[Extensive eosinophilic pulmonary infiltrates in a depressive patient treated with maprotiline]

A 74 year old man developed progressive dyspnea under treatment with the tetracyclic antidepressant maprotiline for three months. A chest x-ray revealed extended pulmonary infiltrates. Marked eosinophilia of the periperal blood was found (up to 2300/microliter). Rapid clinical and radiological improvement was observed solely by withholding the drug. The eosinophil count retourned to normal within a few weeks. The possible pathogenesis is discussed and the literature reviewed.

An alpha-actinin binding site of zyxin is essential for subcellular zyxin localization and alpha-actinin recruitment

The LIM domain protein zyxin is a component of adherens type junctions, stress fibers, and highly dynamic membrane areas and appears to be involved in microfilament organization. Chicken zyxin and its human counterpart display less than 60% sequence identity, raising concern about their functional identity. Here, we demonstrate that human zyxin, like the avian protein, specifically interacts with alpha-actinin. Furthermore, we map the interaction site to a motif of approximately 22 amino acids, present in the N-terminal domain of human zyxin. This motif is both necessary and sufficient for alpha-actinin binding, whereas a downstream region, which is related in sequence, appears to be dispensable. A synthetic peptide comprising human zyxin residues 21-42 specifically binds to alpha-actinin in solid phase binding assays. In contrast to full-length zyxin, constructs lacking this motif do not interact with alpha-actinin in blot overlays and fail to recruit alpha-actinin in living cells. When zyxin lacking the alpha-actinin binding site is expressed as a fusion protein with green fluorescent protein, association of the recombinant protein with stress fibers is abolished, and targeting to focal adhesions is grossly impaired. Our results suggest a crucial role for the alpha-actinin-zyxin interaction in subcellular zyxin localization and microfilament organization.

Intra-and inter-individual variations in transepidermal water loss on the face: facial locations for bioengineering studies

The volar forearm is the favored location for bioengineering studies. However, transepidermal water loss (TEWL), which is an important indicator of the function of the epidermal barrier, shows regional variations, and for the evaluation of cosmetic formulations, facial skin would be more suitable. In this study, we have compared 10 facial locations with 1 test site on the volar forearm for absolute TEWL values, reproducibility, and correlation. Measurements were performed over 3 consecutive days. The TEWL values of the facial test sites were higher compared to forearm values and did not correlate with the forearm. On the face, there was a good correlation between the values of the right compared to the left side of the face. The sites superior to the nervus supraorbitalis, the medial borders of the musculus masseter, and the center of the chin proved to be locations with relatively stable TEWL values. There was a greater variability at the center of the forehead and at the center of the cheeks. It is recommended that TEWL measurements on facial locations with stable TEWL values are used for the evaluation of cosmetic formulations.

[Rhabdomyolysis and cholestatic hepatitis under treatment with simvastatin and chlorzoxazone]

Acute rhabdomyolysis under treatment with HMG-CoA reductase inhibitors ("statins") is a group-specific if rare side effect. Muscle toxicity of statins can be potentiated by medication influencing their metabolism. Here drug interactions on the level of the microsomal cytochrome P450 enzymes play an important role. We report the first case of marked rhabdomyolysis with cholestatic hepatitis in a 73-year-old woman treated with simvastatin and chlorzoxazone. Withdrawal of the causal medication and conservative therapy with volume substitution and forced diuresis was followed by almost complete resolution of the symptoms with normalisation of the blood tests. Possible mechanisms involved in the drug interactions are discussed. Thorough knowledge of the enzyme systems involved in drug metabolism helps to predict possible adverse drug interactions and prevent toxic effects.

Postmarketing safety information: how useful are spontaneous reports?

From 1995 until June 1998 123 new chemical entities (NCEs) were launched in Switzerland. In this time period 250 reports of adverse reactions (ADRs) involving 56 different NCEs were reported to the Swiss Drug Monitoring Center SANZ directly by physicians within the voluntary spontaneous reporting scheme (SRS). No cases from observational or clinical postmarketing studies were included. Of the reports 88% were suspected to be drug-related and 20% of them were serious. In 64% the ADRs were unlabelled and not notified to the health professionals. Disorders of the central nervous system (CNS) were reported in 32% and cardiovascular disorders in 26% of the unlabelled and serious cases. The non-serious cases accounted for 80% of the reported NCE-ADRs and 60% of them were unlabelled. Skin reactions were reported most frequently (18%), followed by psychic (15%), gastrointestinal (10%), cardiovascular and CNS disorders (8% each). In the labelled non-serious cases gastrointestinal and skin reactions were reported in 25% and 24% respectively. The other system organ classes were involved to a much smaller extent (<8%).

CONCLUSIONS

(1) Spontaneous reports are of great value in optimizing postmarketing safety information. (2) Early reports give rise to a different ADR profile than expected from premarketing safety information. (3) Spontaneous reports have a strong signalling function especially for drugs used by general practitioners. (4) Sensitive signal detection systems are of great value in detecting non-labelled and serious ADRs in an early phase.

[Angioedema induced by ACE inhibitors and angiotensin II-receptor antagonists: analysis of 98 cases]

Angiooedema has been reported as a rare but in most cases serious adverse effect of ACE inhibitors. Recent reports have indicated that angiotensin II-receptor antagonists may also induce angiooedema. As part of the spontaneous reporting scheme in Switzerland the Swiss Drug Monitoring Centre (SANZ) has received reports on 94 cases of ACE inhibitor-induced and 4 cases of angiotension II-receptor antagonist-induced angiooedema. These 98 spontaneously reported cases were analysed in detail. 28 cases were classified as serious and in three patients intubation was even required. In 35% of cases angiooedema was induced within the first week of therapy and in 64% within the first year. In one case the angio-oedema displayed latency of 8 years. Latency of this duration shows that this adverse drug reaction (ADR) may be hard to detect. In 45 of the 98 cases the oedema persisted for more than one day (maximum 2 months), although in some instances the patients continued ACE-inhibitor therapy. In 25 cases the oedema recurred, in one instance as many as 20 times. In rare cases angiooedema may also be induced by angiotensin II-receptor antagonists, although in such instances the course of the oedema was usually milder. In two of the four reported cases angiooedema recurred after switching from an ACE inhibitor to an angiotensin II-receptor antagonists. The four reported cases from Switzerland showed a similar profile when compared with 25 internationally documented cases. Our data indicate that angiooedema is a specific ACE inhibitor ADR. A protracted latency period may be observed and recurrence of oedema is frequent. Angiotensin II-receptor antagonist-induced angiooedema may also occur in rare instances.

Interaction of Listeria monocytogenes with human brain microvascular endothelial cells: InlB-dependent invasion, long-term intracellular growth, and spread from macrophages to endothelial cells

Invasion of endothelial tissues may be crucial in a Listeria monocytogenes infection leading to meningitis and/or encephalitis. Internalization of L. monocytogenes into endothelial cells has been previously demonstrated by using human umbilical vein endothelial cells as a model system. However, during the crossing of the blood-brain barrier, L. monocytogenes most likely encounters brain microvascular endothelial cells which are strikingly different from macrovascular or umbilical vein endothelial cells. In the present study human brain microvascular endothelial cells (HBMEC) were used to study the interaction of L. monocytogenes with endothelial cells, which closely resemble native microvascular endothelial cells of the brain. We show that L. monocytogenes invades HBMEC in an InlB-dependent and wortmannin-insensitive manner. Once within the HBMEC, L. monocytogenes replicates efficiently over a period of at least 18 h, moves intracellularly by inducing actin tail formation, and spreads from cell to cell. Using a green fluorescent protein-expressing L. monocytogenes strain, we present direct evidence that HBMEC are highly resistant to damage by intracellularly growing L. monocytogenes. Infection of HBMEC with L. monocytogenes results in foci of heavily infected, but largely undamaged endothelial cells. Heterologous plaque assays with L. monocytogenes-infected P388D1 macrophages as vectors demonstrate efficient spreading of L. monocytogenes into HBMEC, fibroblasts, hepatocytes, and epithelial cells, and this phenomenon is independent of the inlC gene product.

Patch tests versus use tests in skin irritation risk assessment

In the risk assessment of the ability of a substance or preparation to cause skin irritation, a patch test involving human volunteers is often seen as providing definitive information. However, the skin exposure conditions found in an occluded patch may be far removed from those in a particular use situation, not least for such reasons as the high dose per unit area, the duration of exposure and the maceration of the skin. Whilst these factors may enhance sensitivity in the identification of intrinsic hazard, they may do little to ensure accurate safety evaluation for real use. In this paper, we report data from a series of studies with an unmarketed facial skin cosmetic product. Whilst the product was unexpectedly highly irritating in a standard patch test in 30 volunteers, subsequent use tests, including a 6x daily open application to the elbow for 3 weeks and 2x daily application in a half-face test lasting 3 to 4 weeks and involving 52 volunteers failed to show any evidence of skin irritation. It is concluded that the most meaningful results for skin irritation risk assessment are likely to come from studies which involve relevant patterns of exposure.

Tobacco smoke-induced alterations of cytokeratin expression in the rat nasal activity cavity following chronic inhalation of room-aged sidestream smoke

In a 12-month inhalation study on rats using room-aged sidestream smoke (RASS, 12 microg total particulate matter (TPM)/l) as an experimental surrogate for environmental tobacco smoke (ETS), we investigated differentiation changes, i.e. altered cytokeratin (CK) expression, in the epithelial lining at nasal cavity level 1 (NL1) (anterior portion of nasal cavity), and their correlation with histomorphological changes. In addition to conventional histopathological examination, routine paraffin sections were immunohistologically stained for various rat CK and evaluated. Changes in CK expression were observed in the nonciliated respiratory epithelium of maxilloturbinate, lateral wall, and nasoturbinate: in basal cells, increase of CK14 and CK18 and decrease of CK15; in nonciliated columnar cells, increase of CK15 and CK19. These CK changes had histomorphological correlates, i.e. reserve cell hyperplasia and squamous metaplasia. CK expression changes were also seen at sites without histomorphological changes, e.g. enhanced expression of CK14, CK18 in ciliated cells at the dorsal meatus, and CK15 at the septum. Most of the CK expression changes seen after 1 year of RASS exposure resembled the changes previously seen after 8 days of exposure.

High prevalence of bronchial hyperresponsiveness and asthma in ice hockey players

The prevalence of asthma was studied in a ice hockey team compared with both a floor ball team and the Swiss population. Lung function, bronchial hyperresponsiveness to methacholine, asthma symptoms and exercise-induced asthma were measured in a cross-sectional prospective study. A positive response to the methacholine bronchial provocation test was found in 34.6% of the ice hockey players and 20.8% of the floor ball players (Swiss population 16.4%). The provocative dose causing a 20% fall in the forced expiratory volume in one second (PD20) was significantly lower in ice hockey players than in floor ball players, but there was no significant difference in the dose-response slopes between the two groups. Asthma was diagnosed in 19.2% of the ice hockey players and in 4.2% of the floor ball players (Swiss population 6.8%), whereas exercise-induced asthma was found in 11.5% of the ice hockey players and in 4.2% of the floor ball players. In conclusion, asthma and bronchial hyperresponsiveness seemed to be more common in ice hockey players than in floor ball players and in the Swiss population. Strenuous exercise at lower temperatures may be a risk factor for the higher prevalence of asthma and bronchial hyperresponsiveness, as well as the increased severity of bronchial hyperresponsiveness, particularly in ice hockey players.

Cytokeratin expression patterns in the rat respiratory tract as markers of epithelial differentiation in inhalation toxicology. II. Changes in cytokeratin expression patterns following 8-day exposure to room-aged cigarette sidestream smoke

The expression of specific cytokeratin (CK) polypeptide patterns is a sensitive marker of the cytoskeletal differentiation of epithelial cells. We developed an immunohistochemical method to assess CK expression patterns in the rat respiratory tract using serial paraffin-embedded sections from the nasal cavity, trachea, and lung. In the present study, this method was used to detect exposure-related differences in CK expression patterns in adult Wistar rats following inhalation of room-aged sidestream smoke (11 mg total particulate matter/m3 air, 8 days, 12 hr/day, whole body). In the anterior nasal cavity level 1 (NL1), changes in CK expression patterns were observed in the respiratory epithelium of the lateral wall and the maxilloturbinate (CK14, CK15, and CK18) and in the squamous epithelium of the ventral meatus (CK13). At nasal cavity level 2 (NL2), immediately behind NL1, changes were observed in the olfactory epithelium (CK13, CK14, and CK18) and in the respiratory epithelium of the septum (CK7 and CK19), the lateral wall (CK7 and CK13), and the lateral aspect of the maxilloturbinate (CK14). Changes were also observed in the submucosal glands, nasolacrimal duct, and vomeronasal organ. In the trachea only CK7 expression changed, and in the lung expression of CK7 (bronchioli) and CK8 (bronchus) changed; the expression of other CK polypeptides did not change. The observed changes in CK expression at NL1 correlated with the histomorphological changes, whereas CK expression changes were also seen in the olfactory and respiratory epithelia at NL2 and in the trachea and lung, where no histomorphological changes were seen. These findings indicate that changes in CK expression in respiratory tract epithelial cells are a sensitive marker for cellular stress response.

Cytokeratin expression patterns in the rat respiratory tract as markers of epithelial differentiation in inhalation toxicology. I. Determination of normal cytokeratin expression patterns in nose, larynx, trachea, and lung

Cytokeratin (CK) polypeptides constitute the intermediate filament cytoskeleton of epithelial cells. The patterns of CK expression can be regarded as specific markers for the epithelial differentiation status. Our objective was to map the cell type-specific CK expression patterns at all representative sites of the respiratory tract of untreated rats to use as a base for the detection of inhalation exposure-related differentiation changes. Using routine paraffin-embedded sections and a panel of well-characterized monoclonal antibodies for immunohistochemistry, we obtained CK staining patterns as follows. Nasal cavity: respiratory epithelium CK18, CK19 (basal, ciliated, nonciliated cells), CK14, and/or CK15 (basal and nonciliated cells); olfactory epithelium CK18 (basal, mid, apical zones and Bowman's glands), CK14, and CK15 (basal zone); squamous epithelium of ventral meatus CK14, CK15 (basal and suprabasal cells), CK1, 10/11, and CK13 (suprabasal cells); glands and columnar epithelia of vomeronasal organ and nasolacrimal duct CK7 and CK13 in addition to respiratory epithelial CK pattern. Trachea: similar to nasal respiratory epithelium with pronounced CK15 and additional CK7. Larynx: CK14, CK15 (basal, ciliated, nonciliated cells), CK8, CK18, CK19 (not in basal cells), CK4, and CK13 (cuboidal and squamoid cells of ventral half). Lung: bronchial epithelium CK14 and CK15 (basal cells only); bronchial and alveolar epithelium CK7, CK8, CK18, and CK19; bronchiolar epithelium similar but less CK8 and no CK7; pleural mesothelium CK7, CK8, and CK19. This inventory of complex CK expression patterns provides the basis for investigating test substance-related effects in inhalation toxicology, e.g., cigarette smoke-induced changes.

A randomized comparison of exercise training in patients with normal vs reduced ventricular function

BACKGROUND

Exercise training is recommended after myocardial infarction (MI) or bypass surgery in order to improve exercise tolerance. In some patients, the decrement in exercise capacity secondary to deconditioning and the left ventricular stunning associated with MI or coronary artery bypass graft (CABG) spontaneously improves after the event. However, the impact of the status of the left ventricle on these improvements is unknown.

METHODS

Sixty-seven patients 1 month after MI or CABG were randomized to a training (n=34; age, 59+/-7 years) or a control group (n=33; age, 55+/-6 years). Forty-two patients had an ejection fraction >50% (22 in the training group and 20 in the control group), and 25 patients had an ejection fraction <40% (12 in the exercise group and 13 in the control group). After stabilization for approximately 1 month after the event, patients in the exercise group underwent 8 weeks of twice daily exercise at a residential rehabilitation center, while control patients received usual care. Initially and after 8 weeks, patients in both groups underwent maximal exercise testing with gas exchange and lactate analysis.

RESULTS

Exercise training increased peak oxygen consumption (VO2) only in the reduced ejection fraction group (19.4+/-3.0 to 23.9+/-4.8 mL/kg/min; p<0.05); the exercise group with normal ventricular function did not change significantly. Changes in VO2 at the lactate threshold paralleled those of peak VO2 for both groups. Conversely, control patients with normal ventricular function increased peak VO2 spontaneously (20.8+/-3.9 to 24.8+/-3.5 mL/kg/min; p<0.01), whereas control patients with reduced ventricular function did not improve peak VO2.

CONCLUSION

These data suggest that patients with depressed left ventricular function strongly benefit from rehabilitation, whereas most patients with preserved left ventricular function following MI or CABG tend to improve spontaneously 1 to 3 months after the event.

Guanylin stimulates regulated secretion from human neuroendocrine pancreatic cells

BACKGROUND & AIMS

Gastroenteropancreatic neuroendocrine cells secrete chemical messengers in a calcium-dependent fashion. So far, other second messenger systems involved in regulated secretion have gained little attention. The aim of this study was to characterize guanosine 3',5'-cyclic monophosphate (cGMP)-mediated vesicular secretion in pancreatic neuroendocrine cells.

METHODS

In a human pancreatic cell line, BON, cyclic nucleotide levels and chromogranin A release were monitored with specific immunoassays. Uptake and release of gamma-aminobutyric acid were measured. Intracellular Ca2+ concentration was monitored with fura-2. Guanylyl cyclase C was analyzed by reverse-transcription polymerase chain reaction.

RESULTS

Guanylin increased cGMP concentrations in BON cells via guanylyl cyclase C. Stimulation of the cGMP pathway by guanylin or Escherichia coli heat-stable enterotoxin increased the release of chromogranin A and gamma-aminobutyric acid from BON cells. This effect was mimicked by the cGMP analogue 8-bromo-cGMP.

CONCLUSIONS

Guanylin and STa stimulate the regulated secretion from BON cells via guanylyl cyclase C and cGMP. Our study yields novel information about secretory properties of guanylin, mediated via a signal transduction pathway, increasing cGMP and leading to regulated secretion of neuroendocrine cells.

[Drug-induced discoloration of the teeth and gingiva]

For this article all cases of suspected drug-induced discolouration of teeth and gingiva reported between 1.1.1989 and 31.5.1997 have been collected. As far as documented all discolourations were reversible and represented exclusively undesired but not serious adverse drug effects. In the literature such events are usually not mentioned. Thus, sense and intention of this work is to draw attention to certain adverse effects that are hitherto not well known.

The microtubule depolymerizing drugs nocodazole and colchicine inhibit the uptake of Listeria monocytogenes by P388D1 macrophages

Uptake of Listeria monocytogenes by different mammalian cells like macrophages and epithelial cells is dependent on functional actin filaments and hence susceptible to inhibition by cytochalasin. Here we show that phagocytic uptake of L. monocytogenes by P388D1 macrophages is also highly sensitive to treatment with the microtubule depolymerizing drugs nocodazole and colchicine. This sensitivity is cell type specific and much less pronounced in bone marrow-derived macrophages and Caco-2 epithelial cells. In contrast to nocodazole and colchicine, the microtubule stabilizing drug taxol has no significant effect on the uptake of L. monocytogenes by all three cell types tested.

Lethal pulmonary hypertension in a young woman caused by unrecognized haemangiosis carcinomatosa

A 38-year-old female is described, who was admitted with increasing respiratory distress, cough and visible blood stasis in the jugular veins. The most likely diagnosis in this young women taking oral contraceptives was pulmonary embolism, however, a ventilation-perfusion lung scan was normal. Echocardiography showed a dilated right ventricle and increased systolic pulmonary pressure. Despite administration of oxygen and intravenous heparin the patient died in circulatory collapse before further investigations could be initiated. Post-mortem examination revealed diffuse adenocarcinoma of the stomach (linitis plastica) with metastasis to local lymphnodes, lymphangiosis carcinomatosa of the liver, pancreas and spleen and tumour cell masses within the lumen of small pulmonary arteries leading to variable occlusions of the vessels. Fibrocellular intimal proliferation was found, leading to further obstruction and increased resistance to flow through the pulmonary vascular bed and to subacute cor pulmonale.

[Granulomatous tumor of the flexor tendon sheath as first manifestation of sarcoidosis]

While osseous tumors of the phalanges are more common, soft-tissue manifestations in the hand are uncommon in patients with sarcoidosis. Our patient presented with a large but painless tumor on the palmar aspect of the right index finger limiting finger flexion. Histology of a biopsy specimen was interpreted as a granuloma of sarcoidosis. Further X-ray investigations revealed large bilateral formations in the hila of the lung interpreted as stage I sarcoidosis in an otherwise healthy individual. Tuberculosis and polyarthritis were excluded by standard tests. The tumor was then radically excised, as it was located within the flexor tendon sheath. After uneventful wound healing the patient had regained full function of his finger at six weeks follow up. Interestingly enough, a chest film at that time showed the hilar changes to have decreased as well, which is considered quite typical for this disease.

[Differences in the relative incidence of adverse drug reactions in relation to age? An evaluation of the spontaneous reporting system of SANZ (Swiss Drug Monitoring Center)]

The risk of presenting adverse drug reactions (ADR) is greater for elderly patients. Chronological age is not an independent risk factor for ADRs, but age-dependent factors such as polymedication, multiple diseases and changes in pharmacokinetics and pharmacodynamics seem to be responsible for the risk of developing more adverse drug reactions. We analyzed the ADRs spontaneously reported to the Swiss Drug Monitoring Centre (SANZ) between 1981 and 1995. Age-specific relative incidences of the reported ADRs affecting different organ systems were calculated. For elderly patients we found a decrease in the relative incidence of dermatological ADRs and an increase in neuropsychic and hematological ADRs. The incidence of serious ADRs increased by 8.7% in older patients (> 70 years). The results of this analysis of spontaneous reports were inconsistent with results from epidemiological studies. The possibility and reasons for under-reporting ADRs occurring in elderly patients are discussed.

Host cell signalling during Listeria monocytogenes infection

Macrophages and other mammalian cells respond to infection with Listeria monocytogenes by the transient or persistent activation of host cell signal transduction pathways. In addition, L. monocytogenes infection influences expression of various host cell genes, some of which may hinder or favour bacterial replication. The observed host cell responses vary with the different subcellular locations inhabited by L. monocytogenes during its intracellular life cycle.