Time Multiplexed Active Neural Probe with 1356 Parallel Recording Sites.

We present a high electrode density and high channel count CMOS (complementary metal-oxide-semiconductor) active neural probe containing 1344 neuron sized recording pixels (20 µm × 20 µm) and 12 reference pixels (20 µm × 80 µm), densely packed on a 50 µm thick, 100 µm wide, and 8 mm long shank. The active electrodes or pixels consist of dedicated in-situ circuits for signal source amplification, which are directly located under each electrode. The probe supports the simultaneous recording of all 1356 electrodes with sufficient signal to noise ratio for typical neuroscience applications. For enhanced performance, further noise reduction can be achieved while using half of the electrodes (678). Both of these numbers considerably surpass the state-of-the art active neural probes in both electrode count and number of recording channels. The measured input referred noise in the action potential band is 12.4 µVrms, while using 678 electrodes, with just 3 µW power dissipation per pixel and 45 µW per read-out channel (including data transmission).

The CELF1 RNA-Binding Protein Regulates Decay of Signal Recognition Particle mRNAs and Limits Secretion in Mouse Myoblasts.

We previously identified several mRNAs encoding components of the secretory pathway, including signal recognition particle (SRP) subunit mRNAs, among transcripts associated with the RNA-binding protein CELF1. Through immunoprecipitation of RNAs crosslinked to CELF1 in myoblasts and in vitro binding assays using recombinant CELF1, we now provide evidence that CELF1 directly binds the mRNAs encoding each of the subunits of the SRP. Furthermore, we determined the half-lives of the Srp transcripts in control and CELF1 knockdown myoblasts. Our results indicate CELF1 is a destabilizer of at least five of the six Srp transcripts and that the relative abundance of the SRP proteins is out of balance when CELF1 is depleted. CELF1 knockdown myoblasts exhibit altered secretion of a luciferase reporter protein and are impaired in their ability to migrate and close a wound, consistent with a defect in the secreted extracellular matrix. Importantly, similar defects in wound healing are observed when SRP subunit imbalance is induced by over-expression of SRP68. Our studies support the existence of an RNA regulon containing Srp mRNAs that is controlled by CELF1. One implication is that altered function of CELF1 in myotonic dystrophy may contribute to changes in the extracellular matrix of affected muscle through defects in secretion.

I heard about it from a friend: assessing interest in buprenorphine treatment.

BACKGROUND: In the United States, opioid abuse and dependence continue to be a growing problem, whereas treatment for opioid abuse and dependence remains fairly static. Buprenorphine treatment for opioid dependence is safe and effective but underutilized. Prior research has demonstrated low awareness and use of buprenorphine among marginalized groups. This study investigates syringe exchange participants' awareness of, exposure to, and interest in buprenorphine treatment. METHODS: Syringe exchange participants were recruited from a mobile unit performing outreach to 9 street-side sites in New York City. Computer-based interviews were conducted to determine (1) opioid users' awareness of, exposure to, and interest in buprenorphine treatment; and (2) the association between awareness or exposure and interest in buprenorphine treatment. Logistic regression models were used to examine the associations between awareness of, direct exposure (i.e., having taken buprenorphine) or indirect exposure (i.e., knowing someone who had taken buprenorphine)S to, and interest in buprenorphine treatment. RESULTS: Of 158 opioid users, 70% were aware of, 32% had direct exposure to, and 31% had indirect exposure to buprenorphine; 12% had been prescribed buprenorphine. Of 138 opioid users who had never been prescribed buprenorphine, 57% were interested in buprenorphine treatment. In multivariate models, indirect exposure was associated with interest in buprenorphine treatment (adjusted odds ratio [AOR] = 2.65, 95% confidence interval [CI]: 1.22-5.77), but awareness and direct exposure were not. CONCLUSIONS: Syringe exchange participants were mostly aware of buprenorphine and interested in treatment, but few had actually been prescribed buprenorphine. Because indirect exposure to buprenorphine was associated with interest in treatment, future interventions could capitalize on indirect exposure, such as through peer mentorship, to address underutilization of buprenorphine treatment.

Consumer attitudes about opioid addiction treatment: a focus group study in New York City.

OBJECTIVE: To develop effective programs for people who are opioid dependent and to impact the opioid epidemic in New York City, it is crucial to monitor attitudes about opioid addiction treatments among opioid users who have experienced barriers to engagement and retention in addiction treatment. DESIGN: The authors conducted a qualitative study using focus groups. METHODS: Six focus groups in three needle exchanges in New York City were audio recorded, transcribed, and systematically coded. The authors report on the main themes related to the study objectives. PARTICIPANTS: Participants of each needle exchange who were opioid dependent and had some knowledge of both methadone and buprenorphine were eligible. RESULTS: There were four main findings. Participants felt the following: 1) buprenorphine is an appropriate option for those heroin users who are motivated to stop using, 2) they have less control over their addiction treatment with methadone than they would have with buprenorphine, 3) buprenorphine treatment is not accessible to many New York City residents who would benefit from this treatment, and 4) lack of access to buprenorphine treatment is a cause of treatment-related diversion. CONCLUSIONS: Both methadone maintenance and buprenorphine treatment opportunities are necessary to address the diverse treatment needs of opioid-dependent people in New York City. However, the current medical model of buprenorphine treatment may be too restrictive for some opioid-dependent people and may be contributing to the use of illicit buprenorphine. New models to deliver buprenorphine treatment may address these problems.

Versatile dual-technology system for markerless allele replacement in Burkholderia pseudomallei.

Burkholderia pseudomallei is the etiologic agent of melioidosis, a rare but serious tropical disease. In the United States, genetic research with this select agent bacterium is strictly regulated. Although several select agent compliant methods have been developed for allelic replacement, all of them suffer from some drawbacks, such as a need for specific host backgrounds or use of minimal media. Here we describe a versatile select agent compliant allele replacement system for B. pseudomallei based on a mobilizable vector, pEXKm5, which contains (i) a multiple cloning site within a lacZalpha gene for facile cloning of recombinant DNA fragments, (ii) a constitutively expressed gusA indicator gene for visual detection of merodiploid formation and resolution, and (iii) elements required for resolution of merodiploids using either I-SceI homing endonuclease-stimulated recombination or sacB-based counterselection. The homing endonuclease-based allele replacement system is completed by pBADSce, which contains an araC-P(BAD)-I-sceI expression cassette for arabinose-inducible I-SceI expression and a temperature-sensitive pRO1600 replicon for facile plasmid curing. Complementing these systems is the improved Deltaasd Escherichia coli mobilizer strain RHO3. This strain is susceptible to commonly used antibiotics and allows nutritional counterselection on rich media because of its diaminopimelic acid auxotrophy. The versatility of the I-SceI- and sacB-based methods afforded by pEXKm5 in conjunction with E. coli RHO3 was demonstrated by isolation of diverse deletion mutants in several clinical, environmental, and laboratory B. pseudomallei strains. Finally, sacB-based counterselection was employed to isolate a defined chromosomal fabD(Ts) allele that causes synthesis of a temperature-sensitive FabD, an essential fatty acid biosynthesis enzyme.

NFAT expression in human osteoclasts.

Nuclear factor of activated T-cells cytoplasmic (NFATc) is a family of transcription factors originally identified in T-cells. The gene family is currently known to have four members (NFATc1 through NFATc4) which have roles both within and outside the immune system. We show that NFATc1 is the major induced NFAT in human osteoclasts, with expression greatly exceeding that of NFATc2 through NFATc4. In macrophage-like cells in culture, NFATc1 through NFATc4 are expressed at similar low levels. NFATc1 is comprised of five mRNA transcript variants known to encode three different protein isoforms. The mRNA encoding isoform C (mRNA variant 3) was the most expressed with 38 copies per nanogram followed by isoform B (mRNA variant 5) with 17 copies per nanogram of total RNA. Isoform A (mRNA variant 1) and mRNA variants 2 and 4 made up less than 1% of the total NFATc1 expressed. NFATc1 is activated by calcineurin after calcium-calmodulin signalling. The induction of NFATc1 in osteoclasts was not altered in the presence of cyclosporin A, an inhibitor of calcineurin, suggesting that NFATc1 does not participate in autoregulatory activation of its own promoter. The NFATc1 variants expressed by human osteoclasts are not those normally expressed by effector T-cells but are similar to those seen in naïve T-cells.

Osteoclastic potential of human CFU-GM: biphasic effect of GM-CSF.

UNLABELLED: Human osteoclasts can be efficiently generated in vitro from cord blood mononuclear cells and derived CFU-GM colonies. However, CFU-M colonies are poorly osteoclastogenic. Short-term (2-48 h) treatment with GM-CSF stimulates osteoclast formation by proliferating precursors, whereas longer exposure favors dendritic cell formation. INTRODUCTION: Osteoclasts (OC) differentiate from cells of the myelomonocytic lineage under the influence of macrophage-colony stimulating factor (M-CSF) and RANKL. However, cells of this lineage can also differentiate to macrophages and dendritic cells (DC) depending on the cytokine environment. The aims of this study were to develop an efficient human osteoclastogenesis model and to investigate the roles of granulocyte macrophage-colony stimulating factor (GM-CSF) and M-CSF in human OC differentiation. MATERIALS AND METHODS: A human osteoclastogenesis model, using as precursors colony forming unit-granulocyte macrophage (CFU-GM) colonies generated from umbilical cord mononuclear cells cultured in methylcellulose with GM-CSF, interleukin (IL)-3 and stem cell factor (SCF), has been developed. CFU-GM, colony forming unit-macrophage (CFU-M), or mixed colonies were cultured on dentine with soluble RANKL (sRANKL) and human M-CSF with and without GM-CSF. Major endpoints were OC number, dentine resorption, and CD1a+ DC clusters. RESULTS: Osteoclast generation from CFU-GM and mixed colonies treated with M-CSF and sRANKL for 7-14 days was highly efficient, but CFU-M colonies were poorly osteoclastogenic under these conditions. Pretreatment of precursors with M-CSF for 7 or 14 days maintained the precursor pool, but OCs were smaller and resorption was reduced. The effect of GM-CSF treatment was biphasic, depending on the timing and duration of exposure. Short-term treatment (2-48 h) at the beginning of the culture stimulated cell proliferation and enhanced OC formation up to 100%, independent of sRANKL. Longer-term GM-CSF treatment in the presence of sRANKL, however, inhibited OC generation with the formation of extensive CD1a+ DC clusters, accompanied by downregulation of c-Fos mRNA. Delaying the addition of GM-CSF resulted in progressively less inhibition of osteoclastogenesis. CONCLUSIONS: Human CFU-GM, but not CFU-M, progenitors have high osteoclastogenic potential. GM-CSF plays an important role in osteoclastogenesis and has a biphasic effect: Short-term treatment potentiates OC differentiation by proliferating precursors, but persistent exposure favors DC formation.

Caracterizacion de los pacientes con polimiositis y dermatomiositis del Servicio de Reumatologia de Instituto de Seguros Sociales de Medellin, Colombia, 1992-2000 / Characterization of polymyositis and dermatomyositis patients of Servicio de Reumatologia - Instituto de Seguros Sociales de Medellin, Colombia, 1992-2000

Objetivos: Caracterizar la presentación clínica de los pacientes con polimiositis y dermatomiositis en el Servicio de Reumatología del Instituto de Seguros Sociales de Medellín, evaluar su presentación clínica, las manifestaciones sistémicas, su asociación a neoplasias y la respuesta a corticosteroides. Métodos: Se diseñó un estudio descriptivo transversal incluyendo todos los pacientes seguidos entre enero de 1992 y febrero de 2000, con un tiempo de seguimiento mínimo de 6 meses y que cumplieran los criterios definitivos para polimiositis y dermatomiositis, según Bohan y Peter. Resultados: Se incluyen 29 pacientes, 17 con dermatomiositis y 12 con polimiositis, con mayor representación del sexo femenino (4.1/1) y con una edad promedio al momento del diagnóstico de 34,5 años (rango de 4 a 69 años). Las manifestaciones sistémicas más frecuentes fueron la disfagia (69 por ciento) y artralgias/artritis (62 por ciento); la manifestación pulmonar más frecuente fue la EPID (17,2 por ciento) y se documentó neoplasia durante el seguimiento en el 17,2 por ciento de los pacientes siendo más frecuentes en el grupo de mayores de 50 años (55 por ciento). La mortalidad fue del 13,7 por ciento y las causas de muerte fueron EPID y neoplasias (2 casos cada una). El 29,5 por ciento de los pacientes respondieron al tratamiento esteroideo y el 44,5 por ciento mejoraron al combinar un segundo inmunosupresor; en el 26 por ciento de los casos, la gravedad de los pacientes justificó la combinación de esteroides con otro inmunosupresor desde el comienzo del tratamiento. Conclusiones: Encontramos menor frecuencia de EPID y broncoaspiración que lo descrito en la literatura mundial. Las neoplasias fueron más frecuentes en los pacientes diagnosticados después de 50 años de edad. La tercera parte de los pacientes respondió satisfactoriamente a esteroides como única terapia. Los restantes pacientes requirieron uno o más inmunosupresores adicionales por resistencia a esferoides o por la gravedad de su presentación. Se propone seleccionar tempranamente a los pacientes con mayor severidad para utilizar, desde el principio del tratamiento, la combinación de esferoides e inmunosupresores para evitar las complicaciones inherentes al tratamiento esteroideo y prevenir la atrofia muscular como secuela de las miopatías inflamatorias.