The research reported in this paper aims at applying the human handwriting skill to improve and facilitate the control of laser-assisted laparoscopic surgery operations performed by gynaecological ...surgeons. For the purpose, a laparoscopic robot was interfaced with a digitizing tablet. This interface, further called the intuitive writing interface (IWI), directly converts the hand trajectory, handwritten on the tablet, into an input signal to the robot. It replaces the traditional complex manipulations performed by the surgeon during manual laparoscopic surgery by natural handwriting. It provides the surgeon with an intuitive 'what-you-draw-is-what-you-cut' control facility by employing his/her familiar handwriting skills to control the laser ablation process accurately. The system was successfully built and tested in vitro. Performance tests on the robot resulted in tracking errors in the order of 1 mm in the target plane at an ablation speed of 20 mm/s. The high accuracy of the system was successfully demonstrated by cutting characters 4 mm high on an apple. These results indicate that laser ablation performance is upgraded by the IWI to the accuracy levels of human handwriting, which is much higher than can be obtained with manual laser laparoscopy. Safety features include the use of pen contact with the tablet as a safety switch, and back drivability in the robot joints for easy manual positioning and evacuation in case of emergency.
A single macrocyclic ligand with two hydroxyethyl pendants L (L
=
3,6,9,16,19,22-hexaaza-6,19-bis(2-hydroxyethyl)tricycle22,2,2,2
11,14triaconta-1,11,13,24,27,29-hexaene) was used to form two new ...dinuclear Pd(II) complexes of
trans-Pd
2LCl
2
2+ and
cis-Pd
2LCl
2
2+, which act as “inorganic proteases” to cleave Met-Ala bond in AcMet-Ala.
Two dinuclear palladium (II) complexes,
trans-Pd
2LCl
2(ClO
4)
2
·
2H
2O and
cis-Pd
2LCl
2Cl
2
·
2H
2O, of a single macrocyclic ligand with two hydroxyethyl pendants, L (L
=
3,6,9,16,19,22-hexaaza-6,19-bis(2-hydroxyethyl)tricyclo22,2,2,2
11,14triaconta-1,11,13,24,27,29-hexaene), have been synthesized as “inorganic proteases” and analyzed by X-ray diffraction method. The two complexes-mediated hydrolytic cleavage of amide bond in acetyl methionyl alanine has been monitored by
1H NMR, showing a moderate hydrolytic rate at 50
°C and pH ca. 1.0. The pendent hydroxyl group is responsible for the hydrolytic reaction.
The effect of melatonin on potassium cyanide-induced neurotoxicity was investigated in vivo. The ED
50 value of potassium cyanide, a;5 measured by induction of tonic and clonic seizures, was ...significantly increased by 1.5- or 1.8-fold by s.c. preinjection of melatonin (20,100 or 345 mg/kg) in mice. The preventive effect of melatonin against potassium cyanide-induced seizures was dose dependent. The LD
50 value of potassium cyanide, based on 24-h mortality, was also significantly increased by 1.3-fold by preinjection of melatonin. Potassium cyanide (8 mg/kg s.c.) increased lipid peroxidation in whole brain of mice, and the increased lipid peroxidation was completely abolished when cyanide-induced seizures wen; stopped by preadministration of melatonin. These results suggest that melatonin, a pineal hormone, may protect against cyanide-induced neurotoxicity with its free radical scavenging effects in mice.
In this report, a single-channel chip fabricated with polymethylmethacrylate (PMMA) material was applied to sampling single pollen cells stained with acridine orange (AO). A home-made Hadamard ...transform (HT) microscopic fluorescence image system was used to detect the fluorescence signal emitted from the cells and obtain 511 × 512-pixel two-dimensional image of single cells, by which single-cell fluorescence was measured accurately and the DNA content was determined quantitatively. The single-cell sampling and the on-line imaging were discussed in detail. The PMMA chip, with a suitable channel approximately 100 µm in depth and 108 µm in width, was proved suitable for single-cell sampling. The HT instrument was well matched to the on-line imaging due to the powerful resolving ability. The reliability of the measurement was evaluated by measuring the fluorescent intensity of AO-stained pollens in the channel for 11 times, with a coefficient of variation (CV) of 2.78%. The method was used for quantitative measurements of DNA contents in two kinds of pollens with satisfactory results, which show that the method is rapid, accurate, and reliable in single-cell analysis.
CBA/J mice immunized with thyroglobulin (Tg) develop an experimental autoimmune thyroiditis (EAT) with lymphocytic infiltration of the thyroid glands, autoantibodies to Tg and occurrence of ...EAT-specific T cells. When these mice were treated for 4 weeks after immunization with 1 mg/week of a monoclonal antibody (mAb) that neutralizes the activity of interferon-gamma (IFN) a beneficial effect on the onset of EAT was observed. Characteristic features of EAT were significantly reduced, including the lymphocytic infiltrations of the thyroid glands and the serum levels of autoantibodies to Tg. Moreover, in lymphoid organs, mAb to IFN-gamma significantly reduced the percentages of Tg-specific CD8+ cells, labeled by the anti-clonotypic mAb AG7. These Tg-specific T cells seem responsible for thyroid damages and disease development, since EAT was simultaneously abrogated. These results show that IFN-gamma plays an essential role in the pathophysiology of EAT and suggest the possibility to treat autoimmune thyroid diseases with mAb to IFN-gamma or drugs able to antagonize the production and/or the action of this cytokine.
Effects of soman, an irreversible cholinesterase (ChE) inhibitor, on
3Hnorepinephrine (NE) release evoked by
N-methyl-
d-aspartate (NMDA) were studied in rat brain cortical slices. Soman inhibited ...NMDA-stimulated
3HNE release in a concentration-dependent manner. This effect was neither reversed by atropine, an antagonist of the muscarinic receptor, nor by
d-tubocurarine, an antagonist of the nicotinic receptor. Incubation of the slices with NMDA antagonists, AP5, MK-801, ketamine or magnesium, resulted in inhibitory effects on NMDA-stimulated
3HNE release. Soman significantly shifted the inhibition curves downward and significant interactions between these chemicals and soman were observed. Glycine potentiated the release of
3HNE stimulated by NMDA, and soman did not alter this effect of glycine. Soman also inhibited the release of
3HNE evoked by K
+ in a concentration-dependent manner. NMDA-stimulated
3HNE release was inhibited by tetrodotoxin (TTX), an antagonist of voltage-dependent sodium channels, and a significant interaction between soman and TTX was observed. The
3HNE release induced by NMDA was dependent on extracellular calcium concentrations and was inhibited by nifedipine, a selective blocker of the L-type voltage-dependent calcium channels (VDCC), or cadmium, a non-specific blocker of VDCC. However, no significant interaction between the effects of soman and calcium, nifedipine, or cadmium was observed. Taken together, the results suggested that: (1) soman has a direct action at non-cholinergic sites; (2) soman may interfere with some of the regulatory sites of the NMDA receptor–ion channel complex; and (3) the voltage-dependent sodium channel, but not VDCC, may be a site of action for soman.
Experimental autoimmune thyroiditis (EAT) with granulomatous histopathology (G-EAT) can be induced by cells from mouse thyroglobulin (MTg)-immunized donors activated in vitro with MTg and IL-12. ...G-EAT lesions reach maximum severity 18–21 days after cell transfer and, if some thyroid follicles remain, lesions almost completely resolve by day 35. CD8+ cells are required for G-EAT resolution. To begin to determine the mechanisms involved in G-EAT resolution, apoptosis in thyroids was analyzed by TUNEL staining. Apoptotic thyrocytes and inflammatory cells were present in the thyroids of both CD8+ and CD8-depleted recipient mice at day 19–21. By day 35, apoptotic cells were rare in thyroids of mice whose lesions had resolved; the few apoptotic inflammatory cells were generally in close proximity to thyroid follicles. Thyroids of CD8-depleted mice had ongoing inflammation at day 35 and most apoptotic cells were thyroid follicular cells. The expression of Fas and Fas ligand (FasL) mRNA in thyroids was also determined by RT-PCR in both CD8+ and CD8-depleted recipient mice. Fas was expressed in normal thyroids and its expression was relatively constant throughout the course of disease. FasL mRNA was not expressed in normal thyroids. FasL mRNA expression generally correlated with G-EAT severity, being maximal at day 21 and diminishing as lesions resolved. However, FasL mRNA expression in thyroids of CD8-depleted mice in which resolution was delayed was decreased compared to thyroids of CD8+ mice with comparable disease severity, suggesting that FasL expressed by CD8+ cells may play a role in G-EAT resolution.
To study the role of IL-4 in development of granulomatous experimental autoimmune thyroiditis (EAT), IL-4 gene-disrupted mice expressing the EAT-susceptible H-2k haplotype were generated and used for ...EAT induction. Spleen cells from mouse thyroglobulin (MTg) and LPS-primed IL-4(+/+) and IL-4(-/-) donors could induce severe granulomatous EAT when spleen cells were activated with MTg and anti-IL-2R mAb in the presence of IL-12. Thyroid lesions had extensive follicular cell proliferation, large numbers of histiocytes, polymorphonuclear leukocytes, and multinucleated giant cells, in addition to lymphocytes and other mononuclear cells. Expression of IFN-gamma gene mRNA and production of IFN-gamma by effector spleen cells stimulated with MTg and IL-12 were similar for both IL-4(+/+) and IL-4(-/-) mice. Although IL-4 was undetectable in IL-4(-/-) mice, expression of mRNA for IL-5, IL-10, and IL-13 and production of IL-5 by both MTg-activated spleen cells and anti-CD3-activated CD4+ T cells were comparable for cells from IL-4(+/+) and IL-4(-/-) mice, indicating that the absence of IL-4 did not prevent production of other Th2 cytokines. Production of MTg-specific IgG1 was very low or undetectable in IL-4(-/-) mice. IL-4 gene mRNA and MTg-specific IgG1 could be detected in IL-4(+/+) or IL-4(-/-) recipients only when they received effector cells from IL-4(+/+) donor mice, indicating that IL-4- and IgG1-secreting cells are of donor origin. These results demonstrate that IL-4 is not essential for development of granulomatous EAT.
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