Cannabinoid hyperemesis syndrome, a treatment discussion

Introduction

Cannabinoid hyperemesis syndrome (CHS), is characterized by recurrent episodes of severe nausea and intractable vomiting, preceded by chronic use of cannabis. A pathognomonic characteristic is compulsive bathing in hot water. The resolution of the problem occurs when cannabis use is stopped. However, patients are often reluctant to discontinue cannabis. Treatment with anti-emetic medication is ineffective. Case series suggested haloperidol as a potential treatment. Other antipsychotics as olanzapine has been used as anti-emetic treatment in chemotherapy.

Objectives

To describe three cases of patients with CHS whom showed a successful response to olanzapine, even when, haloperidol had failed.

Aims

To present an alternative treatment for CHS which can offer benefits over haloperidol.

Methods

We present three cases of patients who suffered from CHS and were admitted to emergency department. All patients were treated with olanzapine after conventional anti-hemetic treatment failure. One patient was also unsuccessfully treated with haloperidol.

Results

All three patients showed a good response to olanzapine treatment. Different presentations were effective: velotab and intramuscular. Their nausea, vomits and agitation were ameliorated. They could be discharge after maintained remission of symptoms.

Conclusions

Olanzapine should be considered as an adequate treatment for CHS. Its suitable receptorial profile, its availability in different routes of administration and its side effects profile could offer some benefits over haloperidol.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Clozapine induced diarrhea

Introduction

Clozapine (CZP) is the only antipsychotic approved for resistant schizophrenia 1. Due to its side effects, CZP is not the first therapeutic option in a psychotic episode. Its anticholinergic effects often cause constipation, however, diarrhea have also been described in literature.

Objectives

We describe a patient with two episodes of severe diarrhea after clozapine initiation, which lead to CZP discontinuation.

Aims

Discuss about the differential diagnosis of diarrhea in CZP patients and the needing of a further studies for clarify the more appropriate management in CZP induced diarrhea.

Methods

We present a case report of a 46 years man diagnosed with schizoaffective disorder who presented two episodes of severe diarrhea with fever, which forced his transfer to internal medicine and UCI after CZP initiation.

Results

At the first episode analytical, radiological and histological findings led to Crohn's disease diagnosis, which required budesonide and mesalazine treatment. In the second episode, the digestive team concluded that the episode was due to clozapine toxicity despite the controversial findings (clostridium toxin and Crohn's compatible biopsies)

Conclusions

Diarrhea caused by CZP has been controversial in the literature. However due to the severity of digestive episodes and the paucity of alternative treatments further studies for a better understanding of its physiopathology are warranted.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Polydipsia and intermittent hyponatremia

Introduction

Hyponatraemia occurs in 4% of schizophrenic patients. Dilutional hyponatraemia, due to inappropriate retention of water and excretion of sodium, occurs with different psychotropic medications and could lead to hippocampal dysfunction. This complication is usually asymptomatic but can cause severe problems, as lethargy and confusion, difficult to diagnose in mentally ill patients.

Objectives

To describe a case of a patient with psychotropic poli-therapy, admitted three times due to hyponatremia and the pharmacological changes that improved his condition.

Aims

To broadcast the intermittent hyponatraemia and polydipsia (PIP), a not rare condition, suffered by treated schizophrenic patients and discuss its physiopathology and treatment thorough a case report.

Methods

A 56-year schizophrenic male was admitted for presenting disorganized behavior, agitation, auditory hallucinations, disorientation, ataxia, vomits and urinary retention. He was on clomipramine, haloperidol and clotiapine (recently added), quetiapine, fluphenazine and clonazepam. After water restriction his symptoms improved and he was discharged. Twenty-five days later, he was readmitted for presenting the same symptoms and after water restriction, he was discharged. Five days later, he was again admitted and transferred to the psychiatric ward.

Results

Haloperidol, fluphenazine and clomipramine were replaced by clozapine. These changes lead him to normalize the hypoosmolality and reduce his water-voracity. Endocrinology team did not label this episode of SIADH due to its borderline blood and urine parameters.

Conclusions

Hyponatremia is frequent in schizophrenic patients and may have severe consequences. Therefore, a prompt recognition and treatment is warranted.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

High spatial resolution, low-noise Brillouin dynamic gratings reflectometry based on digital pulse compression

Digital pulse compression was used to enhance the performance of optical time-domain reflectometry, employing Brillouin dynamic gratings (BDGs) in polarization-maintaining fibers. The fundamental and unique issues in BDG field-reflection are addressed, and rules for proper selection of the coding and detection techniques are formulated. While coding in BDG applications generally requires coherent processing of the reflection, conditions are established for use of direct detection. A 256-bit Golay complementary unipolar probe code is used to demonstrate an eightfold signal-to-noise ratio enhancement in the measurement of the Brillouin gain spectrum (BGS), with a spatial resolution of 2 cm and a full-BGS acquisition rate of 133⅓ kHz, resulting in an equivalent reduction in the estimation error of small Brillouin frequency shifts.

Enhanced spontaneous backscattering in Brillouin dynamic gratings

Spontaneous Brillouin backscattering, which accompanies the operation of Brillouin dynamic gratings (BDGs) setups, is investigated both theoretically and experimentally. It is shown that this noisy emission, which cannot be separated from the signal of interest, contains not only the probe spontaneous Brillouin backscattering but also a significant contribution from the spontaneous/stimulated acoustic field, originating from the high-frequency writing pump. In the absence of the low-frequency writing pump and for a strong enough high-frequency writing pump, the observed Stokes noise can exhibit an average backscattered power much higher than that from the probe alone.

Direct experimental limit on neutron-mirror-neutron oscillations

In case a mirror world with a copy of our ordinary particle spectrum would exist, the neutron n and its degenerate partner, the mirror neutron n', could potentially mix and undergo nn' oscillations. The interaction of an ordinary magnetic field with the ordinary neutron would lift the degeneracy between the mirror partners, diminish the n' amplitude in the n wave function and, thus, suppress its observability. We report an experimental comparison of ultracold neutron storage in a trap with and without superimposed magnetic field. No influence of the magnetic field is found and, assuming negligible mirror magnetic fields, a limit on the oscillation time taunn' > 103 s (95% C.L.) is derived.

Persistence of spectral variations in DGD statistics

We observe distinct variations between the DGD temporal statistics for different channels in a field installed system. This phenomenon is confirmed with statistical analysis, using a model in which DGD dynamics are due only to a finite number of active points along the link.

Quantitative molecular monitoring of residual tumor cells in chronic lymphocytic leukemia

New therapeutic approaches for the treatment of B-cell chronic lymphocytic leukemia (B-CLL) can induce remarkable responses. Molecular remissions have been observed occasionally after high-dose chemotherapy. Thus, new improved techniques to monitor residual tumor cells on a molecular basis in CLL are warranted. For this purpose, a real-time quantitative allele-specific oligonucleotide polymerase chain reaction (ASO-PCR) for patients with B-CLL was designed. In the present study, the PCR assay was standardized with identical cycling parameters as well as primer, probe, and MgCl(2) concentration for each patient. Ten patients were monitored with DNA samples obtained at 52 time points (median: 5.2 per patient). The median follow-up per patient was 11.4 months. Nine of ten patients had PCR-detectable residual tumor cells in the peripheral blood after therapy. One patient became PCR negative with a combination of fludarabine and rituximab after the end of treatment. The MRD levels in patients with detectable disease ranged from 0.002% to 10.1% after therapy. We conclude that real-time quantitative ASO-PCR can be utilized for quantitative molecular monitoring of minimal residual disease (MRD) in B-CLL patients in complete remission (CR), that new effective treatment approaches such as combined chemo/immunotherapy can render CLL patients PCR negative, and that different MRD levels in PCR-positive patients were observed warranting further investigation into possible correlation with clinical outcome.

Statistical determination of the length dependence of high-order polarization mode dispersion

We describe a method of characterizing high-order polarization mode dispersion (PMD). Using a new expansion to approximate the Jones matrix of a polarization-dispersive medium, we study the length dependence of high-order PMD to the fourth order. A simple rule for the asymptotic behavior of PMD for short and long fibers is found. It is also shown that, in long fibers (~1000 km), at 40 Gbits/s the third- and fourth-order PMD may become comparable to the second-order PMD.

Highly sensitive dynamic strain measurements by locking lasers to fiber Bragg gratings

A novel, sensitive, simple, and robust strain interrogation technique is analyzed and experimentally tested. By locking a laser wavelength to the midreflection wavelength of a standard fiber Bragg grating and measuring the error signal, we achieve high dynamic strain sensitivity of 45 picostrain/ radicalHz rms at 3 kHz, where the dominant noise in the experiment is the laser frequency noise.

Position-invariant, rotation-invariant, and scale-invariant process for binary image recognition

A novel recognition process is presented that is invariant under position, rotation, and scale changes. The recognition process is based on the Fang-Häusler transform [Appl. Opt. 29, 704 (1990)] and is applied to the autoconvolved image, rather than to the image itself. This makes the recognition process sensitive not only to the image histogram but also to its detailed pattern, resulting in a more reliable process that is also applicable to binary images. The proposed recognition process is demonstrated, by use of a fast algorithm, on several types of binary images with a real transform kernel, which contains amplitude, as well as phase, information. Good recognition is achieved for both synthetic and scanned images. In addition, it is shown that the Fang-Hausler transform is also invariant under a general affine transformation of the spatial coordinates.

Digital signal processing for an open-loop fiber-optic gyroscope

Open-loop fiber-optic gyroscopes (FOG's) are generally less stable than closed-loop FOG's, yet they offer simpler implementation. We propose a modification of the harmonic division algorithm for an open-loop FOG, which is more stable and also simpler for implementation than the original one. It is shown that when the analog signal is properly sampled and quantized, the performance of our algorithm reaches that of closed-loop FOG's. Our algorithm may be implemented by the use of off-the-shelf component, and does not require an integrated optics circuit.

Simple real-time noise removal in intensified low-light-level television images

A simple and novel real-time interframe operator substantially reduces short-lived noisy scintillations in low-lightlevel video imaging systems that use image intensifiers.

Geometrical separation between the birefringence components in Faraday-rotation fiber-optic current sensors

A novel optical fiber current sensor for low-current measurements is proposed and tested. By winding a commonly used low-birefringence single-mode optical fiber in a special geometry, one can circumvent the bend-induced birefringence problem. Smaller sensors can now be built with a sensitivity that linearly increases with the number of fiber windings.

Asymmetric behavior of polished polarization-maintaining couplers

Basic asymmetric behavior is experimentally observed in a polished polarization-maintaining fiber coupler. As the two half-couplers are made to slide on top of each other, the output extinction ratio exhibits relatively large variations whose forms depend on the fiber that is selected for the input. We propose that a local distortion of the fiber birefringent axes, which could be caused by the half-coupler polishing process, can generate such features even when the launched light is perfectly polarized along a principal axis of the input fiber.

Probability distribution of phase-induced intensity noise generated by distributed-feedback lasers

Highly non-Gaussian, short-tailed photocurrent distributions due to laser-phase-induced intensity noise have been observed in fiber-optic systems employing distributed-feedback lasers and wideband receivers. This behavior, which has implications for the correct prediction of performance in systems containing intentional or spurious interferometers, results from the cosinusoidal nonlinearity introduced by the interference process. The laser frequency noise is thereby converted to non-Gaussian intensity fluctuations at the system output. The intensitynoise statistics rapidly revert to Gaussian form, however, in systems whose receiver bandwidth is smaller than the laser linewidth.

Aperture-averaged level-crossing probability in an atmospheric communication link

The intensity statistics of light pulses in an atmospheric communication link are studied here for the case of a finite (nonpoint) detector aperture. The calculation of the statistics of the pulse intensities averaged over the aperture is performed by using a discrete aperture model and applying the multidimensional ognormal distribution. The results of the numerical calculations demonstrate the dependence of the level-crossing probability on aperture radius, number of pulses, and the length of a pulse sequence. The level-crossing probabilities were measured experimentally and found to be in close agreement with the theoretical values.

Wave propagation in turbulent media: use of convergence acceleration methods

We propose the use of convergence acceleration methods for the evaluation of integral expressions of an oscillatory nature, often encountered in the study of optical wave propagation in the turbulent atmosphere. These techniques offer substantial savings in computation time with appreciable gain in accuracy. As an example, we apply the Levin u acceleration scheme to the problem of remote sensing of transversal wind profiles.

Mode-coupling analysis of anisotropic polarization-maintaining fibers

We analyze the coupling between the fundamental vector modal fields of two parallel polarization-maintaining fibers. An improved coupled-mode theory is employed, which also applies to anisotropic materials. Results for the array-mode-propagation constants are presented as a function of the relative tilt angle between the principal axes of the two fibers.

Fiber-optic interferometric sensor arrays with freedom from source phase-induced noise

We propose arrays of all-passive remote sensors with freedom from both source phase-induced intensity noise and cross talk between sensors. These arrays employ high-duty-cycle time-domain addressing, utilize laser diodes, and have downlead insensitivity. A synthetic heterodyne demodulation technique is used to prevent environmentally induced signal fading. An experimental all-fiber implementation of a single remote sensor yielded a measured sensitivity of below 40 microrad/ radicalHz at signal frequencies above 600 Hz.

Aperture averaging of the two-wavelength intensity covariance function in atmospheric turbulence

The influence of aperture averaging on the two-wavelength intensity covariance function was experimentally determined for visible (0.63 microm) and infrared (1.06 microm) collinear, approximately spherical beams which propagated through the earth's turbulent atmosphere. Range varied from 1300 to 3250 m, and due to the prevailing atmospheric conditions, most measurements were made in the strong turbulence regimes. Results show that (1) the covariance function monotonically decreases as the receiver aperture size increases; (2) the correlation coefficient attains high values > or = 0.7) even for a relatively small aperture size of 5 mm; (3) while the single wavelength probability distribution of the intensity is approximately lognormal, the experimental two-wavelength conditional probabilities are higher than those predicted by the lognormal model.

Basal perfusion of the cutaneous microcirculation: measurements as a function of anatomic position

Noninvasive optical techniques of photopulse plethysmography (PPG) and laser Doppler velocimetry (LDV) have been used to identify regional variations in the basal skin blood flow of humans. The procedures assess either the volume (PPG) or the volume-velocity product (LDV) of cutaneous blood vessel perfusion. Fifty-two anatomic positions have been studied in 10 normal subjects resting horizontally. The mean perfusion levels were ranked to reveal the variations in cutaneous blood flow as a function of body site. Groups of data were collected into cohorts and average perfusion values for the subjects within each cohort were compared by the Newman-Keuls multiple comparison test. Most transparently, the results reveal a collection of regions (fingers, palms, face, ears) for which cutaneous perfusion is much higher than all other positions. More subtle differences and some unexpected similarities, however, are also apparent and, in some cases, agree or, in others, conflict, with previously published information. With some exceptions, good general agreement between the two techniques was observed.

Noninvasive assessment of local nicotinate pharmacodynamics by photoplethysmography

The local pharmacodynamics of a topical vasodilator (methyl nicotinate) has been followed noninvasively using photopulse plethysmography. This technique is sensitive to changes in blood flow through the cutaneous microcirculation and responds to the pharmacologic stimulus of the vasoactive agent employed. Five different application sites for the drug were studied and the time course of the local effect (i.e., onset, duration, and decay) was recorded. The applied amount of drug elicited, within a short period, a response which was saturable such that the observed increase in blood flow reached a plateau level. The decay of the elevated perfusion required approximately 1 h, suggesting a half-life for elimination of the drug from the skin of about 10 min. This result agrees closely with other reported values and suggests that the pharmacodynamic measurements of this study may prove useful in elucidating aspects of dermal pharmacokinetics.

Laser phase noise effects in fiber-optic signal processors with recirculating loops

The power spectrum of the optical intensity at the output of a single-mode-fiber recirculating delay line driven by a multimode semiconductor laser is shown to exhibit a spectral structure with notches at zero frequency as well as at other multiples of 1/(loop delay). A theoretical model based on laser phase noise is suggested to explain the experimental data.

Fiber-optic signal processor with applications to matrix-vector multiplication and lattice filtering

A new fiber-optic signal processor is proposed to implement systolic matrix-vector multipliers and lattice filters. 10(9) multiplications/sec can be achieved with currently available components for matrix-vector multiplications that involve Toeplitz matrices. A 2 x 2 (Toeplitz) matrix-vector multiplier has been experimentally demonstrated using single-mode fibers and directional couplers. The filtering characteristics of the device are also discussed.

Multiple foci in the range dependence of the intensity fluctuations of a plane wave propagating in a random medium

The differential equation for the fourth-order statistical moment of the field of a plane wave propagating in a two dimensional random medium is solved numerically. Results are presented for the scintillation index when the index-of-refraction correlation function of the medium is Gaussian and gamma (ratio of diffraction length to scattering length) is 50. It is pointed out that the solution has multiple foci, and it is suggested that this characteristic will be more pronounced for larger values of gamma.

Propagation of a finite beam through a random medium

The differential equation for the fourth-order statistical moment of the field of a finite beam propagating in a statistically homogeneous and isotropic two-dimensional random medium is solved numerically. Results are presented for the variance and covariance of irradiance scintillations of a Gaussian beam that propagates in a medium with a Gaussian correlation function. It is shown that the range dependence of the variance is highly dependent on the ratio D/ln (D) is the initial beam width; ln is the correlation length of the medium) and approaches that of a plane wave for large enough D/ln. An increase in the variance toward the edge of the beam is also manifested.