Das THF-9-Natriumoxy-9-borabicyclo[3.3.1]nonan-Tetramer [1] / The THF-9-Sodiooxy-9-borabicyclo[3.3.1]nonane Tetramer [1]

The thermolysis of Na[C8H14B(Et)OH] (2), prepared from 9-Et-9-BBN (1) and NaOH, leads at about 100 °C in the presence of NaHBEt3 as catalyst to ethane and the solid NaOBC8H14 (3), which crystallizes with one mole THF as the tetrameric heterocubane 4 in the triclinic space group P1̄. The lattice constants of 4 (at 120 K) are: a = 1127.7(2), b = 1179.5(2), c = 2055.9(4) pm; α = 87.06(2), β = 87.83(2), γ = 75.37(2)°. 4 contains a slightly distorted central Na4O4 cube with C8H14B and THF substituents at the oxygen and the sodium atoms respectively. 3 can also be prepared by heating an equimolar mixture of Na[H2BC8H14] (5) and Na[(HO)2BC8H14] (6), or from (9H-9-BBN)2 and NaOH and from 9-HO-9-BBN and NaH in THF.

[Leaflets and websites on colorectal cancer screening and their quality assessment from experts' views]

In Germany, individuals who have statutory health insurance have free access to colorectal cancer (CRC) screening tests, and can choose between a fecal occult blood test and a screening colonoscopy. Evidence-based health information may support informed choices regarding whether or not to undergo CRC screening. The aim of this study was to assess whether the available German information materials on CRC screening meet evidence-based health information standards. A systematic search was made for print media and websites on CRC screening addressed to German people with average CRC risk (search period for print media August 2010, for websites January-March 2012). The identified information was assessed with a newly developed comprehensive list of criteria. In all, 41 print media, including 28 flyers and 13 brochures, and 36 websites were identified and assessed. These materials reported more often the benefits than the risks of CRC screening, and quantified presentations of benefits and risks were less frequently given. Most of the materials called for participation and did not indicate the option to decide whether or not to attend CRC screening. This bias in favor of screening was increased by fear-provoking or downplayed wording. Most materials included false and misleading information. The requirements for evidence-based patient information were currently not met by most of the leaflets and websites in Germany. Feedback was given to the producers of the leaflets including a discussion of the findings. The results may be used to revise existing leaflets or to develop new health information on CRC screening.

[Secondary prophylaxis of stroke from a neurological perspective]

Patients who have suffered ischemic stroke or transient ischemic attack (TIA) are at high risk of recurrent stroke, myocardial infarction or vascular death. Early pathophysiological based diagnostics and resulting secondary prevention are critical for reduction of stroke risk. Optimization of lifestyle factors, treatment of hypertension, cholesterol reduction with statins and use of antiplatelet agents in non-cardiogenic or anticoagulation in cardiogenic ischemia as well as internal carotid revascularization, in cases of more than 50% diameter stenosis of the internal carotid artery, are proven strategies for reduction of ischemic stroke risk.

Optical illusion alters M1 excitability after mirror therapy: a TMS study

The contralesional primary motor cortex (M1) has been suggested to be involved in the motor recovery after mirror therapy, but whether the ipsilesional M1 is influenced by the contralesional M1 via transcallosal interhemispheric inhibition (IHI) is still unclear. The present study investigated the change of IHI as well as the intracortical inhibition and intracortical facilitation of both M1 induced by training in a mirror with the use of transcranial magnetic stimulation (TMS). In this 2 × 2 factorial design (time × group), healthy subjects exercised standardized motor skills with their right hand on four consecutive days. Either a mirror (mirror group) or a board (control group) was positioned between their hands. Before and after training TMS was applied along with training tests of both hands. Tests were the same motor skills exercised daily by both groups. Tests of the untrained left hand improved significantly more in the mirror group than in the control group after training (P = 0.02) and showed a close correlation with an increase of intracortical inhibition of M1(left). IHI did not show any difference between investigation time points and groups. The present study confirms the previous suggestion of the involvement of the "contralesional" left-side (ipsilateral to the hand behind the mirror) M1 after mirror therapy, which is not mediated by IHI. Even with the same motor skill training (both groups performed same motor skills) but with different visual information, different networks are involved in training-induced plasticity.

[Pseudo-Conn's syndrome with hypokalemic paralysis due to diuretics and licorice abuse]

Dyskalemic paralyses are characterised by single or periodic episodes with muscle weakness that affect mostly the proximal skeletal muscles. Symptoms may last for a few hours or persist for several days, spontaneous recovery is common. Familial cases can be distinguished from secondary, non-familial forms which are based on other diseases, for example, of the thyroid gland, kidneys or gastrointestinal tract. Familial cases are mostly inherited in an autosomal-dominant pattern and belong to the channelopathies. Both groups are characterised by changed potassium levels in the blood during an episode. A detailed and accurate medical history (plus family history, use of medication and eating habits) often easily leads to the diagnosis. Provoking tests or instrumental and histological investigations can help to solve difficult cases. Treatment focuses on relieving acute symptoms and attacks can be managed by correcting the blood potassium to a normal level. Changing eating and/or exercise habits and also permanent medical treatment helps to prevent further attacks.

A randomized phase II trial comparing two doses of lenalidomide for the treatment of stage IV ocular melanoma

e20012

Background: Ocular melanoma is the most common primary intraocular malignancy in adults with an incidence of 4.3 new cases per million. Approximately 50% of patients will develop metastases and the mean survival of those with liver metastases is 8–10 months. There are no effective systemic therapies. Pre-clinical studies of the antiangiogenic and immunomodulatory agent, lenalidomide, have shown promise in animal models of human ocular melanoma. We therefore conducted a phase II trial comparing two doses of oral lenalidomide. Methods: Patients with stage IV ocular melanoma, who met eligibility criteria and demonstrated disease progression, were enrolled on an IRB approved prospective random assignment trial comparing 5 mg and 25 mg of lenalidomide administered once a day orally for 21 days with a 7 day recovery (one cycle). Lesions were measured at baseline and every 3 months and scored for response by RECIST criteria. Patients who completed 3 cycles were eligible for response evaluation. Patients with responding lesions or with stable disease could continue receiving the agent. Toxicity was assessed using the NCI Common Toxicity Criteria. Results: Seventeen patients (13 female, 4 male; mean age 53) met eligibility criteria and were randomized to 5 mg (9 patients) or 25 mg (8 patients) of lenalidomide. The agent was well tolerated at both doses with only three grade 3 toxicities (two decreased ANC and one rash/puritis) requiring dose adjustments. Sixteen patients were eligible for response assessments. Nine patients had progressive disease by RECIST criteria following 3 cycles of therapy. Seven patients (44%) had stable disease for a mean of 7 months (range 6–12 months). There were no RECIST defined responders. There were no differences between the two dose groups with respect to toxicity or disease stabilization. Conclusions: Lenalidomide is well tolerated at doses of 5 mg and 25 mg orally for a 21 day cycle by patients with stage IV ocular melanoma. While no responses were seen, disease stabilization for a mean of 7 months was seen in 44% of patients. This effect was consistent with the pre-clinical animal data. Based on these results, further development of lenalidomide in combination with other agents should be considered for the treatment of metastatic ocular melanoma.

[Table: see text]

Results of a completed phase I clinical trial of CYT-6091: A pegylated colloidal gold-TNF nanomedicine

3586

Background: CYT-6091 is the first tumor-targeted nanomedicine formulation designed to safely deliver an API that itself is not approved for systemic administration due to unacceptable toxicity. CYT-6091, consisting of tumor necrosis factor-α (TNF) covalently linked to pegylated colloidal gold nanoparticles, has been safely administered in preclinical models, demonstrating an increased T1/2 compared to native TNF, a documented trafficking of nanoparticles to tumor, and no hypotension, the known DLT for TNF. Methods: CYT-6091 was tested in a phase I open label trial in solid tumor, advanced stage patients. Patients (n = 3/dose), admitted to the NIH Clinical Center ICU, received two IV injections of CYT-6091 on day 0 and 14. Dosing started at 50 μg/m2 of TNF, up to 600 μg/m2. Vital signs were monitored and blood samples were drawn over 48 h. The primary endpoint of the study was to determine the MTD for CYT-6091. Secondary endpoints included PK, disease response (staged 45 days post treatment by RECIST), and the detection of gold nanoparticles in tumors and in adjacent healthy tissue. Results: Twenty-nine patients were treated. Even at the lowest dose (50 μg/m2), patients exhibited a febrile response, which was mitigated by acetaminophen and indomethacin pretreatment. None of the 29 patients treated with doses of 50–600 μg/m2 showed a DLT hypotensive response, and in fact, no DLT was seen. T1/2 estimates for TNF, administered as CYT-6091, are 120, 131, 127, 146, 112, 113, 266, 371, and 160 minutes for 50, 100, 150, 200, 250, 300, 400, 500, 600 μg/m2, respectively (published T1/2 for native TNF is ∼27 minutes). In the 28 patients eligible for response assessment, there was 1 PR (100 μg/m2 dose, 7 months duration) and 3 SD (2, 2, and 3 months duration). Electron micrographs show gold nanoparticles in tumor biopsies. Conclusions: CYT-6091 is well tolerated at doses up to 600 μg/m2 of TNF, levels 3-times greater than the published MTD for native TNF. CYT-6091 targets tumors in humans. Efficacy studies in combination with chemotherapy are planned.

[Table: see text]

[Automatic detection of perfusion deficits with Bolus Harmonic Imaging]

PURPOSE

The diagnosis of ischemic stroke relies increasingly on the usage of ultrasound-based methods. One of the recent methods is the transcranial, contrast agent-based Bolus Harmonic Imaging (BHI) method. The captured image sequence is manually examined by clinical experts thus resulting in a time-consuming procedure. The purpose of this study is to evaluate three different methods to analyze BHI image sequences automatically for the detection of ischemic brain tissue.

MATERIALS AND METHOD

BHI captures an image sequence that provides information on the dynamic behavior of the ultrasound contrast agents. This image sequence is analyzed using three different procedures. First a system relying on expert knowledge is used to determine perfusion defects. This procedure requires parametric images, which are previously extracted from the image sequence. The parameter images are then categorized by an unsupervised classification method in well-perfused and ischemic tissue by regarding the parametric images as features describing the perfusion. Thirdly, the whole image sequence can be interpreted as a pixel-by-pixel behavior out of contrast agents. The dynamic curve of each pixel can be automatically classified as perfused and ischemic tissue by the K-Means method without extracting parametric images. In all three cases a closing step is necessary for the accurate interpretation of the results. Transcranial ultrasound imaging produces typical stripe artifacts that have to be detected and eliminated. A result image is then created and provides a conclusion about perfusion reduction in brain tissue.

RESULTS

All three methods have been validated on the basis of 26 patients by clinical experts. The segmentation on the contrast agent kinetics has proven to be most effective. According to our patient database, it provides the highest detection accuracy, resulting in a sensitivity of 100% and a specificity of 100%.

CONCLUSION

The presented methods seem to be adequate for detecting ischemic brain tissue. The classification of contrast agent kinetics provides the best results and has further advantages. It is robust with respect to noise and the calculation is fast because the extraction of parametric images is omitted. The very high sensitivity and specificity must be validated in a larger patient population. Reliable and automated detection of perfusion defects at the bedside seems to be possible.

Reliability of modeling evoked flow responses

PURPOSE

Visually evoked flow characterises the relative changes of blood flow velocity in the posterior cerebral artery in response to visual stimulation. The present study is the first to address the reliability of model fitting to evoked flow responses, rigorously defined by Cronbach's alpha.

MATERIALS AND METHODS

We fitted two models to the evoked flow responses recorded from 19 subjects on two different days. Model 1 characterises a harmonic oscillator with frequency omega and damping coefficient xi which (after a delay DeltaT) is driven from zero towards a new equilibrium K by an impulse with magnitude T. Model 2 is the sum of a first order system subjected to a step and a transient smoothed pulse, both again delayed by DeltaT.

RESULTS

Model 1 exhibited slightly smaller fit errors and convergence was less dependent on starting values for the parameters. As judged from the residual noise in the evoked flow response, there was no clear indication of sustained oscillations characterising model 1 exclusively. Both models showed considerable retest errors. Nonetheless, Cronbach's alpha was significant for K and omega, and highest for K.

CONCLUSION

Retest errors were considerable, particularly so for the damping coefficient xi and impulse magnitude T. A physiological interpretation of these parameters is limited by our findings.