Are there differences in the use of selective serotonin reuptake inhibitors and tricyclic antidepressants? A prescription database study

AIM

The aim of the present study was to analyse the utilisation of antidepressants (ADs) and to compare the utilisation of the various ADs with special reference to duration of treatment courses.

METHOD

From the Odense Pharmacoepidemiologic Database (OPED), all users of and prescriptions for ADs in the County of Funen, Denmark (about 470,000 inhabitants), were identified for each year from 1992 to 1997 (6 years). Duration of treatment courses was calculated for the first incident period of continuous use of one AD and was compared for the various ADs using Kaplan-Meiers survival statistics with log rank tests. Continuous use was defined as use of a minimum of one tablet per day. Furthermore, the proportion of users presenting only one prescription was determined for each AD.

RESULTS

In total, 37,598 patients presented 392,524 prescriptions during 1992-1997. The 1-year prevalence rose from 2.1% to 4.1% in 1997 and the incidence was 1.3% in 1997. The 1-year prevalence increased with age up to 16.5% in 1997 for patients aged 90 years or older. Citalopram was the most-used AD, but there were still a considerable number of patients commencing treatment with TCAs in 1997. Median duration of treatment courses was 196 days for TCAs versus 120 days for SSRIs (P < 0.0001). Duration of treatment courses increased with age. The proportion of users presenting only one prescription was 22% for the SSRIs versus 33% for tricyclic antidepressants (TCAs).

CONCLUSION

This study showed that the use of ADs continues to increase because of the increase in the use of the new ADs. There was, however, still a considerable number of patients who started on TCA treatment in 1997. For repeated prescriptions, TCAs were used for longer times than SSRIs. In the very old, there was an apparently inappropriate high use of ADs.

Pharmacovigilance based on prescription databases

Prescription databases are indispensible in drug safety research and surveillance. For suspected rare serious adverse drug reactions, the confirmation and quantitative risk assessment requires proper epidemiological studies. Often prescription databases provide the information on drug exposure for such studies. Aberrant drug utilization in terms of overuse, underuse, polypharmacy etc. may be a threat to the health of the patient, and these aspects can best be studied by prescription databases. In cases of international drug safety alerts, prescription databases may provide information required for rational actions to be taken.

A combined analysis of double-blind trials of the efficacy and tolerability of doxazosin-gastrointestinal therapeutic system, doxazosin standard and placebo in patients with benign prostatic hyperplasia

OBJECTIVE

To report an integrated analysis of two previous studies fully characterizing the clinical utility of the controlled-release gastrointestinal therapeutic system (GITS) formulation of doxazosin in the treatment of benign prostatic hyperplasia (BPH).

PATIENTS AND METHODS

Two pivotal randomized, double-blind studies of doxazosin GITS for BPH were assessed by an integrated analysis. Both studies included a 2-week washout period, a 2-week single-blind placebo run-in phase, and a 13-week double-blind treatment phase. One study compared doxazosin GITS, doxazosin standard (-S) and placebo in 795 men; the other compared doxazosin GITS and doxazosin-S in 680 men. Doxazosin GITS was initiated at 4 mg once daily and titrated to 8 mg once daily after 7 weeks, and doxazosin-S was initiated at 1 mg once daily and titrated to a maximum of 8 mg once daily over 7 weeks as needed to achieve optimal symptom control. The primary outcome measures were mean changes from baseline to the final visit for the International Prostate Symptom Score (IPSS) and maximum urinary flow rate (Qmax) in the per-protocol population. Numerous symptom- and urinary-related secondary outcomes were assessed, as were effects of therapy on male erectile dysfunction measured using the International Index of Erectile Function (IIEF) in one study.

RESULTS

Both doxazosin GITS and doxazosin-S significantly improved the symptoms of BPH, as shown by a 45% reduction for each in total IPSS from baseline to final visit, compared with a 34% reduction in patients on placebo. Doxazosin GITS and doxazosin-S produced comparable improvements in Qmax that were significantly greater than with placebo, with a greater improvement sooner after treatment with doxazosin GITS than with doxazosin-S. Nearly half of the patients on doxazosin GITS had symptom relief at the 4-mg starting dose. A similar number of patients in both doxazosin groups were titrated to the maximum dose. Secondary outcomes were consistent with the primary effects. Both doxazosin GITS and doxazosin-S produced significant improvements in sexual function according to IIEF scores among those with dysfunction at baseline. The overall incidence of adverse events was similar among patients treated with doxazosin GITS and placebo, and slightly lower than those on doxazosin-S. There was no apparent difference in the type of adverse events reported for the two formulations of doxazosin, although most adverse events were reported at a lower frequency with doxazosin GITS.

CONCLUSION

Doxazosin GITS is significantly more effective than placebo in reducing the clinical symptoms of BPH and improving Qmax, and as effective as doxazosin-S. Both doxazosin formulations improved sexual function in patients with BPH and sexual dysfunction at baseline. Doxazosin GITS produced a therapeutic effect equivalent to that of doxazosin-S, but with fewer titration steps and a slightly lower overall incidence of adverse events.

[Reconstruction of upper esophagus after treatment of cancer in the larynx, hypopharynx and upper esophagus]

INTRODUCTION

Two new methods of reconstructing the proximal oesophagus after resection of cancer in the larynx, hypopharynx, or proximal oesophagus are examined.

MATERIAL AND METHOD

Between 1991 and 1996, 12 patients were operated on after initial irradiation. The reconstructions were done by a microsurgical technique, with eight jejunum transplants and four tubulated radial forearm flaps. The records were reviewed retrospectively.

RESULTS

The patients were hospitalised for about a month and were able to swallow soft food three weeks after the operation. Most patients achieved pain palliation and a good swallowing function for a period of three to more than 24 months, until relapse. All patients except two died between five and 21 months after the operation.

DISCUSSION AND CONCLUSION

Both techniques give an acceptable swallowing function until relapse. The size of the defect indicates the choice of flap. They are also suitable in such situations as complex fistula formation, congenital atresia, and the after-effects of corrosion.

In vivo secretory potential and the effect of combination therapy with octreotide and cabergoline in patients with clinically non-functioning pituitary adenomas

The secretory capacity, in vivo, of clinically non-functioning pituitary adenomas may possibly predict tumour volume reduction during intensive medical therapy. Ten patients (mean (range) 53 years (26-73)) with clinically non-functioning macroadenomas, > or = 10 mm were studied. The secretory capacity of the adenomas was examined using basal, NaCl and TRH-stimulated LH, FSH and alpha-subunit levels. The effect on tumour volume of 6 months' therapy with the combination of a somatostatin analogue, octreotide 200 microg x 3/day and a dopamine-D2-agonist, cabergoline 0.5 mg x 1/day was studied. The basal LH, FSH and alpha-subunit levels were determined before and during 6 months' therapy with octreotide and cabergoline, and MR scans were used to evaluate tumour volume before and during this period of therapy. Octopus-perimetry was used to examine the visual fields. A reduction in tumour volume (mean +/- SEM (range); 30% +/- 4% (18-46%)) during 6 months of combination therapy with octreotide and cabergoline was recorded only in patients with in vivo secretory potential. Tumour volume was not reduced in four patients: in three of these patients it remained unchanged while in one patient it was observed to have increased (by 14%). Of the six patients with pretherapy secretory capacity, one displayed a very high basal level of alpha-subunit (74 microg/l) despite unmeasurable levels of LH and TSH, and an FSH-level of 1 IU/l. The other five patients presented paradoxical LH, FSH and/or alpha-subunit responses to TRH. A reduction in basal levels of LH, FSH and/or alpha-subunit was observed in all six patients, and the maximum reduction of at least one of the hormonal levels was 66% +/- 7% (50-98%). The basal levels of LH, FSH and alpha-subunit in the 10 patients were (mean +/- SEM (range)), 3.0 IU/l +/- 1.0 (0.0-7.4), 12.7 IU/l +/- 5.0 (0.0-39.0) and 9.0 IU/l +/- 7.0 (0.2-74.0). During six months of therapy with octreotide and cabergoline, the basal levels of LH, FSH and alpha-subunit were reduced by > or = 50% in seven patients - including the six patients with in vivo secretion prior to therapy. No new visual field defects were detected during therapy and no deterioration of existing visual field defects was recorded. The medical therapy was well tolerated. The in vivo basal and TRH-stimulated secretory capacity of LH, FSH and alpha-subunit predicted tumour reduction following intensive medical therapy in all of our patients with non-functioning pituitary adenomas.

In vitro human tissue models in risk assessment: report of a consensus-building workshop

Advances in the technology of human cell and tissue culture and the increasing availability of human tissue for laboratory studies have led to the increased use of in vitro human tissue models in toxicology and pharmacodynamics studies and in quantitative modeling of metabolism, pharmacokinetic behavior, and transport. In recognition of the potential importance of such models in toxicological risk assessment, the Society of Toxicology sponsored a workshop to evaluate the current status of human cell and tissue models and to develop consensus recommendations on the use of such models to improve the scientific basis of risk assessment. This report summarizes the evaluation by invited experts and workshop attendees of the current status of such models for prediction of human metabolism and identification of drug-drug interactions, prediction of human toxicities, and quantitative modeling of pharmacokinetic and pharmaco-toxicodynamic behavior. Consensus recommendations for the application and improvement of current models are presented.

[Surgical treatment of hypernasality in Denmark]

OBJECTIVE

A palatopharyngoplasty is a widely used operation performed to diminish hypernasality. The purpose of this study was to assess the results of the palatopharyngoplasties and to estimate if the type of cleft or other structural defect influenced these results.

MATERIAL AND METHOD

This is a retrospective study of the patient records from 1/1-1991 to 1/11-1996 comprising 297 operations on which 284 records were available. The results of the operations were evaluated by speech pathologists who have rated the nasality before and after the palatopharyngoplasties.

RESULTS

Following operation 90.1% of the patients obtained normal resonance or reduced hypernasality. The type of cleft or other structural defect did not influence the results.

DISCUSSION

Palatopharyngoplasty is an effective operative procedure in the treatment of hypernasality, regardless of the type of cleft or structural defect. To further optimize the treatment a higher level of standardization is recommended.

Double-blind trial of the efficacy and tolerability of doxazosin in the gastrointestinal therapeutic system, doxazosin standard, and placebo in patients with benign prostatic hyperplasia

BACKGROUND

The alpha(1)-blocker doxazosin mesylate is an established efficacious and welltolerated treatment for benign prostatic hyperplasia (PBH). However, its clinical utility can be limited by the need for multiple titration steps, starting at an initial dose of 1 mg, increased up to 8 mg once daily, to achieve optimal therapeutic response. A new controlled-release gastrointestinal therapeutic system (GITS) formulation of doxazosin mesylate enhances the pharmacokinetic profile and drug delivery rate, reducing the plasma doxazosin mesylate peak-to-trough ratio and minimizing the need for titration.

OBJECTIVE

A study was conducted to assess the effects of doxazosin GITS 4 or 8 mg once daily, doxazosin standard 1 mg to 8 mg once daily, and placebo, in 795 men with BPH. This randomized, double-blind, multicenter Scandinavian study included a 2-week washout period, 2-week single-blind placebo run-in phase, and 13-week double-blind treatment phase. Doxazosin GITS was initiated at 4 mg once daily and titrated to 8 mg once daily after 7 weeks, if indicated, and doxazosin standard was initiated at 1 mg once daily, titrated to 2 mg after 1 week, to 4 mg at 3 weeks, and to 8 mg at 7 weeks if indicated, to achieve symptom control. The primary outcome measures were mean changes from baseline to the final visit for International Prostate Symptom Score (I-PSS) and maximum urinary flow rate adjusted for baseline values.

RESULTS

Both doxazosin GITS and doxazosin standard significantly improved the symptoms of BPH, as evidenced by least-squares mean reductions in total I-PSS of -8.0+/-0.3 and -8.4+/-0.3 from baseline, respectively, compared with a reduction of -6.0+/-0.4 in patients on placebo. Doxazosin GITS and doxazosin standard produced clinically comparable improvements in maximum urinary flow rates, with a greater improvement observed earlier following treatment with doxazosin GITS than with doxazosin standard. Both active treatments produced significantly greater increases in maximum urinary flow rate compared with placebo. Nearly half of the patients on doxazosin GITS achieved symptom relief at the 4-mg starting dose. A similar number of patients in both doxazosin groups were titrated to the maximum dose of 8 mg for both formulations. The overall incidence of adverse events was similar among patients treated with doxazosin GITS and placebo, and slightly higher in those on doxazosin standard. There was no apparent difference in the type of adverse events reported for the two formulations of doxazosin, although most adverse events were reported at a lower frequency with doxazosin GITS.

CONCLUSIONS

Doxazosin GITS is significantly more effective than placebo in reducing the clinical symptoms of BPH and improving maximum urinary flow rate, and as effective as doxazosin standard. A therapeutic effect equivalent to that of doxazosin standard was achieved with doxazosin GITS with fewer titration steps, in a manner that appeared to be better tolerated. Because treatment with doxazosin GITS starts with an effective dose for many patients, it is likely that this clinical profile will result in the need for fewer patient visits than with doxazosin standard therapy.

Application of a hybrid CFD-PBPK nasal dosimetry model in an inhalation risk assessment: an example with acrylic acid

The available inhalation toxicity information for acrylic acid (AA) suggests that lesions to the nasal cavity, specifically olfactory degeneration, are the most sensitive end point for developing a reference concentration (RfC). Advances in physiologically based pharmacokinetic (PBPK) modeling, specifically the incorporation of computational fluid dynamic (CFD) models, now make it possible to estimate the flux of inhaled chemicals within the nasal cavity of experimental species, specifically rats. The focus of this investigation was to apply an existing CFD-PBPK hybrid model in the estimation of an RfC to determine the impact of incorporation of this new modeling technique into the risk assessment process. Information provided in the literature on the toxicity and mode of action for AA was used to determine the risk assessment approach. A comparison of the approach used for the current U.S. Environmental Protection Agency (U.S. EPA) RfC with the approach using the CFD-PBPK hybrid model was also conducted. The application of the CFD-PBPK hybrid model in a risk assessment for AA resulted in an RfC of 79 ppb, assuming a minute ventilation of 13.8 l/min (20 m(3)/day) in humans. This value differs substantially from the RfC of 0.37 ppb estimated for AA by the U.S. EPA before the PBPK modeling advances became available. The difference in these two RfCs arises from many factors, with the main difference being the species selected (mouse vs. rat). The choice to conduct the evaluation using the rat was based on the availability of dosimetry data in this species. Once these data are available in the mouse, an assessment should be conducted using this information. Additional differences included the methods used for estimating the target tissue concentration, the uncertainty factors (UFs) applied, and the application of duration and uncertainty adjustments to the internal target tissue dose rather than the external exposure concentration.

Contacts to the health care system prior to suicide: a comprehensive analysis using registers for general and psychiatric hospital admissions, contacts to general practitioners and practising specialists and drug prescriptions

OBJECTIVE

The purpose of this study was to describe suicides' contacts with various parts of the health-care system.

METHOD

Data on 472 people who committed suicide in a Danish County (Funen) in the period of April 1 1991 to December 31 1995 were searched in the Danish Psychiatric Central Register, the National Patient Register, the National Health Insurance and Odense Pharmacoepidemiologic Database.

RESULTS

In total, 97.5% of the suicides were recaptured in at least one of these registers. Forty-two per cent had been hospitalized in psychiatric departments. Within the last month before death, 66% consulted a general practitioner, 13% and 7%, respectively, were discharged from a psychiatric hospital and general hospital.

CONCLUSION

The registers used provided a comprehensive registry-based description of suicides' contacts with the health-care system. The most prominent features were the high prevalence of psychiatric morbidity and the high rate of contacts with GPs close to suicide.

Deviations from evidence-based prescribing of non-steroidal anti-inflammatory drugs in three European regions

OBJECTIVE

We examined to what extent the evidence of the relative gastrointestinal toxicity with non-steroidal anti-inflammatory drugs (NSAIDs) was implemented in clinical practice in Bologna, Italy, Funen, Denmark, and Stockholm, Sweden, areas with accurate computerised information on prescriptions purchased by defined populations.

METHODS

We ranked each NSAID by purchased volume in defined daily doses during September 1996 and compared it with the ranking of gastrointestinal complications from a meta-analysis of controlled epidemiological studies published between 1986 and 1994. We restricted our comparison to those NSAIDs that accounted for 90% of the use and within this DU90% segment we determined the proportion of "high risk" (azapropazone, ketoprofen, piroxicam) and "low risk" (ibuprofen, diclofenac) drugs with respect to gastrointestinal toxicity.

RESULTS

In Funen, Denmark, we found the best NSAID profile (63% low risk/11% high risk) while Bologna, Italy, had the other extreme (26% low risk/38% high risk), with Stockholm, Sweden, in between (43% low risk/20% high risk).

CONCLUSION

Our study suggests that factors other than evidence-based medicine had a dominating impact on the use of prescription NSAIDs in 1996.

[Do health personnel talk about passive smoking with parents of small children?]

INTRODUCTION

Almost seven out of ten parents who smoke state that they have never received information on passive smoking from health personnel when they bring their children in for routine medical examination. We examined what GPs, doctors and nurses at mother-and-child clinics and midwives reported.

MATERIAL AND METHODS

A self-administered questionnaire focusing on practice as regards the matter of passive smoking and children was mailed to a representative sample of 1050 GPs, the senior midwives at Norway's 77 maternity departments, 492 senior public health nurses, and health personnel at 1024 mother-and-child clinics. The response rate varied from 71% (GPs) to 82% (senior midwives).

RESULTS

70% of the personnel at mother-and-child clinics less often than "always" ask about exposure to passive smoking. 60% of the senior midwives report that the department's personnel less than "to a large extent" allocate time to talk with parents about passive smoking. 40% of the GPs and 50% of the paediatricians say that they "never" bring up the matter of passive smoking when they examine small children and do not know whether members of the household smoke or not. The rest of the GPs bring up the matter in 46% of consultations and the rest of the paediatricians in 63% of consultations. When the child has symptoms that can be associated with passive smoking, the GPs discuss the parents' smoking habits in 88% of the consultations and paediatricians in 100% of consultations.

INTERPRETATION

Only to a small extent do health personnel use their opportunities of motivating parents to change their smoking habits for the sake of the health of their children. Smoking is only brought up by professionals as a matter routine when the children develop symptoms of exposure to tobacco smoke.

Lack of adherence to lipid-lowering drug treatment. A comparison of utilization patterns in defined populations in Funen, Denmark and Bologna, Italy

AIMS

The objective was to explore differences in lipid-lowering drug (LLD) prescribing in Italy and Denmark.

METHODS

We used two geographical areas with computerized drug prescription records in defined populations, one in Funen, Denmark with 500 000 inhabitants, the other in Bologna, Italy with 400 000 inhabitants. Prescriptions for patients who had purchased a LLD from 1994 until 1996 were retrieved as well as coprescriptions of antidiabetic and cardiovascular drugs as markers for diabetes and cardiovascular disease. Only patients surviving and remaining in the area were included. Compliance was defined as percentage of DDDs purchased divided by the number of days within the time window. The limit between good and poor compliance was set at 82%.

RESULTS

In Bologna, LLD consumption measured in DDD increased by 41% and in Funen by 129%. Annual prevalence increased from 36.9 to 46.3 users/1000 inhabitants from 1994 to 1996 and from 3.2 to 6.6 users/1000 inhabitants in Bologna and Funen, respectively. From 1995 to 1996, the incidence of use decreased slightly in Bologna from 19.3 to 18. 8/1000 inhabitants/year, whereas in Funen the incidence increased from 1.8 to 2.3/1000 inhabitants/year. In Bologna 48% and in Funen 91% of users persisted with treatment for 2 years or longer. In Bologna, 7% and in Funen 45% were good compliers. In Bologna, 61% and in Funen, 72% received other drugs indicating cardiovascular or diabetic comorbidity.

CONCLUSIONS

Patterns of use differed substantially between the two areas. In contrast with Funen, where long-term use was common, Bologna LLD use was sporadic. Based on a higher rate of coprescription, LLDs seemed to be used for secondary prevention to a higher extent in Funen than in Bologna. In Funen it appeared that the correct patients, but an insufficient number of them, were being treated adequately according to guidelines. The higher discontinuation rate of lipid lowering drugs in the Bologna area indicates that a large proportion of patients use these drugs for too short a period of time to benefit from treatment. Since society's health care resources are limited it is difficult to justify public funding of these medications without at the same time giving appropriate attention to these problems.

[Giant urinary bladder stone]

We report a 660 gram stone in the urinary bladder of an otherwise healthy 69 year old male. The stone gave rise to only minor subjective symptoms, but urograms revealed dilatation of both the ureters. The stone was removed by open cystolithotomy. Giant bladder stones are rare in modern urologic practice. In earlier centuries, however, bladder stone formation was a common urinary tract disease with need for surgery. A brief survey of historical lithotomy methods is given.

Effects of citicoline combined with thrombolytic therapy in a rat embolic stroke model

BACKGROUND AND PURPOSE

We sought to evaluate the effects of the combination of cytidine-5'-diphosphocholine (citicoline) and thrombolysis on infarct size, clinical outcome, and mortality in a rat embolic stroke model.

METHODS

Eighty-three Sprague-Dawley rats were embolized in the carotid territory with a single fibrin embolus and randomly assigned to the following treatment groups: (1) control (saline), (2) citicoline 250 mg/kg, (3) citicoline 500 mg/kg, (4) recombinant tissue plasminogen activator (rtPA) 5 mg/kg, (5) rtPA 5 mg/kg plus citicoline 250 mg/kg, and (6) rtPA 5 mg/kg plus citicoline 500 mg/kg. rtPA was administered as a continuous intravenous infusion over 45 minutes starting 45 minutes after embolization; citicoline was given intraperitoneally 30 minutes and 24, 48, and 72 hours after embolization. At 96 hours, the brains were fixed and stained by hematoxylin-eosin, and infarct volumes were measured. Neurological scores were determined daily.

RESULTS

The median infarct size, measured as percentage of the affected hemisphere, in the control group was 37% (interquartile range, 26% to 69%) compared with 22% (5% to 52%; P=NS) in group 2, 11% (5% to 34%; P=NS) in group 3, 24% (12% to 31%; P=NS) in group 4, 11% (3% to 22%; P=0.02) in the combined group 5, and 19% (9% to 51%; P=NS) in group 6. The infarct size was significantly reduced in the combined citicoline+rtPA-treated groups to a median of 13% (5% to 30%; P<0.01). Citicoline 500 mg/kg and citicoline combined with rtPA also promoted functional recovery.

CONCLUSIONS

These results demonstrate that the combination of low-dose citicoline and rtPA significantly reduced infarct size in this focal ischemia model.

A bacterial haloalkane dehalogenase gene as a negative selectable marker in Arabidopsis

The dhlA gene of Xanthobacter autotrophicus GJ10 encodes a dehalogenase which hydrolyzes dihalo- alkanes, such as 1, 2-dichloroethane (DCE), to a halogenated alcohol and an inorganic halide (Janssen et al. 1994, Annu. Rev. Microbiol. 48, 163-191). In Xanthobacter, these alcohols are further catabolized by alcohol and aldehyde dehydrogenase activities, and by the product of the dhlB gene to a second halide and a hydroxyacid. The intermediate halogenated alcohols and, in particular, the aldehydes are more toxic than the haloalkane substrates or the pathway products. We show here that plants, including Arabidopsis, tobacco, oil seed rape and rice, do not express detectable haloalkane dehalogenase activities, and that wild-type Arabidopsis grows in the presence of DCE. In contrast, DCE applied as a volatile can be used to select on plates or in soil transgenic Arabidopsis which express dhlA. The dhlA marker therefore provides haloalkane dehalogenase reporter activity and substrate dependent negative selection in transgenic plants.

The effects of endogenous opioids and cortisol on thyrotropin and prolactin secretion in patients with Addison's disease

This study assessed the controversial role of endogenous opioids and cortisol in the regulation of TSH and PRL secretion in humans. Seven euthyroid male patients with Addison's disease were studied four times, with an interval of 1-3 months, as follows: 1) during normocortisolism [graduated infusion of hydrocortisone, 0.4 mg/kg, over 19.5 h]; 2) normocortisolism and coadministration of naloxone, at 25 microg/kg x h during the last 6.5 h; 3) hypocortisolism (24 h withdrawal of hydrocortisone, followed by 19.5 h saline infusion); and 4) hypocortisolism plus naloxone administration. The TSH and PRL levels were measured every 15 min, from 0800-1530 h. A TRH test was performed at 1300 h and 1400 h (10 microg and 200 microg of TRH, respectively). The mean TSH level increased significantly during hypocortisolism, compared with normocortisolism (1.78 +/- 0.04 vs. 0.84 +/- 0.02 mU/L; P < 0.001). The administration of naloxone suppressed the TSH levels during hypo- and normocortisolism (1.78 +/- 0.04 vs. 1.50 +/- 0.03 and 0.84 +/- 0.02 vs. 0.61 +/- 0.02 mU/L, respectively; P < 0.001). During hypocortisolism, the TSH responses to small and high doses of TRH were significantly higher than during normocortisolism (P < 0.02). Naloxone had no effect on the TSH responses to TRH, neither during hypo- nor during normocortisolism. The mean PRL level increased significantly during hypocortisolism, compared with normocortisolism (5.8 +/- 0.4 vs. 3.6 +/- 0.2 microg/L; P < 0.001), and naloxone induced an increase in PRL levels both during hypo- and normocortisolism (7.1 +/- 0.7 vs. 4.7 +/- 0.5 microg/L, respectively; P < 0.01). The PRL responses to TRH were similar during hypo- and normocortisolism and without any change during opioid receptor blockade. In conclusion, cortisol suppressed basal TSH and PRL secretion and reduced the sensitivity of the thyrotrophs to TRH, without affecting the PRL response to TRH. Our results suggest that endogenous opioids act at the hypothalamic level to stimulate TSH secretion and to suppress the PRL secretion, but these results argue against an essential role of endogenous opioids in the physiological regulation of TSH and PRL secretion in humans.

Apoptosis and the Bcl-2 gene family -- patterns of expression and prognostic value in stage I and II follicular center lymphoma

PURPOSE

The prognostic significance of spontaneous levels of apoptosis and Bcl-2, Bax, and Bcl-x protein expression in follicular center lymphoma (FCL) is unknown. The objectives of this retrospective study were (1) to investigate the relationship between pretreatment apoptosis levels and long-term treatment outcome in patients with Stage I and II FCL; (2) to define the incidence and patterns of Bax and Bcl-x protein expression in human FC; and (3) to determine the relationship of Bcl-2, Bax, and Bcl-x expression with spontaneous apoptosis levels and clinical outcome in localized FCL.

METHODS AND MATERIALS

Between 1974 and 1988, 144 patients with Stage I or II FCL were treated. Hematoxylin and eosin (H & E) stained tissue sections of pretreatment specimens were retrieved for 96 patients. Treatment consisted of regional radiation therapy (XRT) for 25 patients, combined modality therapy (CMT) consisting of combination chemotherapy and XRT for 57 patients, and other treatments for 14 patients. Median follow-up for living patients was nearly 12 years. The apoptotic index (AI) was calculated by dividing the number of apoptotic cells by the total number of cells counted and multiplying by 100. Expression of Bcl-2, Bax, and Bcl-x proteins was assessed using immunohistochemistry.

RESULTS

The mean and median AI values for the entire group were 0.53 and 0.4, respectively (range: 0-5.2). The AI strongly correlated with cytologic grade, with mean AI values of 0.25 for grade 1, 0.56 for grade 2, and 0.84 for grade 3 (p < 0.0005; Kendall correlation). A positive correlation was present between grouped AI and grouped mitotic index (MI) (p = 0.014). For patients treated with CMT, an AI < 0.4 correlated with improved freedom from relapse (FFR) p = 0.0145) and overall survival (OS) (p = 0.0081). An AI < 0.4 did not correlate with clinical outcome for the entire cohort or for patients receiving XRT only. Staining of tumor follicles for the Bcl-2 protein was positive, variable, and negative in 73%, 15%, and 12% of cases, respectively. Positive staining of tumor follicles was observed in 96% of cases for both the Bax and Bcl-x proteins. Expression of Bcl-2, Bax, or Bcl-x did not correlate with AI or clinical outcome.

CONCLUSION

The level of spontaneous apoptosis in pretreatment specimens correlates with cytologic grade of FCL and is a significant predictor of FFR and OS for patients with localized FCL receiving CMT.

Cerebral astrocyte response to micromachined silicon implants

The treatment of neurologic disorders and the restoration of lost function due to trauma by neuroprosthetic devices has been pursued for over 20 years. The methodology for fabricating miniature devices with sophisticated electronic functions to interface with nervous system tissue is available, having been well established by the integrated circuit industry. Unfortunately, the effectiveness of these devices is severely limited by the tissue reaction to the insertion and continuous presence of the implant, a foreign object. This study was designed to document the response of reactive astrocytes in the hope that this information will be useful in specifying new fabrication technologies and devices capable of prolonged functioning in the brain. Model probes fabricated from single crystal silicon wafers were implanted into the cerebral cortices of rats. The probes had a 1 x 1-mm tab, for handling, and a 2-mm-long shaft with a trapezoidal cross-section (200-microm base, 60microm width at the top, and 130 microm height). The tissue response was studied by light and scanning electron microscopy at postinsertion times ranging from 2 to 12 weeks. A continuous sheath of cells was found to surround the insertion site in all tissue studied and was well developed but loosely organized at 2 weeks. By 6 and 12 weeks, the sheath was highly compacted and continuous, isolating the probe from the brain. At 2 and 4 weeks, the sheath was disrupted when the probe was removed from the fixed tissue, indicating that cells attached more strongly to the surface of the probe than to the nearby tissue. The later times showed much less disruption. Scanning electron microscopy of the probes showed adherent cells or cell fragments at all time points. Thus, as the sheath became compact, the cells on the probe and the cells in the sheath had decreased adhesion to each other. Immunocytochemistry demonstrated that the sheath was labeled with antibodies to glial fibrillary acidic protein (GFAP), an indicator for reactive gliosis. The tissue surrounding the insertion site showed an increased number of GFAP-positive cells which tended to return to control levels as a function of time after probe insertion. It was concluded that reactive gliosis is an important part of the process forming the cellular sheath. Further, the continuous presence of the probe appears to result in a sustained response that produces and maintains a compact sheath, at least partially composed of reactive glia, which isolates the probe from the brain.

Drug-specific characteristics of thrombocytopenia caused by non-cytotoxic drugs

OBJECTIVE

To analyse drug-specific clinical characteristics and to investigate the possible influence of epidemiological and other factors on thrombocytopenia induced by selected non-cytotoxic drugs.

METHODS

A retrospective analysis of drug-induced thrombocytopenia reported to the Danish Committee on Adverse Drug Reactions. One-hundred and ninety-two cases induced by the most frequently reported drugs were included and analysed from data extracted from report forms and discharge summaries.

RESULTS

Pronounced drug-specific differences in the clinical appearance of thrombocytopenia were registered. Severe thrombocytopenia with haemorrhagic manifestations was reported following exposure to gold salts, non-steroid anti-inflammatory drugs, sulfonamide antibiotics, cinchona alkaloids and vaccines. Valproic acid-induced thrombocytopenia was dose-dependent. The differences were primarily determined by the drug itself and also by its usage pattern. No specific patient-related factor responsible for the heterogeneity of the clinical appearance of the adverse reaction was identified. Factors related to the physician, such as monitoring recommendations or level of attention towards the adverse reaction, seemed to be of little significance.

CONCLUSION

The primary determinant of the clinical characteristics of thrombocytopenia induced by noncytotoxic drugs is the offending drug.