastable structure containing hairpin II (HP II) is critical for infectivity. In order to differentiate between structural and sequence effects, in the present work base pairs in HP II were exchanged by site-directed double mutations without significant alterations in the native rod-like structure of PSTVd. The mutants were viable and genetically stable in the first generation, but one of the two mutations reverted to the wild-type nucleotide in the second generation. Single-site mutations in the stem of HP II, which had been described as revertants to the wild-type sequence earlier, were analysed with respect to the time course of reversion and the sequence variation during reversion. All replicating sequence variants were separated by gel electrophoretic techniques and the sequences and their relative frequencies were determined. From both types of studies it can be concluded (i) that HP II is a functional element in the (-)strand replication intermediate, generated due to sequential folding during synthesis, and that it is essential for template activity of (+)strand synthesis; (ii) that G:U pairs are tolerated transiently in (-)strand HP II; the lower stability of such a HP II is compensated by additional mutations outside HP II which suppress the competition of a rod-like structure; and (iii) that the reversions are generated spontaneously during (-)strand synthesis. Furthermore, the double-stranded structure of HP II is the essential element for short term replication of PSTVd but the exact sequence of the wild-type proves to be superior with regard to fitness and replicability of PSTVd.

[Effects of different articulator adjustments on motography traces]

In an articulator model the accuracy and conclusiveness of instant-picture motography has been studied. After correction for projection errors, system accuracy was found to be better than +/- 2 degrees in all projections.

Relation between fasting antroduodenal motility and transpyloric fluid movements

The effect of fasting antroduodenal motility on duodenogastric fluid movements was studied in 12 healthy volunteers. Antroduodenal motility was recorded using a multilumen manometry tube. Gastric emptying and secretion and the duodenogastric reflux of bile acids and marker were measured simultaneously by means of a marker dilution technique. Gastric emptying and acid secretion were higher in phase II than in phase I of the fasting motor activity cycle [median (range) 1.74 (1.2-4.2) ml/min vs. 0.90 (0.0-2.4) ml/min and 63.5 (6.4-115.0) vs. 37.9 (5.8-86.4) mumol/min, P less than 0.01]. The duodenogastric reflux rates of bile acids and marker were similar in all phases and showed large intra- and interindividual variations. There was no correlation between antroduodenal coordination during phase II motility and gastric emptying and duodenogastric reflux. It is concluded that the interdigestive motility pattern has moderate effects on fasting emptying of liquid gastric contents and on gastric secretion but no effects on duodenogastric reflux.

Intragastric bile acid concentrations in critically ill, artificially ventilated patients

Bile acids have experimentally been found to damage the gastric mucosa and, thus, may be involved in stress lesion pathogenesis. We therefore measured intragastric bile acid concentrations in 26 critically ill, artificially ventilated patients. The control group consisted of eight healthy volunteers, whose treatment was similar to that of the patients with respect to bed rest, enteral feeding, and administration of H2-blockers. Gastric contents were aspirated via a gastric tube every hour for 24 h. Patients had higher intragastric bile acid concentrations than healthy controls, whether fasting [median 1.3 mmol/L (range 0.7-2.5) versus 0.3 (0.2-0.5) (p less than 0.05)] or fed via a gastric tube [1.3 (0.4-4.0) versus 0.4 (0.2-0.7) (p less than 0.05)]. Physiotherapy, nursing, and drugs (opiates, benzodiazepines, dopamine, pirenzepine, and metoclopramide) had no detectable influence on intragastric bile acid concentrations and pH in patients. We conclude that patients at risk to develop stress lesions have largely increased gastric bile acid concentrations that probably are due to increased duodenogastric reflux. This might be relevant for stress lesion pathogenesis.

Is long-term esophageal pH monitoring of clinical value?

Two hundred eighty-nine patients with various chest symptoms were studied by interview for the presence and type of symptoms, and by long-term esophageal pH monitoring for acid reflux. One hundred eighty of the patients also had upper gastrointestinal endoscopy. There was significant correlation between the results of all three methods. pH monitoring was more sensitive (92.9% vs. 81.0%) and specific (41.3% vs. 23.9%), and classified more patients correctly (55.6% vs. 37.2%), than an interview by an experienced gastroenterologist when esophageal erosions were regarded as "gold standard" for pathologic reflux. Of all patients, 31.5% had unclear symptoms and therefore could not be diagnosed by interview alone. Forty nine percent of these had pathologic reflux on pH monitoring. Among the patients, 72.3% who had symptoms typical of reflux disease also had a pathologic result at pH monitoring. It is concluded that most patients with unambiguous symptoms of esophageal reflux can correctly be diagnosed by interview, but that esophageal pH monitoring has a role in the management of patients with less characteristic chest symptoms.

Effects of albuterol (salbutamol) on esophageal motility and gastroesophageal reflux in healthy volunteers

Orally or intravenously administered beta 2-adrenergic drugs have been found to inhibit esophageal motor function. Since inhalation of these drugs results in less systemic side effects, the present double-blind study was designed to investigate the influence of inhalation of the beta 2-adrenergic agonist albuterol (salbutamol) on esophageal motor function and gastroesophageal reflux in ten healthy volunteers. Esophageal motor function was recorded using a pneumohydraulically perfused multilumen manometry tube. Twenty-four-hour pH profiles were measured while the volunteers were ambulatory using a combined glass electrode connected to a portable recorder. Inhalation decreased neither lower esophageal sphincter pressure nor esophageal peristaltic amplitudes. Gastroesophageal reflux was similar on both occasions during inhalation of albuterol (3.1% [range, 1.0% to 25.5%] median upright time, with esophageal pH less than 4; and 0.1% [range, 0.0% to 10.7%] supine time) and during placebo treatment (3.6% [range, 1.6% to 19.8%] upright and 0.0% [range, 0.0% to 2.5%] supine time). Our data support the study of inhalation of beta 2-adrenergic drugs in asthmatic patients with accompanying gastroesophageal reflux.

Healthy controls have as much bile reflux as gastric ulcer patients

Data on duodenogastric reflux of bile in gastric ulcer are conflicting. We therefore measured intragastric bile acid concentration and its composition from individual bile acids, duodenogastric bile acid reflux rate, gastric emptying rate, and secretion rates of volume and acid in 30 patients with gastric ulcer and in 66 healthy controls, both in the fasting state and after feeding a liquid meal. Patients had higher gastric bile acid concentrations (p less than 0.05) than controls in the fasting state, but the overlap between the groups was considerable. In fasting patients with corpus ulcer, gastric secretion rates were significantly decreased when compared with controls. There was no difference between patients and controls with respect to gastric emptying rate, bile acid reflux rate, intragastric amount of bile acids, and bile acid composition in the fasting state. Postprandially, all parameters tested were similar in patients and controls. Controls showed high reflux rates with similar frequency as did ulcer patients. We conclude that increased gastric bile acid concentrations in the fasting stomach of patients with gastric ulcer are the result of gastric hyposecretion and not of increased reflux. They probably are pathogenetically irrelevant.

Optimal thresholds, sensitivity, and specificity of long-term pH-metry for the detection of gastroesophageal reflux disease

Long-term esophageal pH-metry has become the preferred test to quantify acid gastroesophageal reflux, but its accuracy in separating physiologic from pathological reflux is not well defined. To establish optimal thresholds of 24-h pH-metry, we studied 45 patients with clinically proven gastroesophageal reflux disease and 42 healthy volunteers. Twenty-four-hour esophageal pH was measured while the subject was ambulatory, using a combined glass electrode connected to a portable recorder. Percentage of time with esophageal pH less than 4, the number and mean duration of reflux episodes, the number of episodes lasting longer than 5 min, and the duration of the longest episode were calculated for periods of upright and supine body position, respectively. Discriminant analysis and receiver-operating-characteristic analysis were used to define optimal thresholds. A maximum of sensitivity (93.3%) and specificity (92.9%) was obtained using receiver-operating-characteristic analysis with the following criteria. Only percentage of time with esophageal pH less than 4 is considered. A subject is classified as "normal" if both values for the upright and supine body position are below the thresholds, otherwise the subject is classified as "pathological." The thresholds are 10.5% of time with esophageal pH less than 4 for the upright position and 6.0% for the supine position. Within the limits of this retrospective study, it is concluded that rather simple criteria yield a high diagnostic accuracy in the evaluation of long-term esophageal pH-metry. Nevertheless, a prospective and independent confirmation of these criteria is needed.

Influence of smoking and esophageal intubation on esophageal pH-metry

The effect of cigarette smoking on gastroesophageal reflux and the effect of the pH electrode on salivary secretion and swallowing frequency were studied in 30 healthy volunteers (15 habitual smokers, 15 non-smokers) and in 10 smoking patients with proven gastroesophageal reflux disease. Twenty-four-hour pH profiles were measured while the subjects were ambulatory using a combined glass electrode connected to a portable recorder. In 8 of the smoking volunteers, swallowing frequency and salivary secretion were measured, both when smoking and when not. Smokers had more reflux episodes than nonsmokers [median per hour 2.8 (range 0.4-7.1) for the upright body position and 0.5 (range 0.0-1.7) for the supine body position vs. 1.4 (range 0.0-2.1) upright and 0.0 (range 0.0-0.7) supine, p less than 0.01], but the total time of exposure of the esophageal mucosa to acid was affected neither by the status of being a smoker nor by actual smoking. Nasopharyngeal intubation with the pH electrode did not affect the swallowing frequency, but it increased salivary secretion two-to threefold for a period of 4 h. Six hours after introduction of the pH electrode and later, salivary flow was similar to baseline. It is concluded that smoking and nasopharyngeal intubation does not adversely affect the results of 24-h pH-metry.

Bile salt reflux after cholecystectomy

Gastric bile salt concentrations, the rates of bile salt reflux, gastric emptying, and gastric volume secretion were measured in 9 women with previous cholecystectomy and 13 unoperated female controls. The subjects were studied using a marker technique with gastric intubation both fasting and after gastric instillation of a mixed liquid meal. Cholecystectomy was without effect on gastric emptying and gastric volume secretion. Cholecystectomized patients had increased bile salt reflux rates (1.4 +/- 0.4 versus 0.6 +/- 0.2 mumol/min) and gastric bile concentrations (1753 +/- 266) versus 441 +/- 114 mumol/l) in the fasting state, but lower rates (0.3 +/- 0.3 versus 3.4 +/- 0.9 mumol/min) and concentrations (131 +/- 46 versus 496 +/- 123 mumol/l) after feeding. These findings can be explained by the changes of bile flow into the duodenum induced by cholecystectomy.

[Biotransformation of fentanyl. II. Acute drug interactions in rats and men (author's transl)]

Rat tissue homogenates were used to study fentanyl biotransformation. The liver was shown to be the most important metabolizing organ, whereas extrahepatic metabolism occurred only to a minor degree in the kidneys. The products of oxidative desalkylation, phenylacetic acid and norfentanyl, could be identified as well as small amounts of p-hydroxy-(phenethyl)fentanyl, which is pharmacologically still active. Major sex differences were observed, male rats showing nearly twice as much activity as female animals. Several anaesthetic agents, often used in combination with fentanyl, were tested with respect to their influence on fentanyl metabolism. Most of them caused an inhibition of biotransformation and/or variations in product distribution, when they were added to in-vitro incubations or given to the animals prior to enzyme preparation. This experimental design proved to be useful as a screening method to predict metabolic drug interactions. Halothane and enflurane, which are strong inhibitors in rats, were demonstrated to delay fentanyl metabolism in man, too. Fentanyl plasma levels under halothane anaesthesia were found to be more than twice as high as during neuroleptanaesthesia. The importance of other agents, e.g. ketamine, promethazine or local anaesthetics, remains to be examined. Variations of biotransformation reactions among patients as well as the reported drug interactions might explain some differences in fentanyl blood concentrations reported in the past, but must also be taken into account when intensity and duration of effects or side-effects are discussed.