Location of biomarkers and reagents within agarose beads of a programmable bio-nano-chip

The slow development of cost-effective medical microdevices with strong analytical performance characteristics is due to a lack of selective and efficient analyte capture and signaling. The recently developed programmable bio-nano-chip (PBNC) is a flexible detection device with analytical behavior rivaling established macroscopic methods. The PBNC system employs ≈300 μm-diameter bead sensors composed of agarose "nanonets" that populate a microelectromechanical support structure with integrated microfluidic elements. The beads are an efficient and selective protein-capture medium suitable for the analysis of complex fluid samples. Microscopy and computational studies probe the 3D interior of the beads. The relative contributions that the capture and detection of moieties, analyte size, and bead porosity make to signal distribution and intensity are reported. Agarose pore sizes ranging from 45 to 620 nm are examined and those near 140 nm provide optimal transport characteristics for rapid (<15 min) tests. The system exhibits efficient (99.5%) detection of bead-bound analyte along with low (≈2%) nonspecific immobilization of the detection probe for carcinoembryonic antigen assay. Furthermore, the role analyte dimensions play in signal distribution is explored, and enhanced methods for assay building that consider the unique features of biomarker size are offered.     

Surface Characteristics,Copper Release,and Toxicity of Nano‐ and Micrometer‐Sized Copper and Copper(II) Oxide Particles: A Cross‐Disciplinary Study

An interdisciplinary and multianalytical research effort is undertaken to assess the toxic aspects of thoroughly characterized nano‐ and micrometer‐sized particles of oxidized metallic copper and copper(II) oxide in contact with cultivated lung cells, as well as copper release in relevant media. All particles, except micrometer‐sized Cu, release more copper in serum‐containing cell medium (supplemented Dulbecco's minimal essential medium) compared to identical exposures in phosphate‐buffered saline. Sonication of particles for dispersion prior to exposure has a large effect on the initial copper release from Cu nanoparticles. A clear size‐dependent effect is observed from both a copper release and a toxicity perspective. In agreement with greater released amounts of copper per quantity of particles from the nanometer‐sized particles compared to the micrometer‐sized particles, the nanometer particles cause a higher degree of DNA damage (single‐strand breaks) and cause a significantly higher percentage of cell death compared to cytotoxicity induced by micrometer‐sized particles. Cytotoxic effects related to the released copper fraction are found to be significantly lower than the effects related to particles. No DNA damage is induced by the released copper fraction.     

Sintering composites made of plasticized W-Mo powders and hafnium oxide

Conclusions The compactibility in uniaxial compacting of plasticated granules of tungsten-molybdenum mixtures and also of multilayer composites of films of the powders of hafnium and tungsten oxides and their cermets, cast using a rubber binder, is considerably higher than that of the dry tungsten powders. The density of the compacted composite specimens increases and linear shrinkage decreases with the increase of pressure to the critical value (500–600 MPa) and then remains unchanged but the final density after sintering at 2000°C does not depend on the compacting pressure.The concentration dependences of shrinkage of the granulated W-Mo powders contain a deep minimum determined evidently by Frenkel's effect caused by the differences in the partial coefficients of heterodiffusion of the components and by the larger interphase surface.Translated from Poroshkovaya Metallurgiya, No. 3(303), pp. 51–57, March, 1988.     

Relation between image-based assessment of distal radius trabecular structure and compressive strength

This study was undertaken to explore the spinal cord segments controlling the canine and human vas deferens and differentiation of the mammalian sympathetic pathways to the vas deferens. Thoracolumbar white communicating rami (WCR) were electrically stimulated in the dogs. Stimulation of the 1st, 2nd, 3rd, and 4th lumbar WCR elicited an elevation of intraluminal pressure of the vas deferens in 2, 10, 16, and 14 of 20 dogs examined, respectively, whereas stimulation of sympathetic chain (between the 13th thoracic and 1st lumbar ganglia), 13th thoracic WCR, intermesenteric plexus, and 5th lumbar WCR showed no response in any of the 10, 2, 12, and 5 dogs examined, respectively. Anatomical study of the 118 human lumbar splanchnic nerves of 55 cadavers showed that almost all lumbar splanchnic nerves (96%) originated from L2 and/or L3 sympathetic chain ganglia (L1-2 spinal cord levels). Comparative anatomical study of the mammalian sympathetic pathways to the vas deferens showed that the caudal mesenteric plexus is not divided in rats, rabbits, cats, and dogs and is partially divided into two plexuses in monkeys and completely in humans and that separation of the sympathetic component in the pelvic nerve (isolation of the sacral splanchnic nerve) is in progress in the primate. These results indicate that spinal cord segments controlling the vas deferens are L1-4 in the dog and probably L1-2 in humans and that differentiation of the sympathetic nerve pathways is proceeding at both main and compensatory pathways to the vas deferens in the primate.     

Both T-helper-1- and T-helper-2-type lymphokines are depressed in posttrauma anergy

BACKGROUND: We have previously shown that an intrinsic postinjury T-cell dysfunction defined as lack of proliferative response to direct stimulation through the T-cell receptor, referred to here as "anergy," occurs in a subgroup of patients with severe trauma and is associated with organ failure. It has been suggested recently that a dominance of T-helper-2 (Th2) lymphokine production might be responsible for immunosuppression and associated with poor patient outcome. Here, we hypothesize that anergy is associated with global failure of T lymphokine (T LK) production, suggesting that poor outcome is not the result of an excess of immunosuppressive T LK (i.e., interleukin (IL)-10) but rather results from lost T-cell regulatory networking. METHODS: Purified T cells from 37 severely injured trauma patients were cultured and stimulated with alphaCD3/alphaCD4, and proliferation was assessed at 72 hours. Anergy is defined as occurring when the patient's T-cell proliferation to alphaCD3/alphaCD4 is less than 50% of the simultaneously run normal proliferation. Culture supernatants were assessed for T LK production by enzyme-linked immunosorbent assay. Clinical severity was measured by the multiple organ dysfunction syndrome (MODS) and Acute Physiology and Chronic Health Evaluation III scores. RESULTS: Anergy occurred in 20 of 37 patients, and it usually appeared at greater than 5 to 7 days after injury. There was a global reduction of T LK production during T-cell anergy (IL-2, 2.5%; interferon (IFN)gamma, 30.5%; IL-4, 11.8%; and IL-10, 16.9%) compared with increased or unchanged T LK production during the nonanergic state (IL-2, 83%; IFNgamma, 230%; IL-4, 110%; and IL-10, 307.9%; p < 0.01). There was a significant direct correlation between depressed IL-4 and depressed IFNgamma (r = 0.620, p < 0.001), indicating a diminished LK production of both types of T-helper cells (Th1 and Th2). Decreased IL-2 and IL-10 levels were also specifically correlated to each other during the anergic state (r = 0.91, p < 0.001). The average MODS score for patients during anergy was significantly higher (7.6) than their MODS score in the absence of anergy (4.0, p = 0.01). When IL-2 and IL-10 were measured simultaneously, a predominance of Th2 LK (IL-10) production would result in an IL-10/IL-2 ratio greater than 1. We found, however, that this ratio was not greater than 1 in 80% of assays in which T cells were anergic (p = 0.01). CONCLUSION: During T-cell anergy there is not a predominance of Th2 lymphokine production but rather a global depression of the T-cell lymphokine profile. Both depressed T-cell proliferation and depressed LK production correlate to poor clinical outcome.     

The local addition of tenoxicam reduces the incidence of low back pain after lumbar epidural anesthesia

BACKGROUND: Postepidural backache is a common postoperative complaint after lumbar epidural anesthesia. Useful interventions to decrease the incidence of postepidural backache would be helpful. METHODS: We performed a prospective, randomized, double-blind study to compare the effect of local addition of tenoxicam on the incidence of postepidural backache after nonobstetric surgery. One thousand unpremedicated ASA physical status I or II patients scheduled for hemorrhoidectomy were assigned randomly to tenoxicam or control groups. Patients in the control group received 25 ml lidocaine, 2%, with epinephrine 1:200,000 epidurally and 4 ml lidocaine, 1%, for local skin infiltration. Patients in the tenoxicam group received 25 ml lidocaine, 2%, with epinephrine 1:200,000 epidurally and 4 ml lidocaine, 1%, with tenoxicam (2 mg) 1:2,000 for local skin infiltration. Patients were interviewed at 24, 48, and 72 h postoperatively using a standard visual analog scale for evaluation of postepidural backache. A patient was considered to have postepidural backache when the postoperative visual analog scale score was higher than the preoperative score. RESULTS: The incidence of postepidural backache in patients in the control group for the 3 days were 22.8%, 17.4%, and 9.2%, all of which were significantly more frequent than observed in the patients in the tenoxicam group (6.8%, 4.0%, and 1.2%, P < 0.01). There was a significant association between backache and multiple attempts at epidural needle insertion. CONCLUSION: In summary, the local addition of tenoxicam reduced the incidence and severity of postepidural backache.     

Visual half-field Stroop effects with spatial separation of words and color targets

Past inconsistencies in the occurrence of differential visual half-field Stroop effects were addressed in two experiments using a visual half-field presentation technique incorporating brief displays (100 ms) and a fixation task designed to ensure proper eye fixation at display onset. Experiment 1 used displays in which distractor words and color targets were presented in contralateral visual fields. Experiment 2 compared contralateral with ipsilateral displays where words and color targets appeared one above the other in the same visual field. Stroop effects were larger whenever a word occupied the right as opposed to the left visual field, regardless of whether the color target was left or right. Results are consistent with the idea that words are processed more efficiently or automatically in right visual field/left hemisphere presentations.     

Cloning and in vitro expression of TPK3, a Toxoplasma gondii homologue of shaggy/glycogen synthase kinase-3 kinases

PURPOSE: An established method of cryostorage that might preserve the vascular and endothelial responses of human femoral arteries (HFAs) to be transplanted as allografts was studied. METHODS: HFAs were harvested from multiorgan donors and stored at 4 degrees C in Belzer solution before cryostorage. One hundred eleven HFA rings were isolated and randomly assigned to 1 control group of unfrozen HFAs and 2 groups of HFAs cryopreserved for 7 and 30 days, respectively. Cryopreservation was performed in Elohes solution containing dimethyl sulfoxide (1.8 mmol/L), and the rate of cooling was 1.6 degrees C/min, until -141 degrees C was reached. The contractile and relaxant responses of unfrozen and frozen/thawed arteries were assessed in organ bath by measurement of isometric force generated by the HFAs. RESULTS: After thawing, the maximal contractile responses to all the contracting agonists tested (KCl, U46619 [a thromboxane A2-mimetic], norepinephrine, serotonin, and endothelin-1) were in the range of 7% to 34% of the responses in unfrozen HFAs. The endothelium-independent relaxant responses to forskolin and verapamil were weakly altered, whereas the endothelium-independent relaxant responses to sodium nitroprusside were markedly reduced. Cryostorage of HFAs also resulted in a loss of the endothelium-dependent relaxant response to acetylcholine. The vascular and endothelial responses were similarly altered in the HFAs cryopreserved for 7 and 30 days. CONCLUSION: The cryopreservation method used provided a limited preservation of HFAs contractility, a good preservation of the endothelium-independent relaxant responses, but no apparent preservation of the endothelium-dependent relaxation. It is possible that further refinements of the cryopreservation protocol, such as a slower rate of cooling and a more controlled stepwise addition of dimethyl sulfoxide, might allow better post-thaw functional recovery of HFAs.