Adaptive focusing for transcranial ultrasound imaging using dual arrays

Ultrasonic brain imaging remains difficult and limited because of the strong aberrating effects of the skull (absorption, diffusion and refraction of ultrasounds): high resolution transcranial imaging would require adaptive focusing techniques in order to correct the defocusing effect of the skull. In this paper, a noninvasive brain imaging device is presented. It is made of two identical linear arrays of 128 transducers located on each side of the skull. It is possible to separate the respective influence of the two bone windows on the path of an ultrasonic wave propagating from one array to the other, and thus estimate at each frequency the attenuation and phase shift locally induced by each bone window. The information obtained on attenuation and phase is used to correct the wave fronts that have to be sent through the skull in order to obtain a good focusing inside the skull. Compared to uncorrected wave fronts, the spatial shift of the focal spot is corrected, the width of the focal spot is reduced, and the sidelobes level is decreased up to 17 dB. Transcranial images of a phantom are presented and exhibit the improvement in image quality provided by this new noninvasive adaptive focusing method.

Influence of the molecular weight and imprint conditions on the formation of capillary bridges in nanoimprint lithography

Sub-100 nm patterns can be duplicated by nanoimprint lithography with high reproducibility, even on 200 mm wafers. Nevertheless, several problems have to be solved before this technique reaches a mature state for industrial applications. Several kinds of defect appear frequently in printed polymers. Some of them are induced by capillary effects and are related to mould deformation. Capillary bridges are observed on the flat surfaces around the pattern areas, or inside the printed structures. In this paper, the influence of the polymer molecular weight (M(w)) on the capillary bridge distribution is presented. It will be shown that for smaller M(w), they appear first around the pattern areas and move towards the structures more rapidly. It is also demonstrated that this evolution depends directly on the printing temperature and pattern filling related to the feature density and the film thickness. Finally, it is shown that the influence of these parameters is related to the polymer viscosity, which is the dominant property of the capillary effects, and a trade-off has to be made between the limitation due to the capillary bridges, the decrease of the temperature, which is important to reduce the cycle time, and the sticking defects.

Patterns of psychotropic medication use among patients with severe depression referred for electroconvulsive therapy: data from the Consortium for Research on Electroconvulsive Therapy

Most studies of trends in antidepressant pharmacotherapy have focused on relatively mildly ill, nonpyschotic outpatients. In this report, we provide detailed information on psychotropic use among patients with unipolar depression participating in a large, multisite electroconculsive therapy (ECT) study. Adequacy of antidepressant medication trials was assessed with the Antidepressant Treatment History Form. Among patients with nonpsychotic depression, 27% (60/220) had not had an adequate trial of an antidepressant before ECT, and 63% (139/220) had had at least one inadequate trial. Surprisingly, 33% (79/243) of nonpsychotic patients had been prescribed an antipsychotic. Among patients with psychotic depression, 95% (101/106) had not been given an adequate combination of an antidepressant and antipsychotic agent, mostly due to low doses of the latter class. Among all patients in the trial, 61% (213/352) had been prescribed at least one benzodiazepine, and only 7% (24/352) had been given a lithium augmentation trial. Use of hypnotic agents and anticonvulsants was common. In conclusion, patients with severe depression referred for ECT with a unipolar depressive episode have high rates of psychotropic usage, much of which is inadequate.

[Above elbow amputation due to acupuncture treatment?]

Opinions of acupuncture experts should always be sought in any lawsuit or claim for compensation involving sequelae of acupuncture treatment. Overall,--in the hands of experienced acupuncturists--acupuncture is very safe but not without minor adverse events. However, serious adverse events are extremely rare, especially the risk of a serious vascular lesion. In contrast, inflammatory bowel disease is an independent and disease specific risk factor for thromboembolism, especially if the disease is highly active.

Time reversal of ultrasound through a phononic crystal

In this Letter, we experimentally investigate time reversal focusing through a phononic crystal consisting of a periodic square arrangement of steel rods in water. An acoustic pulse is transmitted through the medium, received at a transducer array, time reversed and backpropagated. Both spatial focusing and time compression are studied and compared with those obtained through an equivalent disordered medium. With the phononic crystal, we do not observe the "hyperfocusing effect" that is typical of time reversal through disordered samples.

Phosphodiesterase (PDE) 7 in inflammatory cells from patients with asthma and COPD

In inflammatory cells, the low K(m) cyclic adenosine monophosphate (cAMP)-specific phosphodiesterase (PDE) 4 subtype is predominant in terms of expression and function, although more recently it has been suggested that PDE 7 may also play a role in regulating inflammatory cell activity. In the present study, PDE 4 and PDE 7 subtype messenger ribonucleic acid (mRNA) transcripts in CD4 and CD8 lymphocytes from healthy (n=10) and asthmatic (n=10) subjects and polymorphonuclear neutrophils (PMNs) and CD8 lymphocytes obtained from healthy (n=10) and chronic obstructive pulmonary disease (COPD) (n=7) subjects were identified and quantified. PDE 4A, PDE 4B, PDE 4D and PDE 7A mRNA were present in similar quantities in both CD4 and CD8 lymphocytes obtained from healthy and asthmatic subjects and in CD8 lymphocytes obtained from healthy and COPD subjects. Expression of PDE 4C and PDE 7B mRNA was also observed, although transcript levels were low and variable between individuals. In addition, the effects of selective PDE 7 inhibition on both phytohaemagluttinin (PHA)-induced human peripheral blood mixed mononuclear cell (HPBMNC) proliferation and fMLP-induced neutrophil elastase (NE) release were studied. HPBMNC and human neutrophils, isolated from the venous blood of healthy volunteers (n=6) were treated with either a novel selective PDE 7 inhibitor PF 0332040 alone or in combination with rolipram. Proliferation of HPBMNC was stimulated by PHA (2microgml(-1)) and assessed by [(3)H]-thymidine incorporation, while fMLP-induced (100nM) NE release was determined using a chromogenic substrate. Both rolipram (0.003-10microM) and PF 0332040 (0.003-10microM) significantly inhibited PHA-stimulated proliferation of HPBMNC ((**)P<0.01). Co-administration of rolipram (0.3-10microM) and PF 0332040 (0.003-10microM) significantly increased the degree of inhibition observed, compared to when either drug was administered alone ((**)P<0.01). PF 0332040 (0.003-10microM) had no inhibitory effect on NE release from human peripheral blood neutrophils stimulated with fMLP (100nM), while rolipram (0.003-10microM) significantly inhibited neutrophil degranulation ((**)P<0.01). These findings suggest no evidence of altered PDE 4 or PDE 7 mRNA transcript levels in inflammatory cells isolated from the peripheral venous blood of mild asymptomatic asthmatic subjects or stable COPD subjects, however, inhibition of PDE 7 may influence mononuclear cell function.

Stimulus-dependent processing of temporal order

Two distinct conceptualisations of processing mechanisms have been proposed in the research on the perception of temporal order, one that assumes a central-timing mechanism that is involved in the detection of temporal order independent of modality and stimulus type, another one assuming feature-specific mechanisms that are dependent on stimulus properties. In the present study, four different temporal-order judgement tasks were compared to test these two conceptualisations, that is, to determine whether common processes underlie temporal-order thresholds over different modalities and stimulus types or whether distinct processes are related to each task. Measurements varied regarding modality (visual and auditory) and stimulus properties (auditory modality: clicks and tones; visual modality: colour and position). Results indicate that the click and the tone paradigm, as well as the colour and position paradigm, correlate with each other. Besides these intra-modal relationships, cross-modal correlations show dependencies between the click, the colour and the position tasks. Both processing mechanisms seem to influence the detection of temporal order. While two different tones are integrated and processed by a more independent, possibly feature-specific mechanism, a more central, modality-independent timing mechanism contributes to the click, colour and position condition.

The case against evidence-based principles in psychiatry

There is an organized movement by governmental, academic and commercial interests to make evidence-based practice the standard of care in the United States. There is little proof that this model can be adapted to psychiatry. We examine the diagnostic system, the validity of the data from clinical trials and how these are applied to clinical practice. The discipline of psychiatry relies on imprecise and unstable diagnostic criteria. It divides psychiatric disorders into discrete categories based on discussion and consultations among designated experts in the field. The diagnostic system is based on consensus and not experimental evidence. In fact, psychiatric disorders are not discrete. High co-morbidities between disorders and the propensity of one condition to change into another makes the present diagnostic system extremely questionable. Outcomes of clinical trials are defined by fractional reductions in the number and severity of symptoms measured by rating scales and not remission of illness. The data obtained from clinical trials are flawed in design, execution and the selective reporting of outcomes. There is substantial evidence to indicate that both investigators and patients can distinguish between active treatment and placebo in double blind studies. In addition, negative outcomes are frequently not reported. Such evidence impacts not only on the specific study, used as evidence, but invalidates the value of meta analyses. Financial considerations lead to the inclusion of inappropriate subjects into studies and favor newer, patented treatments. When the conclusions derived from evidence-based psychiatry are applied to clinical practice they have little to offer and often produce poor treatment outcomes. In fact, when the data used to support the principles of evidence-based psychiatry are examined, they are unsound. The system itself is best considered an untested hypothesis. The diagnostic system, the manner in which data are gathered, and financial factors combine to produce a system that is misleading and indeed, dangerous.

Catatonia in Autistic Spectrum Disorders: A Medical Treatment Algorithm

Autism is a developmental syndrome with an unknown biology and inadequate therapeutics. Assessing the elements of the syndrome for the presence of depression, psychosis, mania, or catatonia, offers opportunities for systematic intervention. Since almost all descriptions of autism highlight the presence of motor symptoms that characterize catatonia, an assessment for this eminently treatable syndrome is recommended for all patients considered to be autistic. A minimum examination includes a catatonia rating scale and for those patients with defined catatonia, a lorazepam test. For those whose catatonia responds to lorazepam, high dose lorazepam therapy is recommended. If this fails, electroconvulsive therapy is recommended. The assessment and treatment of catatonia offers positive medical therapy for the victims of autism and their families.

Is the practice of ECT ethical?

The ethical principles of medical care are beneficence (doing good), non-maleficence (not doing harm), autonomy (right to refuse or accept treatment), and justice (equality of opportunity). The present practice of ECT meets standards for beneficence, non-maleficence, and autonomy. In many nations, however, the principle of justice is not respected, leading to unavailability of ECT, increased suffering and prolonged illness. The signs of improvement are slowly surfacing in the greater recognition of the efficacy of ECT, greater tolerance to its use, and in establishing treatment standards.

Combinations of genetic changes in the human cAMP-responsive element modulator gene: a clue towards understanding some forms of male infertility?

The cAMP-responsive element modulator (CREM) gene plays a pivotal role in the mouse spermatogenesis, but its role in the human infertility has not been fully established. We performed a mutation screening in 13 Slovenian men with round spermatid arrest and in six controls. Eleven genetic changes have been identified in the human CREM gene, three novel single-nucleotide polymorphisms [within the promoters P1, P3 and intervening sequence 1 (IVS1)], one insertion (IVS2) and one non-sense mutation (exon gamma). Some infertile patients seem to accumulate potentially harmful genetic changes. We identified a patient with no CREM immunoreactive protein that was homozygous for the nucleotide changes in all promoters, IVS 1, 2, 6, and was heterozygous for the mutation in exon gamma. Interestingly, insertion in IVS2 (IVS2-58_55insT) results in a four-fold decrease in binding of nuclear proteins. Computer predictions suggested the presence of a potential novel CREM promoter, however, random amplification of cDNA ends from the human testis cDNA library was not successful in confirming a novel transcription start site of the CREM gene. Screening of a larger number of patients and controls is required to elucidate whether the observed combinations of genetic changes in the CREM gene can explain some forms of male infertility.

Imaging anisotropic and viscous properties of breast tissue by magnetic resonance-elastography

MR-elastography is a new technique for assessing the viscoelastic properties of tissue. One current focus of elastography is the provision of new physical parameters for improving the specificity in breast cancer diagnosis. This analysis describes a technique to extend the reconstruction to anisotropic elastic properties in terms of a so-called transversely isotropic model. Viscosity is treated as being isotropic. The particular model chosen for the anisotropy is appealing because it is capable of describing elastic shear anisotropy of parallel fibers. The dependence of the reconstruction on the particular choice of Poisson's ratio is eliminated by extracting the compressional displacement contribution using the Helmholtz-Hodge decomposition. Results are presented for simulations, a polyvinyl alcohol breast phantom, excised beef muscle, and measurements in two patients with breast lesions (invasive ductal carcinoma and fibroadenoma). The results show enhanced anisotropic and viscous properties inside the lesions and an indication for preferred fiber orientation.

Relief of expressed suicidal intent by ECT: a consortium for research in ECT study

OBJECTIVE

This study assessed the incidence, severity, and course of expressed suicidal intent in depressed patients who were treated with ECT. The data are from the first phase of an ongoing, collaborative multicenter study, the overall aim of which was to compare continuation ECT with pharmacotherapy in the prevention of relapse after a successful course of ECT.

METHOD

Suicidal intent, as expressed by patients during an interview, was scored at baseline and before each ECT session with item 3 on the 24-item Hamilton Depression Rating Scale in 444 patients with unipolar depression.

RESULTS

One hundred thirty-one patients (29.5%) reported suicidal thoughts and acts (score of 3 or 4) at baseline. Scores decreased to 0 after 1 week (three ECT sessions) in 38.2% of the patients, after 2 weeks (six ECT sessions) in 61.1%, and in 80.9% at the end of the course of treatment.

CONCLUSIONS

Expressed suicidal intent in depressed patients was rapidly relieved with ECT. Evidence-based treatment algorithms for major depressive mood disorders should include dichotomization according to suicide risk, as assessed by interview. For patients at risk, ECT should be considered earlier than at its conventional "last resort" position.

Transdermal fentanyl: little absorption in two patients with systemic sclerosis?

Two patients suffering from systemic sclerosis (SSc) were treated with the 25 micro/hr transdermal fentanyl patch for pain from either deltoid muscle tendinitis of the left arm or from ischemia of the left-hand thumb. When the medication was changed to either oral morphine or oral methadone, the effects did not correspond to the drug conversion table. These findings suggest that patients with SSc and other systemic skin diseases may be at risk for limited absorption of transdermal fentanyl. In contrast, no restriction of the absorption of transdermal testosterone was observed.