Ictal Spiking Patterns Recorded from Temporal Depth Electrodes Predict Good Outcome After Anterior Temporal Lobectomy

Purpose : Investigators have shown that the presence of ictal spiking (IS) recorded from temporal depth electrodes is associated with mesial temporal sclerosis (MTS). We investigated the relation of IS to seizure control and pathology after anterior temporal lobectomy (ATL). Methods : All patients undergoing intracranial ictal monitoring from a single institution since 1989 were identified. Those who did not undergo ATL or had postoperative follow-up of <1 year were excluded. All received at a minimum bilateral temporal depth electrodes. Ictal recordings were reviewed for the presence of IS, and the proportion of seizures with IS was determined for each patient. Outcome was determined by using Engel's classification. Surgical specimens were reviewed for pathology. Statistics used were X 2 , Fisher exact test, and Wilcoxon rank sum. Results : Forty patients with 571 seizures were reviewed. In 292 seizures from 32 patients, IS was seen. Outcomes were 24 class I (22 with IS), five class II (four with IS), three class III (one with IS), seven class IV (four with IS), and one lost to follow-up (with IS). Pathologic review revealed 25 with MTS, 22 of whom had IS. The presence of IS was associated with class I outcomes (p = 0.04), but not MTS (p = 0.06). Patients with class I outcomes had a significantly greater proportion of seizures with IS (mean, 0.58 ± 0.3) compared with other outcomes (mean, 0.30 ± 0.3, p = 0.02). Conclusions : The presence of IS and higher proportion of seizures with IS correlated with good seizure outcome after ATL. This information may be used in preoperative counseling.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65542/1/j.1528-1157.2000.tb00161.x.pd

Outbreak of tropical rat mite (Ornithonyssus bacoti) dermatitis in a home for disabled persons

Five mentally handicapped individuals living in a home for disabled persons in Southern Germany were seen in our outpatient department with pruritic, red papules predominantly located in groups on the upper extremities, neck, upper trunk and face. Over several weeks 40 inhabitants and 5 caretakers were affected by the same rash. Inspection of their home and the sheds nearby disclosed infestation with rat populations and mites. Finally the diagnosis of tropical rat mite dermatitis was made by the identification of the arthropod Ornithonyssus bacoti or so-called tropical rat mite. The patients were treated with topical corticosteroids and antihistamines. After elimination of the rats and disinfection of the rooms by a professional exterminator no new cases of rat mite dermatitis occurred. The tropical rat mite is an external parasite occurring on rats, mice, gerbils, hamsters and various other small mammals. When the principal animal host is not available, human beings can become the victim of mite infestation. Copyright (c) 2007 S. Karger AG, Base

Multiscale photosynthetic exciton transfer

Photosynthetic light harvesting provides a natural blueprint for bioengineered and biomimetic solar energy and light detection technologies. Recent evidence suggests some individual light harvesting protein complexes (LHCs) and LHC subunits efficiently transfer excitons towards chemical reaction centers (RCs) via an interplay between excitonic quantum coherence, resonant protein vibrations, and thermal decoherence. The role of coherence in vivo is unclear however, where excitons are transferred through multi-LHC/RC aggregates over distances typically large compared with intra-LHC scales. Here we assess the possibility of long-range coherent transfer in a simple chromophore network with disordered site and transfer coupling energies. Through renormalization we find that, surprisingly, decoherence is diminished at larger scales, and long-range coherence is facilitated by chromophoric clustering. Conversely, static disorder in the site energies grows with length scale, forcing localization. Our results suggest sustained coherent exciton transfer may be possible over distances large compared with nearest-neighbour (n-n) chromophore separations, at physiological temperatures, in a clustered network with small static disorder. This may support findings suggesting long-range coherence in algal chloroplasts, and provides a framework for engineering large chromophore or quantum dot high-temperature exciton transfer networks.Comment: 9 pages, 6 figures. A significantly updated version is now published online by Nature Physics (2012

Measurement of Rashba and Dresselhaus spin-orbit magnetic fields

Spin-orbit coupling is a manifestation of special relativity. In the reference frame of a moving electron, electric fields transform into magnetic fields, which interact with the electron spin and lift the degeneracy of spin-up and spin-down states. In solid-state systems, the resulting spin-orbit fields are referred to as Dresselhaus or Rashba fields, depending on whether the electric fields originate from bulk or structure inversion asymmetry, respectively. Yet, it remains a challenge to determine the absolute value of both contributions in a single sample. Here we show that both fields can be measured by optically monitoring the angular dependence of the electrons' spin precession on their direction of movement with respect to the crystal lattice. Furthermore, we demonstrate spin resonance induced by the spin-orbit fields. We apply our method to GaAs/InGaAs quantum-well electrons, but it can be used universally to characterise spin-orbit interactions in semiconductors, facilitating the design of spintronic devices

Geochemistry, faunal composition and trophic structure in reducing sediments on the southwest South Georgia margin

Despite a number of studies in areas of focused methane seepage, the extent of transitional sediments of more diffuse methane seepage, and their influence upon biological communities is poorly understood. We investigated an area of reducing sediments with elevated levels of methane on the South Georgia margin around 250 m depth and report data from a series of geochemical and biological analyses. Here, the geochemical signatures were consistent with weak methane seepage and the role of sub-surface methane consumption was clearly very important, preventing gas emissions into bottom waters. As a result, the contribution of methane-derived carbon to the microbial and metazoan food webs was very limited, although sulfur isotopic signatures indicated a wider range of dietary contributions than was apparent from carbon isotope ratios. Macrofaunal assemblages had high dominance and were indicative of reducing sediments, with many taxa common to other similar environments and no seep-endemic fauna, indicating transitional assemblages. Also similar to other cold seep areas, there were samples of authigenic carbonate, but rather than occurring as pavements or sedimentary concretions, these carbonates were restricted to patches on the shells of Axinulus antarcticus (Bivalvia, Thyasiridae), which is suggestive of microbe–metazoan interactions

Genomic changes associated with the evolutionary transition of an insect gut symbiont into a blood-borne pathogen.

The genus Bartonella comprises facultative intracellular bacteria with a unique lifestyle. After transmission by blood-sucking arthropods they colonize the erythrocytes of mammalian hosts causing acute and chronic infectious diseases. Although the pathogen-host interaction is well understood, little is known about the evolutionary origin of the infection strategy manifested by Bartonella species. Here we analyzed six genomes of Bartonella apis, a honey bee gut symbiont that to date represents the closest relative of pathogenic Bartonella species. Comparative genomics revealed that B. apis encodes a large set of vertically inherited genes for amino acid and cofactor biosynthesis and nitrogen metabolism. Most pathogenic bartonellae have lost these ancestral functions, but acquired specific virulence factors and expanded a vertically inherited gene family for harvesting cofactors from the blood. However, the deeply rooted pathogen Bartonella tamiae has retained many of the ancestral genome characteristics reflecting an evolutionary intermediate state toward a host-restricted intraerythrocytic lifestyle. Our findings suggest that the ancestor of the pathogen Bartonella was a gut symbiont of insects and that the adaptation to blood-feeding insects facilitated colonization of the mammalian bloodstream. This study highlights the importance of comparative genomics among pathogens and non-pathogenic relatives to understand disease emergence within an evolutionary-ecological framework

Integrated, multidisciplinary care for hand eczema: design of a randomized controlled trial and cost-effectiveness study

Background: The individual and societal burden of hand eczema is high. Literature indicates that moderate to severe hand eczema is a disease with a poor prognosis. Many patients are hampered in their daily activities, including work. High costs are related to high medical consumption, productivity loss and sick leave. Usual care is suboptimal, due to a lack of optimal instruction and coordination of care, and communication with the general practitioner/occupational physician and people involved at the workplace. Therefore, an integrated, multidisciplinary intervention involving a dermatologist, a care manager, a specialized nurse and a clinical occupational physician was developed. This paper describes the design of a study to investigate the effectiveness and cost-effectiveness of integrated care for hand eczema by a multidisciplinary team, coordinated by a care manager, consisting of instruction on avoiding relevant contact factors, both in the occupational and in the private environment, optimal skin care and treatment, compared to usual, dermatologist-led care. Methods: The study is a multicentre, randomized, controlled trial with an economic evaluation alongside. The study population consists of patients with chronic, moderate to severe hand eczema, who visit an outpatient clinic of one of the participating 5 (three university and two general) hospitals. Integrated, multidisciplinary care, coordinated by a care manager, including allergo-dermatological evaluation by a dermatologist, occupational intervention by a clinical occupational physician, and counselling by a specialized nurse on optimizing topical treatment and skin care will be compared with usual care by a dermatologist. The primary outcome measure is the cumulative difference in reduction of the clinical severity score HECSI between the groups. Secondary outcome measures are the patient's global assessment, specific quality of life with regard to the hands, generic quality of life, sick leave and patient satisfaction. An economic evaluation will be conducted alongside the RCT. Direct and indirect costs will be measured. Outcome measures will be assessed at baseline and after 4, 12, 26 and 52 weeks. All statistical analyses will be performed on the intention-to-treat principle. In addition, per protocol analyses will be carried out. Discussion: To improve societal participation of patients with moderate to severe hand eczema, an integrated care intervention was developed involving both person-related and environmental factors. Such integrated care is expected to improve the patients' clinical signs, quality of life and to reduce sick leave and medical costs. Results will become available in 2011

Knocking down gene expression for growth hormone-releasing hormone inhibits proliferation of human cancer cell lines

Splice Variant 1 (SV-1) of growth hormone-releasing hormone (GHRH) receptor, found in a wide range of human cancers and established human cancer cell lines, is a functional receptor with ligand-dependent and independent activity. In the present study, we demonstrated by western blots the presence of the SV1 of GHRH receptor and the production of GHRH in MDA-MB-468, MDA-MB-435S and T47D human breast cancer cell lines, LNCaP prostate cancer cell line as well as in NCI H838 non-small cell lung carcinoma. We have also shown that GHRH produced in the conditioned media of these cell lines is biologically active. We then inhibited the intrinsic production of GHRH in these cancer cell lines using si-RNA, specially designed for human GHRH. The knocking down of the GHRH gene expression suppressed the proliferation of T47D, MDA-MB-435S, MDA-MB-468 breast cancer, LNCaP prostate cancer and NCI H838 non-SCLC cell lines in vitro. However, the replacement of the knocked down GHRH expression by exogenous GHRH (1–29)NH2 re-established the proliferation of the silenced cancer cell lines. Furthermore, the proliferation rate of untransfected cancer cell lines could be stimulated by GHRH (1–29)NH2 and inhibited by GHRH antagonists MZ-5-156, MZ-4-71 and JMR-132. These results extend previous findings on the critical function of GHRH in tumorigenesis and support the role of GHRH as a tumour growth factor

Efficient propagation of systematic uncertainties from calibration to analysis with the SnowStorm method in IceCube

Efficient treatment of systematic uncertainties that depend on a large number of nuisance parameters is a persistent difficulty in particle physics and astrophysics experiments. Where low-level effects are not amenable to simple parameterization or re-weighting, analyses often rely on discrete simulation sets to quantify the effects of nuisance parameters on key analysis observables. Such methods may become computationally untenable for analyses requiring high statistics Monte Carlo with a large number of nuisance degrees of freedom, especially in cases where these degrees of freedom parameterize the shape of a continuous distribution. In this paper we present a method for treating systematic uncertainties in a computationally efficient and comprehensive manner using a single simulation set with multiple and continuously varied nuisance parameters. This method is demonstrated for the case of the depth-dependent effective dust distribution within the IceCube Neutrino Telescope