MAPK activated kinase 2 inhibition shifts the chemokine signature in arthritis synovial fluid mononuclear cells from CXCR3 to CXCR2

BACKGROUND

The development of novel treatment strategies of immune-mediated inflammatory arthritis (IMIA) is still a clinical unmet need. The mitogen-activated protein kinase (MAPK) pathway is activated by environmental stressors, growth factors and inflammatory cytokines. However, the inhibition of central MAPK proteins has so far had undesirable side effects. The MAPK-activated protein kinase 2 (MK2) is a downstream mediator in the MAPK signaling pathway.

OBJECTIVES

The objective of this study was to explore the effects of a small molecule inhibiting MK2 on synovial fluid mononuclear cells from patients with IMIA.

METHODS

Synovial fluid mononuclear cells (SFMCs) were obtained from a study population consisting of patients with active rheumatoid arthritis (RA), peripheral spondyloarthritis (SpA) or psoriatic arthritis (PsA) with at least one swollen joint (for obtaining synovial fluid) (n = 11). SFMCs were cultured for 48 h with and without the MK2 inhibitor CC0786512 at 1000 nM, 333 nM and 111 nMand cell free supernatants were harvested and frozen before they were analyzed by the Olink proseek multiplex interferon panel.

RESULTS

In SFMCs cultured for 48 h, the MK2 inhibitor decreased the production of chemokine (C-X-C motif) ligand 9 (CXCL9) (P < 0.001), CXCL10 (P < 0.01), hepatocyte growth factor (HGF) (P < 0.01), CXCL11 (P < 0.01), tumor necrosisfactor-like weak inducer of apoptosis (TWEAK) (P < 0.05), and interleukin 12B (IL-12B) (P < 0.05) and increased the production of CXCL5 (P < 0.0001), CXCL1 (P < 0.0001), CXCL6 (P < 0.001), transforming growthfactoralpha (TGFα) (P = 0.01), monocyte-chemotactic protein 3 (MCP-3) (P < 0.01), latency-associated peptide (LAP) TGFβ (P < 0.05) dose-dependently.

CONCLUSIONS

This study reveals the downstream effects of MK2 inhibition on the secretory profile of SFMCs. Specifically, C-X-C motif chemokine receptors 3 (CXCR3) chemokines were decreased and CXCR2 chemokines were increased. This shift in the chemokine milieu may be one of the mechanisms behind the anti-inflammatory effects of MK2 inhibitors.

Comparison of immune checkpoint inhibitor-induced arthritis and reactive arthritis to inform therapeutic strategy

INTRODUCTION

Immune checkpoint inhibitor-induced inflammatory arthritis (ICI-IA) is a relatively new disease entity caused by ICI agents during cancer therapy. Reactive arthritis (ReA) is a well-known disease entity caused by urogenital or gastrointestinal bacterial infection or pneumonia. In this sense, ICI-IA and ReA are both defined by a reaction to a well-specified causal event. As a result, comparing these diseases may help to determine therapeutic strategies.

METHODS

We compared ICI-IA and ReA with special focus on pharmacological management. Specifically regarding treatment, we conducted a literature search of studies published in the PubMed database. Inclusion criteria were studies on treatment with non-steroidal anti-inflammatory drugs (NSAIDs), glucocorticoids (GC), or disease modifying antirheumatic drugs (DMARDs) in ICI-IA or ReA. During systematic selection, 21 studies evaluating ICI-IA and 14 studies evaluating ReA were included.

RESULTS

In ICI-IA, prospective and retrospective studies have shown effects of non-steroidal anti-inflammatory drugs (NSAIDs), glucocorticoid (GC), sulfasalazine (SSZ), methotrexate (MTX), hydroxychloroquine (HCQ) and TNFi. In ReA, retrospective studies evaluated NSAIDs and GC. A randomized controlled trial reported the effect of SSZ, and a retrospective study reported the effect of MTX and SSZ in combination with tumor necrosis factor alpha inhibition (TNFi). For both entities, small case reports show treatment effects of interleukin 6 receptor inhibition (IL-6Ri).

DISCUSSION

This literature review identified both similarities and differences regarding the pathogenesis and clinical features of ReA and ICI-IA. Studies on treatment reported effectiveness of NSAIDs, GC, MTX, SSZ and TNFi in both diseases. Further, small case reports showed effects of IL-6Ri.

Tumor necrosis factor alpha neutralization attenuates immune checkpoint inhibitor-induced activation of intermediate monocytes in synovial fluid mononuclear cells from patients with inflammatory arthritis

Objective

During treatment with immune checkpoint inhibitors (ICI) such as the anti-PD-1 antibody pembrolizumab, half of patients with pre-existing inflammatory arthritis experience disease flares. The underlying immunological mechanisms have not been characterized. Here, we investigate the effect of pembrolizumab on cells involved in inflammation and destruction in the synovial joint and how immunosuppressive treatments affect the pembrolizumab-induced immune reactions.

Methods

We included synovial fluid mononuclear cells (SFMCs, n = 28) and peripheral blood mononuclear cells (PBMCs, n = 6) from patients with rheumatoid arthritis and peripheral spondyloarthritis and PBMCs from healthy controls (n = 6). Fibroblast-like synovial cells (FLSs) were grown from SFMCs. The in vitro effect of pembrolizumab was tested in SFMCs cultured for 48 h, FLS-PBMC co-cultures and in SFMCs cultured for 21 days (inflammatory osteoclastogenesis). Cells and supernatants were analyzed by ELISA, flow cytometry, and pro-inflammatory multiplex assay. Finally, the effect of the disease-modifying anti-rheumatic drugs (DMARDs) adalimumab (TNFα inhibitor), tocilizumab (IL-6R inhibitor), tofacitinib (JAK1/JAK3 inhibitor), and baricitinib (JAK1/JAK2 inhibitor) on pembrolizumab-induced immune reactions was tested.

Results

Pembrolizumab significantly increased monocyte chemoattractant protein-1 (MCP-1) production by arthritis SFMCs (P = 0.0031) but not by PBMCs from patients or healthy controls (P = 0.77 and P = 0.43). Pembrolizumab did not alter MMP-3 production in FLS-PBMC co-cultures (P = 0.76) or TRAP secretion in the inflammatory osteoclastogenesis model (P = 0.28). In SFMCs, pembrolizumab further increased the production of TNFα (P = 0.0110), IFNγ (P = 0.0125), IL-12p70 (P = 0.0014), IL-10 (P = 0.0100), IL-13 (P = 0.0044), IL-2 (P = 0.0066), and IL-4 (P = 0.0008) but did not change the production of IL-6 (P = 0.1938) and IL-1 (P = 0.1022). The SFMCs treated with pembrolizumab showed an increased frequency of intermediate monocytes (P = 0.044), and the MCP-1 production increased only within the intermediate monocyte subset (P = 0.028). Lastly, adalimumab, baricitinib, and tofacitinib treatment were able to attenuate the pembrolizumab-induced MCP-1 production (P = 0.0004, P = 0.033, and P = 0.025, respectively), while this was not seen with tocilizumab treatment (P = 0.75).

Conclusion

Pembrolizumab specifically activated intermediate monocytes and induced the production of several cytokines including TNFα but not IL-6. These findings indicate that flares in patients with pre-existing inflammatory arthritis involve monocyte activation and could be managed with TNFα neutralization.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-022-02737-6.

The effects of B cell depletion on immune related adverse events associated with immune checkpoint inhibition

This letter describes the potential effect of B cell depletion on immune related adverse events associated with immune checkpoint inhibition. B cell depleting agents such as rituximab reduce B cell to plasma cell differentiation and antibody production. This treatment strategy is used in several immune mediated inflammatory diseases such as rheumatoid arthritis and small vessel vasculitis. The immune related adverse events associated with immune checkpoint inhibition resemble immune mediated inflammatory diseases. Here, we report a lower incidence of hypothyroidism in a trial of combined B cell depletion and immune checkpoint inhibitor treatment compared with studies of immune checkpoint inhibitor monotherapy. This letter aims to increase awareness of the immune related adverse events associated with immune checkpoint inhibition in future clinical trials of immune checkpoint inhibition together with B cell depletion (primarily trials of B cell lymphomas). Hopefully, observations from these clinical trials can guide future treatment strategies to treat or prevent immune related adverse events associated with immune checkpoint inhibition.

Phonon Decoherence of Quantum Dots in Photonic Structures: Broadening of the Zero-Phonon Line and the Role of Dimensionality

We develop a general microscopic theory describing the phonon decoherence of quantum dots and indistinguishability of the emitted photons in photonic structures. The coherence is found to depend fundamentally on the dimensionality of the structure resulting in vastly different performance for quantum dots embedded in a nanocavity (0D), waveguide (1D), slab (2D), or bulk medium (3D). In bulk, we find a striking temperature dependence of the dephasing rate scaling as T^{11} implying that phonons are effectively "frozen out" for T≲4  K. The phonon density of states is strongly modified in 1D and 2D structures leading to a linear temperature scaling for the dephasing strength. The resulting impact on the photon indistinguishability can be important even at sub-Kelvin temperatures. Our findings provide a comprehensive understanding of the fundamental limits to photon indistinguishability in photonic structures.

Dissipative quantum error correction and application to quantum sensing with trapped ions

Quantum-enhanced measurements hold the promise to improve high-precision sensing ranging from the definition of time standards to the determination of fundamental constants of nature. However, quantum sensors lose their sensitivity in the presence of noise. To protect them, the use of quantum error-correcting codes has been proposed. Trapped ions are an excellent technological platform for both quantum sensing and quantum error correction. Here we present a quantum error correction scheme that harnesses dissipation to stabilize a trapped-ion qubit. In our approach, always-on couplings to an engineered environment protect the qubit against spin-flips or phase-flips. Our dissipative error correction scheme operates in a continuous manner without the need to perform measurements or feedback operations. We show that the resulting enhanced coherence time translates into a significantly enhanced precision for quantum measurements. Our work constitutes a stepping stone towards the paradigm of self-correcting quantum information processing.

Quantum error correction plays a key role in quantum information and metrology, but generally requires complex gates and measurements sequences. Here, the authors use trapped ions to implement a scheme in which always-on coupling to an engineered environment protects the qubit against errors.

Preparation of Entangled States through Hilbert Space Engineering

We apply laser fields to trapped atomic ions to constrain the quantum dynamics from a simultaneously applied global microwave field to an initial product state and a target entangled state. This approach comes under what has become known in the literature as "quantum Zeno dynamics" and we use it to prepare entangled states of two and three ions. With two trapped ^{9}Be^{+} ions, we obtain Bell state fidelities up to 0.990_{-5}^{+2}; with three ions, a W-state fidelity of 0.910_{-7}^{+4} is obtained. Compared to other methods of producing entanglement in trapped ions, this procedure can be relatively insensitive to certain imperfections such as fluctuations in laser intensity.

Coherent Backscattering of Light Off One-Dimensional Atomic Strings

We present the first experimental realization of coherent Bragg scattering off a one-dimensional system-two strings of atoms strongly coupled to a single photonic mode-realized by trapping atoms in the evanescent field of a tapered optical fiber, which also guides the probe light. We report nearly 12% power reflection from strings containing only about 1000 cesium atoms, an enhancement of 2 orders of magnitude compared to reflection from randomly positioned atoms. This result paves the road towards collective strong coupling in 1D atom-photon systems. Our approach also allows for a straightforward fiber connection between several distant 1D atomic crystals.

Scalable photonic network architecture based on motional averaging in room temperature gas

Quantum interfaces between photons and atomic ensembles have emerged as powerful tools for quantum technologies. Efficient storage and retrieval of single photons requires long-lived collective atomic states, which is typically achieved with immobilized atoms. Thermal atomic vapours, which present a simple and scalable resource, have only been used for continuous variable processing or for discrete variable processing on short timescales where atomic motion is negligible. Here we develop a theory based on motional averaging to enable room temperature discrete variable quantum memories and coherent single-photon sources. We demonstrate the feasibility of this approach to scalable quantum memories with a proof-of-principle experiment with room temperature atoms contained in microcells with spin-protecting coating, placed inside an optical cavity. The experimental conditions correspond to a few photons per pulse and a long coherence time of the forward scattered photons is demonstrated, which is the essential feature of the motional averaging.

Heralded quantum gates with integrated error detection in optical cavities

We propose and analyze heralded quantum gates between qubits in optical cavities. They employ an auxiliary qubit to report if a successful gate occurred. In this manner, the errors, which would have corrupted a deterministic gate, are converted into a nonunity probability of success: once successful, the gate has a much higher fidelity than a similar deterministic gate. Specifically, we describe that a heralded, near-deterministic controlled phase gate (CZ gate) with the conditional error arbitrarily close to zero and the success probability that approaches unity as the cooperativity of the system, C, becomes large. Furthermore, we describe an extension to near-deterministic N-qubit Toffoli gate with a favorable error scaling. These gates can be directly employed in quantum repeater networks to facilitate near-ideal entanglement swapping, thus greatly speeding up the entanglement distribution.

Probing electric and magnetic vacuum fluctuations with quantum dots

The electromagnetic-vacuum-field fluctuations are intimately linked to the process of spontaneous emission of light. Atomic emitters cannot probe electric- and magnetic-field fluctuations simultaneously because electric and magnetic transitions correspond to different selection rules. In this Letter we show that semiconductor quantum dots are fundamentally different and are capable of mediating electric-dipole, magnetic-dipole, and electric-quadrupole transitions on a single electronic resonance. As a consequence, quantum dots can probe electric and magnetic fields simultaneously and can thus be applied for sensing the electromagnetic environment of complex photonic nanostructures. Our study opens the prospect of interfacing quantum dots with optical metamaterials for tailoring the electric and magnetic light-matter interaction at the single-emitter level.

Heisenberg-limited atom clocks based on entangled qubits

We present a quantum-enhanced atomic clock protocol based on groups of sequentially larger Greenberger-Horne-Zeilinger (GHZ) states that achieves the best clock stability allowed by quantum theory up to a logarithmic correction. Importantly the protocol is designed to work under realistic conditions where the drift of the phase of the laser interrogating the atoms is the main source of decoherence. The simultaneous interrogation of the laser phase with a cascade of GHZ states realizes an incoherent version of the phase estimation algorithm that enables Heisenberg-limited operation while extending the coherent interrogation time beyond the laser noise limit. We compare and merge the new protocol with existing state of the art interrogation schemes, and identify the precise conditions under which entanglement provides an advantage for clock stabilization: it allows a significant gain in the stability for short averaging time.

Efficient atomic clocks operated with several atomic ensembles

Atomic clocks are typically operated by locking a local oscillator (LO) to a single atomic ensemble. In this Letter, we propose a scheme where the LO is locked to several atomic ensembles instead of one. This results in an exponential improvement compared to the conventional method and provides a stability of the clock scaling as (αN)(-m/2) with N being the number of atoms in each of the m ensembles and α a constant depending on the protocol being used to lock the LO.

Near-Heisenberg-limited atomic clocks in the presence of decoherence

The ultimate stability of atomic clocks is limited by the quantum noise of the atoms. To reduce this noise it has been suggested to use entangled atomic ensembles with reduced atomic noise. Potentially this can push the stability all the way to the limit allowed by the Heisenberg uncertainty relation, which is denoted the Heisenberg limit. In practice, however, entangled states are often more prone to decoherence, which may prevent reaching this performance. Here we present an adaptive measurement protocol that in the presence of a realistic source of decoherence enables us to get near-Heisenberg-limited stability of atomic clocks using entangled atoms. The protocol may thus realize the full potential of entanglement for quantum metrology despite the detrimental influence of decoherence.

Laser cooling and optical detection of excitations in a LC electrical circuit

We explore a method for laser cooling and optical detection of excitations in a room temperature LC electrical circuit. Our approach uses a nanomechanical oscillator as a transducer between optical and electronic excitations. An experimentally feasible system with the oscillator capacitively coupled to the LC and at the same time interacting with light via an optomechanical force is shown to provide strong electromechanical coupling. Conditions for improved sensitivity and quantum limited readout of electrical signals with such an "optical loud speaker" are outlined.

Environment-assisted precision measurement

We describe a method to enhance the sensitivity of precision measurements that takes advantage of the environment of a quantum sensor to amplify the response of the sensor to weak external perturbations. An individual qubit is used to sense the dynamics of surrounding ancillary qubits, which are in turn affected by the external field to be measured. The resulting sensitivity enhancement is determined by the number of ancillas that are coupled strongly to the sensor qubit; it does not depend on the exact values of the coupling strengths and is resilient to many forms of decoherence. The method achieves nearly Heisenberg-limited precision measurement, using a novel class of entangled states. We discuss specific applications to improve clock sensitivity using trapped ions and magnetic sensing based on electronic spins in diamond.

Dissipative preparation of entanglement in optical cavities

We propose a novel scheme for the preparation of a maximally entangled state of two atoms in an optical cavity. Starting from an arbitrary initial state, a singlet state is prepared as the unique fixed point of a dissipative quantum dynamical process. In our scheme, cavity decay is no longer undesirable, but plays an integral part in the dynamics. As a result, we get a qualitative improvement in the scaling of the fidelity with the cavity parameters. Our analysis indicates that dissipative state preparation is more than just a new conceptual approach, but can allow for significant improvement as compared to preparation protocols based on coherent unitary dynamics.

Optomechanical transducers for long-distance quantum communication

We describe a new scheme to interconvert stationary and photonic qubits which is based on indirect qubit-light interactions mediated by a mechanical resonator. This approach does not rely on the specific optical response of the qubit and thereby enables optical quantum interfaces for a wide range of solid state spin and charge based systems. We discuss the implementation of state transfer protocols between distant nodes of a quantum network and show that high transfer fidelities can be achieved under realistic experimental conditions.

Coupling nitrogen-vacancy centers in diamond to superconducting flux qubits

We propose a method to achieve coherent coupling between nitrogen-vacancy (NV) centers in diamond and superconducting (SC) flux qubits. The resulting coupling can be used to create a coherent interaction between the spin states of distant NV centers mediated by the flux qubit. Furthermore, the magnetic coupling can be used to achieve a coherent transfer of quantum information between the flux qubit and an ensemble of NV centers. This enables a long-term memory for a SC quantum processor and possibly an interface between SC qubits and light.

Hybrid long-distance entanglement distribution protocol

We propose a hybrid (continuous-discrete variable) quantum repeater protocol for long-distance entanglement distribution. Starting from states created by single-photon detection, we show how entangled coherent state superpositions can be generated by means of homodyne detection. We show that near-deterministic entanglement swapping with such states is possible using only linear optics and homodyne detectors, and we evaluate the performance of our protocol combining these elements.

Spin squeezing of atomic ensembles via nuclear-electronic spin entanglement

We demonstrate spin squeezing in a room temperature ensemble of approximately 10(12) cesium atoms using their internal structure, where the necessary entanglement is created between nuclear and electronic spins of each individual atom. This state provides improvement in measurement sensitivity beyond the standard quantum limit for quantum memory experiments and applications in quantum metrology and is thus a complementary alternative to spin squeezing obtained via interatom entanglement. Squeezing of the collective spin is verified by quantum state tomography.

Quantum optics with surface plasmons

We describe a technique that enables strong, coherent coupling between individual optical emitters and guided plasmon excitations in conducting nanostructures at optical frequencies. We show that under realistic conditions optical emission can be almost entirely directed into the plasmon modes. As an example, we describe an application of this technique involving efficient generation of single photons on demand, in which the plasmon is efficiently outcoupled to a dielectric waveguide.

Fault-tolerant quantum communication based on solid-state photon emitters

We describe a novel protocol for a quantum repeater that enables long-distance quantum communication through realistic, lossy photonic channels. Contrary to previous proposals, our protocol incorporates active purification of arbitrary errors at each step of the protocol using only two qubits at each repeater station. Because of these minimal physical requirements, the present protocol can be realized in simple physical systems such as solid-state single photon emitters. As an example, we show how nitrogen-vacancy color centers in diamond can be used to implement the protocol, using the nuclear and electronic spin to form the two qubits.

Stability of atomic clocks based on entangled atoms

We analyze the effect of realistic noise sources for an atomic clock consisting of a local oscillator that is actively locked to a spin-squeezed (entangled) ensemble of N atoms. We show that the use of entangled states can lead to an improvement of the long-term stability of the clock when the measurement is limited by decoherence associated with instability of the local oscillator combined with fluctuations in the atomic ensemble's Bloch vector. Atomic states with a moderate degree of entanglement yield the maximal clock stability, resulting in an improvement that scales as N(1/6) compared to the atomic shot noise level.

Entanglement and extreme spin squeezing

For any mean value of a Cartesian component of a spin vector we identify the smallest possible uncertainty in any of the orthogonal components. The corresponding states are optimal for spectroscopy and atomic clocks. We show that the results for different spin J can be used to identify entanglement and to quantify the depth of entanglement in systems with many particles. With the procedure developed in this Letter, collective spin measurements on an ensemble of particles can be used as an experimental proof of multiparticle entanglement.

[Streptococcus bovis as the cause of combined endocarditis of the aortic, mitral and tricuspid valves]

A case of combined endocarditis of the aortic-, mitral- and tricuspid valves in an otherwise healthy cattle farmer is described. The infective agent was Streptococcus bovis. The relation between S. bovis infection and endocarditis is discussed.

[Why do patients change physicians?]

The purpose of this investigation was to describe why patients change their general practitioners (GP) by the means of questionnaires. Questionnaires were given 357 patients who had changed GPs in 1990 and 206 (58%) returned the questionnaire. The most common reasons were dissatisfaction with the quality of the service provided, too little time allowed or lack of communication between patient and doctor. Women accounted for approximately 75% of the total number and preferred female GPs, whereas men who changed doctors probably did so because they wanted to have the same GP as their families. The frequency of change was about 1% and most of the patients had stuck to the same GP for several years before changing.

Personality characteristics and epilepsy

Patients with a long history of temporal lobe epilepsy or primary generalized epilepsy entered a questionnaire study of personality characteristics, based on a modification of the Bear-Fedio inventory for temporal lobe behavioural syndrome. Psoriasis patients and healthy volunteers served as controls. Four clinical meaningful dimensions of included personality traits were identified: ixoide, ideational, obsessive-compulsive and affective features. Analyses based on the Rasch model approved of all dimensions except for affective features. The epilepsy group obtained the highest scores on all 3 dimensions, healthy volunteers the lowest, while the psoriasis group repeatedly held an intermediate position in all sets of assessment (subjects, interviewers and relatives). A logistic regression analysis showed ixoide features being most important when the entire epilepsy group was compared with other study groups, while the dimension ideational features was significant when the temporal lobe epilepsy group was entered as target group and opposed to primary generalized epilepsy. The intermediate position of the psoriasis group, however, suggests that in addition to the presence of a cerebral dysfunction in the epilepsy group, the mere presence of a chronic disorder with potential social stigmatization influences personality.

[Addiction to drugs and alcohol among physicians and nurses]

A retrospective investigation based on case reports was undertaken concerning abuse of alcohol and drugs among medical staff, 44 doctors and 23 nurses, who were treated in the Department of Psychiatry, Rigshospitalet during the period 1970-1982, all of whom received treatment for more than six months. By the end of 1987, a marked excessive mortality was found and this was greatest among doctors among whom 50% had died with an average age of 45.5 years. Factors which were found to be of significance for the prognosis for duration of survival in this selected material were 1) duration of the abuse of medicine, 2) presence of mixed alcohol and drug abuse and 3) previous suicidal attempts.

Cerebral blood flow during delirium tremens and related clinical states studied with xenon-133 inhalation tomography

The regional cerebral blood flow of 12 patients with severe alcohol withdrawal reactions (delirium tremens or impending delirium tremens) was measured during the acute state before treatment and after recovery. Greater cerebral blood flow was significantly correlated with visual hallucinations and agitation during the acute withdrawal reaction. The results suggest that delirium tremens and related clinical states represent a type of acute brain syndrome mainly characterized by CNS hyperexcitability.

Ego functions in epilepsy

Two groups of epilepsy patients (28 patients with temporal lobe epilepsy and 15 patients with primary generalized epilepsy) entered a study of personality traits related to epilepsy, based on a modification of Bellak's semistructured interview for assessment of ego strength. Two groups of subjects served as controls: 15 patients with a non-neurological but relapsing disorder, psoriasis, and 15 healthy volunteers. Compared with the group of healthy volunteers, a decreased adaptive level of ego functioning was found in the epilepsy groups, regardless of seizure types and EEG findings, and, to a lesser extent, compared with the psoriasis group. Areas of ego functioning most affected were "reality testing", "cognitive functioning", "integrative functioning" and "regulation and control of drives". Patients with more than one type of seizure were the most affected, as were patients who were younger than 15 years when the disease began. The number of anticonvulsants administered did not influence the results. No difference on adaptive level of ego functioning was found between the group with primary generalized epilepsy and the group with temporal lobe epilepsy. Similarly, the temporal lobe epilepsy group with predominantly right-sided and left-sided EEG changes, respectively, showed similar adaptive levels of ego functioning.

5-HT and 5-HIAA in cerebrospinal fluid in depression

CSF 5-HT and 5-HIAA were measured in endogenously depressed patients (ICD-9) (n = 23) and controls (n = 11). Distribution of sex, age and body height was similar in the two groups. Non-parametric statistics were used. In depressed patients CSF 5-HT concentrations were found to be higher (P less than or equal to 0.01) than in controls. A further classification of the depressed patients by the Newcastle Scale showed that the highest values were found in the endogenous group compared to the non-endogenous group (P less than or equal to 0.02). CSF 5-HIAA was found to be equal in the two groups, even when pairs matched for height were compared. No relation between clinical recovery due to drug treatment and changes in CSF 5-HT was seen. Our data support a possible involvement of 5-HT in the biology of depression, but the anatomical and functional levels of a serotonin derangement are still unknown.

Femoxetine and cimetidine: interaction in healthy volunteers

The possibility of a pharmacokinetic interaction between femoxetine and cimetidine has been evaluated in 8 healthy volunteers. Two volunteers received single doses of femoxetine, and 6 were given multiple doses of femoxetine for 7 days with and without concurrent cimetidine. No influence of cimetidine was observed on the kinetics of single doses of femoxetine, but after multiple doses the plasma concentration of femoxetine was significantly increased. Similarly, the AUC at steady state tended to be increased, but not to a significant extent. Concurrent cimetidine did not cause a reduction in the AUC of the active desmethyl metabolite. It is recommended that femoxetine is given in reduced doses (e.g. 400 mg) when administered with cimetidine.