Long-Term Stability of Lorazepam in Sodium Chloride 0.9% Stored at Different Temperatures in Different Containers.

Background and Objective: Infusion containing lorazepam is used by geriatric department to limit anxiety disorders in the elderly. Currently, these infusions are prepared according to demand by the nursing staff, but the preparation in advance in a centralized service could improve quality of preparation and time management. The aim of this study was to investigate the long-term stability of this infusion in polypropylene syringes stored at 5 ± 3°C. Then, results obtained were compared with stability data of lorazepam in syringes stored at room temperature, glass bottles at 5 ± 3°C, and glass bottles at room temperature. Method: Eight syringes and 6 bottles of infusion were prepared by diluting 1 mL lorazepam 4 mg in 23 mL of NaCl 0.9% under aseptic conditions. Five syringes and 3 bottles were stored at 5 ± 3°C and 3 syringes and 3 bottles were stored at room temperature for 30 days. During the storage period, particle appearance or color change were periodically checked by visual and microscope inspection. Turbidity was assessed by measurements of optical density (OD) at 3 wavelengths (350 nm, 410 nm, 550 nm). The stability of pH was also evaluated. The lorazepam concentrations were measured at each time point by high-performance liquid chromatography with ultraviolet detector at 220 nm. Results: Solutions were physically unstable in syringes at 5 ± 3°C after 4 days: crystals and a drop of OD at 350 nm were observed. However, pH was stable. After 2 days, solutions were considered as chemically unstable because a loss of lorazepam concentration higher than 10% was noticed: the lower 1-sided confidence limit at 95% was below 90% of the initial concentration. To assess temperature and polypropylene influence, results were compared with those obtained for syringes at room temperature and bottles at 5 ± 3°C and room temperature. Precipitation, drop of OD at 350 nm, and chemical instability were observed in all conditions. Conclusion: Solutions of lorazepam were unstable after 2 days in syringes at 5 ± 3°C. Preparation in advance appears, therefore, not possible for the clinical use. Storage conditions (temperature and form) do not improve the stability.

A robust variant of block Jacobi-Davidson for extracting a large number of eigenpairs: Application to grid-based real-space density functional theory.

In this work, we investigate a block Jacobi-Davidson (J-D) variant suitable for sparse symmetric eigenproblems where a substantial number of extremal eigenvalues are desired (e.g., ground-state real-space quantum chemistry). Most J-D algorithm variations tend to slow down as the number of desired eigenpairs increases due to frequent orthogonalization against a growing list of solved eigenvectors. In our specification of block J-D, all of the steps of the algorithm are performed in clusters, including the linear solves, which allows us to greatly reduce computational effort with blocked matrix-vector multiplies. In addition, we move orthogonalization against locked eigenvectors and working eigenvectors outside of the inner loop but retain the single Ritz vector projection corresponding to the index of the correction vector. Furthermore, we minimize the computational effort by constraining the working subspace to the current vectors being updated and the latest set of corresponding correction vectors. Finally, we incorporate accuracy thresholds based on the precision required by the Fermi-Dirac distribution. The net result is a significant reduction in the computational effort against most previous block J-D implementations, especially as the number of wanted eigenpairs grows. We compare our approach with another robust implementation of block J-D (JDQMR) and the state-of-the-art Chebyshev filter subspace (CheFSI) method for various real-space density functional theory systems. Versus CheFSI, for first-row elements, our method yields competitive timings for valence-only systems and 4-6× speedups for all-electron systems with up to 10× reduced matrix-vector multiplies. For all-electron calculations on larger elements (e.g., gold) where the wanted spectrum is quite narrow compared to the full spectrum, we observe 60× speedup with 200× fewer matrix-vector multiples vs. CheFSI.

[Visualization of the superior vena cava in the supraclavicular acoustic window]. / Darstellbarkeit der Vena cava superior im rechten supraklavikulären Schallfenster.

BACKGROUND: The ultrasound-guided venipuncture of the internal jugular vein for placement of a central venous catheter is well established. For verification of the catheter tip position mostly intracardiac ECG or chest radiography are used. Previously, we established the right supraclavicular fossa view for ultrasound based verification of the catheter placement in the superior vena cava utilizing a microconvex probe. The microconvex probe has a small footprint. However, not all ultrasound systems used in the operating theater are equipped with a microconvex transducer. AIM: Thus, we systematically compared the visibility of intrathoracic vessels obtained by a linear and a microconvex prone via the right supraclavicular view. MATERIAL AND METHODS: We assessed the visibility of the junction of the brachiocephalic veins, the superior vena cava, the right pulmonary artery, the ascending aorta and the internal jugular vein, comparing a linear with a microconvex probe when using the right supraclavicular view in healthy volunteers. The superior vena cava also was identified using Doppler ultrasound. RESULTS: With the microconvex probe the superior vena cava was visible in all 30 healthy volunteers, but with a linear transducer it was visible in only 53 %. The combined view of the superior vena cava and the right pulmonary artery was possible in all cases when using the microconvex probe, but in only 38 % when using the linear probe. The junction of the brachiocephalic veins was seen in 75 % of the volunteers with the microconvex probe and in 38 % with the linear one. The aorta was visible in 87 % of cases with the microconvex transducer, but only in 30 % with the linear probe. The internal jugular vein was always visible with either probe. CONCLUSION: The microconvex transducer as compared to the linear probe is superior in visualizing the superior vena cava. Possible reasons are a smaller footprint, a better degree of freedom for angulation and a greater penetration depth of the microconvex probe.

The Long-Term Effect of a Quality Improvement Intervention in the Management of Bronchiolitis.

Quality improvement interventions have been shown to improve adherence with bronchiolitis treatment guidelines; however, the long-term effect of these interventions is unclear. We show that while such an intervention led to a long-lasting change, this was attenuated with time. Repeated interventions are required to maintain guideline adherence.

Computer analysis of organelle translocation in primary neuronal cultures and continuous cell lines.

Organelle translocation in a number of cell types in tissue culture as seen by high-resolution Zeiss-Nomarski differential interference contrast optics was filmed and analyzed by computer. Principal cell types studied included primary chick spinal cord, chick dorsal root ganglion, ratbrain, and various clones of continuous cell lines. Organelle translocations in all cell types studied exhibited frequent, large changes in velocity during any one translocation. The appearance of particles as seen with Nomarski optics was correlated with their fine structures in one dorsal root ganglion neurite by fixing the cell as it was being filmed and obtaining electron micrographs of the region filmed. This revealed the identity of several organelles as well as the presence of abundant neurotubules but no neurofilaments. Primary cell cultures exhibited more high-velocity organelle movements than continuous cell lines. The net progress of an organelle in a given direction was greater in primary neuronal cells than in fibroblasts or continuous cell lines. These findings are correlated with the literature on organelle translocation and axoplasmic transport.

Isolation and structure of a brain constituent that binds to the cannabinoid receptor.

Arachidonylethanolamide, an arachidonic acid derivative in porcine brain, was identified in a screen for endogenous ligands for the cannabinoid receptor. The structure of this compound, which has been named "anandamide," was determined by mass spectrometry and nuclear magnetic resonance spectroscopy and was confirmed by synthesis. Anandamide inhibited the specific binding of a radiolabeled cannabinoid probe to synaptosomal membranes in a manner typical of competitive ligands and produced a concentration-dependent inhibition of the electrically evoked twitch response to the mouse vas deferens, a characteristic effect of psychotropic cannabinoids. These properties suggest that anandamide may function as a natural ligand for the cannabinoid receptor.

Classic IL-6R signalling is dispensable for intestinal epithelial proliferation and repair.

Inflammatory bowel disease is characterized by disturbed cytokine signalling in the mucosa. Inhibition of the proinflammatory interleukin (IL)-6 pathway is a promising new therapeutic strategy, but safety concerns arise as IL-6 signalling also contributes to epithelial repair of the intestinal mucosa. To which extent IL-6 classic or trans-signalling contributes to intestinal repair remains elusive. We tested the influence of IL-6 classic signalling on intestinal repair and proliferation. Whereas IL-6 induced STAT3 phosphorylation in the colonic cancer cell lines, primary non-malignant intestinal organoids did not respond to IL-6 classic signalling. Mice deficient in intestinal IL-6R (IL-6RΔIEC mice) did not display increased susceptibility to acute dextran sulfate sodium (DSS)-induced colitis. In the azoxymethane DSS model IL-6RΔIEC mice were not protected from inflammation-induced carcinogenesis but showed comparable tumor load to wild-type mice. These data indicate that classic signalling is not the major pathway to transduce IL-6 stimuli into the intestinal epithelium.

Amount and speed of fast axonal transport in diabetes.

Abnormalities in axonal transport have been observed in human and experimental diabetes and may be related to the pathogenesis of diabetic neuropathy. Axonal transport has previously been evaluated by indirect methods. In this study, direct-measurement techniques were applied (with computer-enhanced video-recorded images) for the first time to evaluate intra-axonal organelle speed and frequency (the amount of organelle traffic) in both the anterograde fast component (AFC) and retrograde fast component (RFC) of axonal transport in diabetic nerve. Sciatic nerve and dorsal and ventral nerve roots were studied in the animal model of insulin-dependent diabetes (BB/Wistar rat) and sciatic nerve in the non-insulin-dependent (streptozocin-induced) model of diabetes (STZ-D rat). STZ-D rats were studied at 1 mo, and BB/Wistar rats were studied at 1 and 2 mo of diabetes duration. Statistically significant decreases in peripheral axon organelle speed were found only for RFC at 1 mo of diabetes in both the BB/Wistar (8.1%) and STZ-D (5.4%) rats. The difference was no longer significant in BB/Wistar rats at 2 mo of diabetes. This recovery suggests that the underlying abnormality is reversible. No differences were seen in AFC of any axons, and the only other difference seen was a 5.1% decrement in RFC at 2 mo in the ventral roots. No significant difference was observed in any group for organelle frequencies. Other factors should be considered to explain the decrease in materials transported in accumulation studies. The transient deficits in RFC speed observed remain of undetermined significance in the pathogenesis of diabetic neuropathy.

The regulatory interaction of EVI1 with the TCL1A oncogene impacts cell survival and clinical outcome in CLL.

Dysregulated T-cell leukemia/lymphoma-1A (TCL1A), a modulator in B-cell receptor (BCR) signaling, is causally implicated in chronic lymphocytic leukemia (CLL). However, the mechanisms of the perturbed TCL1A regulation are largely unknown. To characterize TCL1A-upstream networks, we functionally screened for TCL1A-repressive micro-RNAs (miRs) and their transcriptional regulators. We identified the novel miR-484 to target TCL1A's 3'-UTR and to be downregulated in CLL. In chromatin immunoprecipitations and reporter assays, the oncogenic transcription factor of myeloid cells, EVI1, bound and activated the miR-484 promoter. Most common in CLL was a pan-EVI1 transcript variant. EVI1 protein expression revealed distinct normal-tissue and leukemia-associated patterns of EVI1/TCL1A co-regulation. EVI1 levels were particularly low in TCL1A-high CLL or such cellular subsets. Global gene expression profiles from a 337-patient set linked EVI1 networks to BCR signaling and cell survival via TCL1A, BTK and other molecules of relevance in CLL. Enforced EVI1, as did miR-484, repressed TCL1A. Furthermore, it reduced phospho-kinase levels, impaired cell survival, mitigated BCR-induced Ca-flux and diminished the in vitro ibrutinib response. Moreover, TCL1A and EVI1 showed a strongly interactive hazard prediction in prospectively treated patients. Overall, we present regressive EVI1 as a novel regulatory signature in CLL. Through enhanced TCL1A and other EVI1-targeted hallmarks of CLL, this contributes to an aggressive cellular and clinical phenotype.

Calcium dependent modulation of fast axonal transport.

The highly differentiated structure of the neuron poses special problems for the intracellular movement of molecules throughout the cell. Molecular transport distances from the synthesizing neuron cell body along the axon (which has no substantial synthetic capabilities) to the axon terminal are very great. The transported substances, transport support structures, translocator motors, and control elements are currently the focus of intense research. Interruption of this flow of molecules could have disastrous effects upon the cell and ultimately the organism resulting in neuropathological conditions. Calcium plays a critical role in modulating fast-axonal transport (FAT) speeds. Before discussing the effect of calcium on FAT, we summarize our broad perspective on the role of axonal transport in neurologic disease.

Fast axonal transport is modulated by altering trans-axolemmal calcium flux.

Factors involved in fast axonal transport (motor proteins, microtubules, organelles, etc.) have been identified but the molecular mechanism controlling transport is unknown. We used video enhanced microscopy to directly evaluate the effect of calcium on fast axonal transport (FAxT). FAxT alterations included rapid speed decreases (within minutes) in Ca2+ free buffer and rapid speed increases (within seconds) when axons were treated with parathyroid hormone, BAY K 8644, or K+ depolarization. The speed increases were blocked by dihydropyridine Ca2+ channel antagonists. Ryanodine (20 microM), known to block calcium release from subcellular stores, caused a decrease in the rate of retrograde FAxT. Calcium ionophore A23187 (at 1 and 20 micrograms/ml) caused increases in FAxT, an effect also noted only in retrograde moving organelle traffic. Hyper- or hypo-tonic solutions produced no alterations making axoplasmic viscosity changes an unlikely explanation for the speed changes. Reproducible alteration of FAxT by manipulation of Ca2+ levels provides evidence that Ca2+ modulates fast axonal transport. Retrograde transport appears more sensitive to changes in Ca2+ and differential effects on antero- and retro-FAxT mechanisms suggest directional specificity for some of these signals which may be based upon the organelle size. Endogenous substances (e.g. PTH) that trigger axonal Ca2+ changes may rapidly modulate the rate of material delivery in axons. The results are discussed within the context of a Ca2+/calmodulin-dependent modification of the cytoskeletal matrix.

Hyperpathia and sensory level due to parietal lobe arteriovenous malformation.

A 30-year-old man experienced the sudden onset of prickly dysesthesia in the perineum followed by a "heavy" sensation in the left lower extremity. There was no headache. He had a hyperpathic response to pinprick and temperature testing below the T-6 dermatome on the left and a decrease of light touch below T-10, also on the left. A small ruptured arteriovenous malformation was found in the right parietal lobe, medially, well above the thalamus, and in the region of the postcentral gyrus. The case provides rare and precise clinicoanatomic correlation of the discrete somatotopic organization of the sensory cortex. Furthermore, it indicates that sensory disturbances, characterized by a segmental level of abnormal sensation suggestive of a spinal cord or medullary lesion and by hyperpathia suggestive of a spinal, medullary, or thalamic localization, can be caused by a suprathalamic parietal deficit.

Spinal subarachnoid hematomas: clue to a source of bleeding in traumatic lumbar puncture.

Although damage to the veins of Batson's epidural plexus is usually considered the origin of bleeding in traumatic lumbar puncture, a lesion of these veins would not explain the cases in which postmortem examination shows blood confined to the subdural and subarachnoid spaces. In two patients who had lumbar punctures a few days before death, there was subarachnoid hematoma of the cauda equina at autopsy. In one of these cases, the radicular vessels were shown to be the source of bleeding. Spinal subarachnoid and subdural hemorrhages after lumbar puncture may be due to laceration of radicular vessels by the spinal needle.

Amyotrophic lateral sclerosis: effects of acute intravenous and chronic subcutaneous administration of thyrotropin-releasing hormone in controlled trials.

We performed double-blind crossover trials to assess the effects of thyrotropin-releasing hormone (TRH) on amyotrophic lateral sclerosis patients. For acute intravenous trials, 500 mg TRH or placebo with norepinephrine was given at 1-week intervals (16 patients). CSF TRH concentration increased, and clinical side effects appeared with TRH. For chronic studies, 25 mg TRH and a saline placebo were given subcutaneously every day for 3 months (25 patients). CSF TRH level increased 29-fold after a single TRH injection, and mild transient side effects occurred. Vital signs, respiratory function, semiquantitative and quantitative neurologic function, muscle strength by manual and dynamometer testing, and EMG were studied. With daily TRH, 10 patients noted subjective improvement without objective evidence, and 10 patients complained of worsening of the disease with objective decline after TRH was stopped. Statistical analysis, however, showed no beneficial effects from either acute or chronic TRH trials.

Fast axonal transport in amyotrophic lateral sclerosis: an intra-axonal organelle traffic analysis.

Fast transport of intra-axonal organelles was studied in motor nerve from amyotrophic lateral sclerosis (ALS) patients. Organelle traffic in ALS nerves demonstrated a significant increase in anterograde mean speed, while retrograde mean speed was decreased compared with that of controls. Retrograde traffic density (organelles per unit time) was also significantly decreased in the ALS specimens. Anterograde transport machinery is therefore intact and may be responding to the increased physiologic demand of larger motor units. Diminished retrograde speed and organelle traffic density are consistent with a defect in retrograde transport and could impair communication between axon terminals and perikarya.

Ischemic optic neuropathy: a complication of cardiopulmonary bypass surgery.

Ischemic optic neuropathy followed cardiopulmonary bypass surgery in the postoperative period in 7 of 7685 consecutive procedures. Th visual loss was unilateral in four patients and bilateral in three and there was little improvement. This ischemic infarction of the optic nerve disk was attributed to hypotension, hypothermia, and activation of certain complement factors by the bypass procedure.

A novel probe for the cannabinoid receptor.

The 1,1-dimethylheptyl (DMH) homologue of 7-hydroxy-delta 6-tetrahydrocannabinol (3) is the most potent cannabimimetic substance reported so far. Hydrogenation of 3 leads to a mixture of the epimers of 5'-(1,1-dimethylheptyl)-7-hydroxyhexahydrocannabinol or to either the equatorial (7) or to the axial epimer (8), depending on the catalysts and conditions used. Compound 7 discriminates for delta 1-THC (2) in pigeons (ED50 = 0.002 mg/kg, after 4.5 h), at the potency level of 3, and binds to the cannabinoid receptor with a KD of 45 pM, considerably lower than the Ki of 180 pM measured for compound 3 and the Ki of 2.0 nM measured for CP-55940 (1), a widely employed ligand. Tritiated 7 was used as a novel probe for the cannabinoid receptor.

Cannabimimetic activity of novel enantiomeric, benzofuran cannabinoids.

The synthesis of the (2R,3R,4S,6R)-7/(2S,3S,4R,6S)-8 enantiomeric pair of benzofuran cannabinoids is reported together with the 1H and 13C NMR spectral parameters. In benzofuran 8 the configurational arrangement of ligated groups at the stereogenic C(3) atom (through which the terpene moiety is connected to the aromatic ring) is very similar to that of the corresponding atom in natural (3R,4R)-delta 1-tetrahydrocannabinol (delta 1-THC), although their respective Cahn-Ingold-Prelog descriptors are different. In drug-discrimination tests in pigeons and rats, benzofuran 8 is as active as delta 1-THC; in the mouse ring test compound 8 is more active than delta 6-THC. Enantiomer 7 is considerably less active than enantiomer 8 in both tests. These results can be explained by the fact that both 7 and 8 have a dimethylheptyl side chain (which is known to enhance cannabimimetic activity) and that delta 1-THC and benzofuran 8 have closely related conformations, as determined by molecular mechanics.

Cannabinol derivatives: binding to cannabinoid receptors and inhibition of adenylylcyclase.

Several derivatives of cannabinol and the 1,1-dimethylheptyl homolog (DMH) of cannabinol were prepared and assayed for binding to the brain and the peripheral cannabinoid receptors (CB1 and CB2), as well as for activation of CB1- and CB2-mediated inhibition of adenylylcyclase. The DMH derivatives were much more potent than the pentyl (i.e., cannabinol) derivatives. 11-Hydroxycannabinol (4a) was found to bind potently to both CB1 and CB2 (Ki values of 38.0 +/- 7.2 and 26.6 +/- 5.5 nM, respectively) and to inhibit CB1-mediated adenylylcyclase with an EC50 of 58.1 +/- 6.2 nM but to cause only 20% inhibition of CB2-mediated adenylylcyclase at 10 microM. It behaves as a specific, though not potent, CB2 antagonist. 11-Hydroxycannabinol-DMH (4b) is a very potent agonist for both CB1 and CB2 (Ki values of 100 +/- 50 and 200 +/- 40 pM; EC50 of adenylylcyclase inhibition 56.2 +/- 4.2 and 207.5 +/- 27.8 pM, respectively).

Synthetic nonpsychotropic cannabinoids with potent antiinflammatory, analgesic, and leukocyte antiadhesion activities.

Two strategies for the design of therapeutically useful cannabinoids have been combined to produce compounds with greatly increased antiinflammatory activity and with a low potential for adverse side effects. Enantiomeric cannabinoids with a carboxylic acid group at position 7 and with an elongated and branched alkyl sidechain at position 5' have been synthesized and tested for antiinflammatory activity. They were effective when given orally at doses of 10 micrograms/kg in reducing paw edema in mice that had been induced by either arachidonic acid or platelet activating factor. Leukocyte adhesion to culture dishes was also reduced in peritoneal cells from mice in which the cannabinoids were orally administered in the same dose range as for the paw edema tests. Antinociception could be observed in the mouse hot plate assay; however, little stereochemical preference was seen in contrast to the above tests where the 3R,4R compounds are more active than the 3S,4S enantiomers. Finally, in agreement with earlier reports on the naturally occurring pentyl side chain acids, the synthetic acids showed little activity in producing catalepsy in the mouse, suggesting that they would be nonpsychotropic in humans.