System for robotically assisted percutaneous procedures with computed tomography guidance

We present the prototype of an image-guided robotic system for accurate and consistent placement of percutaneous needles in soft-tissue targets under CT guidance inside the gantry of a CT scanner. The couch-mounted system consists of a seven-degrees-of-freedom passive mounting arm, a remote center-of-motion robot, and a motorized needle-insertion device. Single-image-based coregistration of the robot and image space is achieved by stereotactic localization using a miniature version of the BRW head frame built into the radiolucent needle driver. The surgeon plans and controls the intervention in the scanner room on a desktop computer that receives DICOM images from the scanner. The system does not need calibration, employs pure image-based registration, and does not utilize any vendor-specific hardware or software features. In the open air, where there is no needle-tissue interaction, we systematically achieved an accuracy better than 1 mm in hitting targets at 5-8 cm from the fulcrum point. In the phantom, the orientation accuracy was 0.6 degrees, and the distance between the needle tip and the target was 1.04 mm. Experiments indicated that this robotic system is suitable for a variety of percutaneous clinical applications.

Hepatobiliary cystadenoma combined with multiple liver cysts: report of a case

Hepatobiliary cystadenomas are rare benign tumors with malignant potential. They are almost always solitary lesions accompanied by multilocular cysts in the liver, and are difficult to differentiate from cystadenocarcinoma, despite the diagnostic modalities available. This report describes a case of hepatobiliary cystadenoma with multiple cysts in the left hepatic lobe, diagnosed by magnetic resonance imaging in a 48-year-old woman. Abdominal computed tomography revealed only multiple cystic lesions in the left lobe, but cholangiography via a nasogastric biliary drainage tube combined with percutaneous transhepatic cholangiography showed a stenotic region with fine irregularity in the left lateral posterior segmental bile duct and left lateral anterior segmental bile duct. Hepatobiliary cystadenocarcinoma with multiple liver cysts was suspected. We performed left hepatectomy, and microscopic examination confirmed a diagnosis of hepatic cystadenoma with multiple liver cysts. There was no nuclear atypia or mitosis in the epithelium of the locus, which was constructed of simple columnar-to-cuboidal epithelium with basal nuclei. The patient is well without recurrence more than 4 years after surgery.

Functional characterization of the splicing variants of human norepinephrine transporter

Human norepinephrine transporter (NET) displays three splicing variants having different carboxy terminals, hNET, hNET C-t var1 and hNET C-t var2. Functional characterization of these isoforms was performed with transient expression system in COS-7 cells. Cells transfected with hNET C-t var2, but not hNET C-t var1, revealed a significant increase in [(3)H]norepinephrine (NE) uptake and [(3)H]nisoxetine binding as well as hNET, in association with their different cellular localization indicated by immunostaining using NET-specific antisera. Kinetic and pharmacological analyses of [(3)H]NE uptake revealed different characteristics between hNET and hNET C-t var2. These results suggest that hNET C-t var2 may participate in NE transport in a manner different from hNET at noradrenergic synapses or in other tissues including placenta where NET variants were found to exist.

Elimination of colonic patches with lymphotoxin beta receptor-Ig prevents Th2 cell-type colitis

Past studies have shown that colonic patches, which are the gut-associated lymphoreticular tissues (GALT) in the colon, become much more pronounced in hapten-induced murine colitis, and this was associated with Th2-type T cell responses. To address the role of GALT in colonic inflammation, experimental colitis was induced in mice either lacking organized GALT or with altered GALT structures. Trinitrobenzene sulfonic acid was used to induce colitis in mice given lymphotoxin-beta receptor-Ig fusion protein (LTbetaR-Ig) in utero, a treatment that blocked the formation of both Peyer's and colonic patches. Mice deficient in colonic patches developed focal acute ulcers with Th1-type responses, whereas lesions in normal mice were of a diffuse mucosal type with both Th1- and Th2-type cytokine production. We next determined whether LTbetaR-Ig could be used to treat colitis in normal or Th2-dominant, IFN-gamma gene knockout (IFN-gamma(-/-)) mice. Four weekly treatments with LTbetaR-Ig resulted in deletion of Peyer's and colonic patches with significant decreases in numbers of dendritic cells. This pretreatment protected IFN-gamma(-/-) mice from trinitrobenzene sulfonic acid-induced colitis; however, in normal mice this weekly treatment was less protective. In these mice hypertrophy of colonic patches was seen after induction of colitis. We conclude that Th2-type colitis is dependent upon the presence of colonic patches. The effect of LTbetaR-Ig was mediated through prevention of colonic patch hypertrophy in the absence of IFN-gamma. Thus, LTbetaR-Ig may offer a possible treatment for the Th2-dominant form of colitis.

Development of a tracking method for image analysis of time-lapse deformation of trabecular structure in a human bone

A new method to track the deformation of the trabecular structure in a human bone, which determines the dynamic characteristics of bone, was developed using elastic matching. This is a kind of image analysis. By comparing two 3-D images of the same bone taken at different times, this method computes displacement of any points in the bone during the period. This method makes it possible to demonstrate the behavior of the trabecular structure to mechanical loads and to estimate changes in the strength of a bone.

Effects of volatile and intravenous anesthetics on the uptake of GABA, glutamate and dopamine by their transporters heterologously expressed in COS cells and in rat brain synaptosomes

Although the neurotransmitter uptake system is considered a possible target for the presynaptic action of anesthetic agents, observations are inconsistent concerning effects on the transporter and their clinical relevance. The present study examined the effects of volatile and intravenous anesthetics on the uptake of GABA, glutamate and dopamine in COS cells heterologously expressing the transporters for these neurotransmitters and in the rat brain synaptosomes. Halothane and isoflurane, but not thiamylal or thiopental, significantly inhibited uptake by COS cell systems of GABA, dopamine and glutamic acid in a concentration-dependent manner within clinically relevant ranges for anesthesia induced by these agents. Similarly, in synaptosomes halothane and isoflurane but not thiopental significantly suppressed the uptake of GABA and glutamic acid, respectively. These results do not support the hypothesis that volatile and intravenous anesthetics exert their action via specific inhibition of GABA uptake to enhance inhibitory GABAergic neuronal activity. Rather, they suggest that presynaptic uptake systems for various neurotransmitters including GABA may be the molecular targets for volatile anesthetic agents.

Surgical treatment for non-dilated biliary tract with pancreaticobiliary maljunction should include excision of the extrahepatic bile duct

BACKGROUND/AIMS

The authors evaluated the surgical treatment for non-dilated biliary tract with pancreaticobiliary maljunction.

METHODOLOGY

Sixty-nine patients with pancreaticobiliary maljunction were divided into 61 patients with the dilated biliary tract and 8 with the non-dilated biliary tract. The levels of amylase activity in the bile in the gallbladder and the bile duct, the incidence and severity of postoperative cholangitis, and cell proliferating activity of the biliary tract epithelium, examined the proliferating cell nuclear antigen labeling index (PCNALI), were examined.

RESULTS

Of the 61 dilated type patients, 12 were of Ia, 1 was of Ib, 22 were of Ic, 25 were of IV-A, and 1 was of IV-B according to Todani's classification. Cancer was detected in 7 dilated type patients and in 3 non-dilated type patients. A high level of amylase activity was measured in the bile juice in both the gallbladder and bile duct in all of the patients with pancreaticobiliary maljunction. PCNALI of the biliary tract epithelium of the patients without cancer (dilated type: bile duct 11.4%, gallbladder 12.7%; non-dilated type: bile duct 5.9%, gallbladder 13.8%) was higher than that of the patients without pancreaticobiliary maljunction (bile duct 1.5%, gallbladder 1.4%).

CONCLUSIONS

In a non-dilated type, as well as in a dilated type, a high level of amylase activity and increase of cell proliferative activity of the biliary tract epithelium were observed. Therefore, these results suggest that the extrahepatic bile duct should be prophylactically removed in patients with non-dilated type as well as in those with dilated type pancreaticobiliary maljunction.

Structural elucidation of a capsular polysaccharide from a clinical isolate of Bacteroides vulgatus from a patient with Crohn's disease

The structure of a capsular polysaccharide (CPS) from a clinical isolate of Bacteroides vulgatus was elucidated. B. vulgatus IMCJ 1204 was isolated from feces of a patient with Crohn's disease. CPS was prepared by phenol/water extraction of the bacterial cells followed by hydrophobic interaction chromatography and then gel filtration chromatography of the extract. The structure of CPS was determined by chemical analysis and NMR spectroscopy including DQF-COSY, TOCSY, ROESY, HSQC-TOCSY, HMQC and HMBC to be a polysaccharide composed of the following repeating unit: -->3)beta-D-Glcp(1-->6)[alpha-D-GalpNAc(1-->2)beta-D-Galp(1-->4)]beta-D-GlcpNAc(1-->3)alpha-D-Galp(1-->4)beta-D-Manp(1-->.

Three-dimensional medical imaging display with computer-generated integral photography

A 3-D display system for medical imaging by computer-generated integral photography (IP) has been developed. Real 3-D images are generated from 3-D medical images and displayed by simple structure. Each point in 3-D space is reconstructed by the convergence of rays from many pixels on the computer display through the lens array. Only the coordinate of the best point is computed for each pixel on the display. The locations of images projected within 40mm from the display were found to be less than 2.0mm in error. Projected images could be observed with motion parallax within 10 degrees from the front of the display.

Peyer's patches are required for oral tolerance to proteins

To clarify the role of Peyer's patches in oral tolerance induction, BALB/c mice were treated in utero with lymphotoxin beta-receptor Ig fusion protein to generate mice lacking Peyer's patches. When these Peyer's patch-null mice were fed 25 mg of ovalbumin (OVA) before systemic immunization, OVA-specific IgG Ab responses in serum and spleen were seen, in marked contrast to low responses in OVA-fed normal mice. Further, high T-cell-proliferative- and delayed-type hypersensitivity responses were seen in Peyer's patch-null mice given oral OVA before systemic challenge. Higher levels of CD4(+) T-cell-derived IFN-gamma, IL-4, IL-5, and IL-10 syntheses were noted in Peyer's patch-null mice fed OVA, whereas OVA-fed normal mice had suppressed cytokine levels. In contrast, oral administration of trinitrobenzene sulfonic acid (TNBS) to Peyer's patch-null mice resulted in reduced TNBS-specific serum Abs and splenic B cell antitrinitrophenyl Ab-forming cell responses after skin painting with picryl chloride. Further, when delayed-type hypersensitivity and splenic T cell proliferative responses were examined, Peyer's patch-null mice fed TNBS were unresponsive to hapten. Peyer's patch-null mice fed trinitrophenyl-OVA failed to induce systemic unresponsiveness to hapten or protein. These findings show that organized Peyer's patches are required for oral tolerance to proteins, whereas haptens elicit systemic unresponsiveness via the intestinal epithelial cell barrier.

Nerve growth factor down-regulates the expression of norepinephrine transporter in rat pheochromocytoma (PC12) cells

Functional expression of norepinephrine transporter (NET) and its regulation were examined in rat pheochromocytoma cell line, PC12. Nerve growth factor (NGF) decreased [3H]-norepinephrine (NE) uptake in association with a decrease in NET mRNA levels. On the other hand, levels of tyrosine hydroxylase mRNA increased in PC12 cells treated with NGF for 4-24 h, while Oct-2 mRNA levels decreased at 4 h with NGF then recovered for 8-24 h in the presence of NGF. Both bFGF and EGF reduced [3H]NE uptake, although they failed to affect NET mRNA levels. To examine the NET transcriptional regulation, we identified the 5'-noncoding region of rat NET mRNA by the rapid amplification of cDNA end (RACE) method and cloned the 5'-flanking region of NET gene. The newly identified exon encodes the untranslated region of rat NET mRNA upstream of the known 5'-region including ATG start codon. Constructs having green fluorescent protein (GFP) as reporter were made with the cloned NET gene, and promoter activity was examined in CHO and SK-N-SH cells transiently transfected and in PC12 cells stably transfected with NET-GFP constructs. The results indicate that the 2.1 kb NET flanking region displays promoter activity and is responsible for the NGF-induced down-regulation of NET expression.

Mediation by platelet-activating factor of 12-hydroxyeicosatetraenoic acid-induced cytosolic free calcium concentration elevation in neutrophils

12(R)-hydroxyeicosatetraenoic acid (HETE) shows biphasic increase in cytosolic free calcium concentration ([Ca2+]i) in rabbit and human neutrophils; the initial transient phase and the continuous falling phase. 12(S)-HETE was less potent in both species. BN50739, a platelet-activating factor (PAF) receptor antagonist, inhibited both phases of 12(R)-HETE-induced [Ca2+]i rise but did not affect leukotriene B4 (LTB4)-induced [Ca2+]i rise. N-tosyl-L-phenylalanine chloromethyl ketone (TPCK), a PAF synthesis inhibitor, and manoalide, a phospholipase A2 inhibitor, reduced 12(R)-HETE-induced [Ca2+]i rise. These blockers inhibited the continuous phase of [Ca2+]i rise induced by N-formyl-methionyl-leucyl-phenylalanine (FMLP) with little effect on the initial phase. It had no significant effect on LTB4-induced [Ca2+]i rise. SC-41930, a LTB4-receptor antagonist, did not block 12-HETE-induced [Ca2+]i rise. In 12(R)-HETE-, FMLP- and LTB4-stimulated cells, accumulations of cell-associated PAF and released PAF were detected but not in unstimulated cells. BN50739 did not affect the accumulation of cell-associated PAF and release of PAF in 12(R)-HETE-stimulated cells. These results suggest that 12(R)-HETE-induced and partially, FMLP-induced, but not LTB4-induced [Ca2+]i rise are mediated by PAF, which is produced and released by stimulation of the cells by 12(R)-HETE and FMLP, respectively.

Regulation of the development of allodynia by intrathecally administered P2 purinoceptor agonists and antagonists in mice

Effects of agonists and antagonists of P2X-purinoceptors on the regulation of the development of allodynia were examined in mice; the drugs were administered intrathecally to the spinal cord. Suramin (5, 10 microg) and pyridoxalphosphate-6-azophenyl-2', 4'-disulfonic acid (PPADS), antagonists of P2X receptors, inhibited prostaglandin (PG) E(2)-induced allodynia. PPADS did not block glutamate-induced allodynia. alpha,beta-Methylene ATP (alpha, beta-meATP), an agonist of P2X receptor, elicited allodynia. alpha, beta-me ATP-induced allodynia was blocked by co-administration of alpha,beta-meATP with PPADS, MK 801 or N(omega)-nitro-L-arginine methyl ester (L-NAME). Suramin at higher doses (20, 40 microg) induced allodynia, which was inhibited by MK 801 or L-NAME. These results suggest that ATP P2X receptors in the spinal cord are involved in the regulation of tactile allodynia. Glutamate receptor and nitric oxide systems play an important role in the development of allodynia produced by alpha,beta-meATP and suramin.

Mice deficient in Th1- and Th2-type cytokines develop distinct forms of hapten-induced colitis

BACKGROUND & AIMS

Most experimental models for inflammatory bowel disease in mice are associated with production of interferon (IFN)-gamma and other proinflammatory cytokines. We hypothesized that T-helper 2 (Th2)-type cells could also contribute to the colitis and cause inflammation different than that mediated by Th1-type cells.

METHODS

Trinitrobenzene sulfonic acid (TNBS)-induced colitis in C57BL/6 background mice genetically deficient in interleukin (IL)-12 p40 (IL-12(-/-)), IFN-gamma (IFN-gamma(-/-)), or IL-4 (IL-4(-/-)) was examined in comparison with control mice (C57BL/6(+/+)).

RESULTS

C57BL/6(+/+), IFN-gamma(-/-), and IL-12(-/-) mice developed patterns of colitis characterized by distortion of crypts, loss of goblet cells, and mononuclear cell infiltration with fibrosis of the mucosal layer. IL-4(-/-) mice had greater mortality than other groups because of penetrating ulcers; however, survivors developed milder lesions that were limited to focal acute ulceration. Colonic CD4(+) T cells from normal, IFN-gamma(-/-), or IL-12(-/- )mice produced both IL-4 and IL-5.

CONCLUSIONS

In TNBS colitis, Th1-like cytokine responses induce fatal, acute, transmural, and focal types of lesions, whereas Th2-like cytokine responses play a significant role in the diffuse atrophic changes in crypts and the mucosal layer that occur in the late stages of this disease.

Changes in seizure susceptibility to local anesthetics by repeated administration of cocaine and nomifensine but not GBR12935: possible involvement of noradrenergic system

We examined cross-sensitization of cocaine and synthetic local anesthetics to their seizure susceptibility after repeated administration. Seizure susceptibility of procaine and lidocaine increased after the end of two days of treatment with a subconvulsive dose of cocaine. Acute treatment with nomifensine but not GBR12935, a specific inhibitor of the dopamine transporter, facilitated lidocaine-induced convulsion. Furthermore, daily treatment with nomifensine for two days enhanced lidocaine-induced convulsion. These results suggest the possible involvement of the brain noradrenergic system in the changes in seizure susceptibility after repeated administration of some local anesthetics.

Evidence for GABA(A) receptor agonistic properties of ketamine: convulsive and anesthetic behavioral models in mice

We examined the potentiation by ketamine of the gamma-aminobutyric acid(A) (GABA(A)) receptor function using convulsive and anesthetic behavioral models in adult male ddY mice. General anesthetic potencies were evaluated by a rating scale, which provided the data for anesthetic scores, loss of righting reflex, duration, and recovery time. All drugs were administered intraperitoneally. Small subanesthetic doses of ketamine did inhibit tonic seizures induced by a large dose of the GABA(A) receptor antagonist bicuculline (8 mg/kg). The 50% effective dose value was 15 (95% confidence limits 10-22) mg/kg. Even large anesthetic doses (100-150 mg/kg) did not suppress clonic seizures in 50% of the animals. The GABA(A) receptor agonist, muscimol (0.32-1.12 mg/kg), potentiated ketamine-induced anesthesia in a dose-dependent fashion (P < 0.05). Similarly, the benzodiazepine receptor agonist, diazepam (1-3 mg/kg), augmented ketamine anesthesia in a dose-dependent manner (P < 0.05). Bicuculline (2-5 mg/kg) dose-dependently antagonized ketamine-induced anesthesia (P < 0.05). Neither the benzodiazepine receptor antagonist, flumazenil (2-20 mg/kg), nor the GABA synthesis inhibitor, L-allylglycine (200 mg/kg), affected the anesthetic action of ketamine. These results suggest that ketamine has GABA(A) receptor agonistic properties and that ketamine-induced anesthesia is mediated, at least in part, by GABA(A) receptors.

IMPLICATIONS

We examined the potentiation by ketamine of the gamma-aminobutyric acid(A) receptor function using convulsive and anesthetic behavioral models in mice. Subanesthetic doses of ketamine-inhibited tonic convulsions induced by the gamma-aminobutyric acid(A) receptor antagonist bicuculline. The gamma-aminobutyric acid(A) receptor agonist, muscimol, potentiated ketamine-induced anesthesia. Bicuculline antagonized ketamine anesthesia, but the benzodiazepine receptor antagonist, flumazenil, and the gamma-aminobutyric acid synthesis inhibitor, L-allyglycine, did not. The effects of ketamine on the gamma-aminobutyric acid(A) receptors appear to correlate with its anesthetic actions.

Augmented reality visualization system for intravascular neurosurgery

We aimed to construct an augmented reality-based visualization system to support intravascular neurosurgery and evaluate it in clinical environments. Three-dimensional (3D) vascular models are overlaid on motion pictures from X-ray fluoroscopy by 2D/3D registration using fiducial markers. The models are reconstructed from 3D data obtained from X-ray computed tomographic angiography or from magnetic resonance angiography using the marching-cube algorithm. Intraoperative X-ray images are mapped as texture patterns on a screen object which is displayed with the vascular models. Distortion of X-ray fluoroscopy is eliminated by a new technique of screen mesh deformation. A quantity called reprojection distance was introduced to evaluate the reliability of the displayed images. It predicts the maximum registration error around the registered objects. Analyses of reprojection distances were performed using synthetic data consisting of marker coordinates with 2D or 3D errors. The tolerance of reprojection distance for the clinical environment was determined to be 3.0 mm. The system was tested in two clinical cases in which reprojection distances of 2.6 and 2.09 mm were obtained. Construction and evaluation of our prototype system were successfully carried out. Further development is planned employing a range sensor to permit markerless registration.

Alternate mucosal immune system: organized Peyer's patches are not required for IgA responses in the gastrointestinal tract

The progeny of mice treated with lymphotoxin (LT)-beta receptor (LTbetaR) and Ig (LTbetaR-Ig) lack Peyer's patches but not mesenteric lymph nodes (MLN). In this study, we used this approach to determine the importance of Peyer's patches for induction of mucosal IgA Ab responses in the murine gastrointestinal tract. Immunohistochemical analysis revealed that LTbetaR-Ig-treated, Peyer's patch null (PP null) mice possessed significant numbers of IgA-positive (IgA+) plasma cells in the intestinal lamina propria. Further, oral immunization of PP null mice with OVA plus cholera toxin as mucosal adjuvant resulted in Ag-specific mucosal IgA and serum IgG Ab responses. OVA-specific CD4+ T cells of the Th2 type were induced in MLN and spleen of PP null mice. In contrast, when TNF and LT-alpha double knockout (TNF/LT-alpha-/-) mice, which lack both Peyer's patches and MLN, were orally immunized with OVA plus cholera toxin, neither mucosal IgA nor serum IgG anti-OVA Abs were induced. On the other hand, LTbetaR-Ig- and TNF receptor 55-Ig-treated normal adult mice elicited OVA- and cholera toxin B subunit-specific mucosal IgA responses, indicating that both LT-alphabeta and TNF/LT-alpha pathways do not contribute for class switching for IgA Ab responses. These results show that the MLN plays a more important role than had been appreciated until now for the induction of both mucosal and systemic Ab responses after oral immunization. Further, organized Peyer's patches are not a strict requirement for induction of mucosal IgA Ab responses in the gastrointestinal tract.

Effect of the sinus of valsalva on the closing motion of bileaflet prosthetic heart valves

Conventional bileaflet prosthetic mechanical heart valves close passively with backflow. Naturally, the valve has problems associated with closure, such as backflow, water hammer effect, and fracture of the leaflet. On the other hand, in the case of the natural aortic valve, the vortex flow in the sinus of Valsalva pushes the leaflet to close, and the valve starts the closing motion earlier than the prosthetic valve as the forward flow decelerates. This closing mechanism is thought to decrease backflow at valve closure. In this study, we propose a new bileaflet mechanical valve resembling a drawbridge in shape, and the prototype valve was designed so that the leaflet closes with the help of the vortex flow in the sinus. The test valve was made of aluminum alloy, and its closing motion was compared to that of the CarboMedics (CM) valve. Both valves were driven by a computer controlled hydraulic mock circulator and were photographed at 648 frames/s by a high speed charge-coupled device (CCD) camera. Each frame of the valve motion image was analyzed with a personal computer, and the opening angles were measured. The flow rate was set as 5.0 L/min. The system was pulsed with 70 bpm, and the systolic/diastolic ratio was 0.3. Glycerin water was used as the circulation fluid at room temperature, and polystyrene particles were used to visualize the streamline. The model of the sinus of Valsalva was made of transparent silicone rubber. As a result, high speed video analysis showed that the test valve started the closing motion 41 ms earlier than the CM valve, and streamline analysis showed that the test valve had a closing mechanism similar to the natural one with the effect of vortex flow. The structure of the test valve was thought to be effective for soft closure and could solve problems associated with closure.

[A case of hypothyroidism found by delayed awakening after the operation]

We report a case of hypothyroidism found by delayed awakening after surgery. A 55-year-old male patient had been suffering from elevated creatine phosphokinase (CPK) and cartinoembryonic antigen (CEA) of unknown origin before the operation. Laparoscopic cholecystectomy was performed under general anesthesia combined with epidural block. Hypotension, low arterial oxygen saturation, hypothermia and metabolic acidosis developed and continued during the operation. Awakening was delayed for about two hours postoperatively. Specific examination resulted in a definitive diagnosis of hypothyoidism. We should pay careful attention to any patient with elevated CPK and CEA of unknown origin before surgery, continuous hypotension, respiratory and circulatory failure and metabolic disorder during surgery, and delayed awakening after surgery that may be the result of hypothyroidism.

Selective inhibition of monoamine neurotransmitter transporters by synthetic local anesthetics

Synthetic local anesthetics (LAs) have been found to have cocaine-like characteristics with some psychotomimetic action, possibly through monoaminergic neurotransmission. To gain insight into the relation between LA action and monoamine transporters, we investigated the effect of synthetic LAs on neurotransmitter transporters, including monoamine transporters. We used cloned transporter cDNAs and examined transient functional expression in COS cells and stable expression in HeLa cells. Among the LAs tested, procaine and other ester-type LAs inhibited [3H]DA uptake and binding of [3H]2-beta-carbomethoxy-3-beta-(4-fluorophenyl)tropane (CFT), a cocaine analogue, in COS cells expressing rat dopamine transporter (DAT). The inhibition was concentration-dependent. The inhibitory effect on [3H]DA uptake was reversible and not dependent on pH, as observed in HeLa cells stably expressing DAT. Procaine also inhibited uptake of norepinephrine (NE) and serotonin (5-HT) by the norepinephrine transporter (NET) or serotonin transporter (SERT) expressed in COS cells. On the other hand, procaine and other LAs had little or no effect on [3H]GABA and [3H]glutamate uptake in COS cells expressing mouse GABA or rat glutamate/aspartate transporter. IC50 values for [3H]DA uptake inhibition correlated well with those for [3H]CFT binding inhibition, but not with intrinsic anesthetic potency. Kinetic analysis of monoamine uptake inhibition by procaine in COS cells expressing rat DAT, NET or SERT revealed a competitive action similar to that of cocaine. These results demonstrate that certain LAs selectively inhibit monoamine transporters. This might contribute to the cocaine-like psychotomimetic action of certain LAs.

gammadelta T cells regulate mucosally induced tolerance in a dose-dependent fashion

We used gammadelta TCR-deficient (TCRdelta(-/-)) mice to examine the role of gammadelta T cells for induction of mucosal responses and systemic tolerance to high versus low doses of oral antigen. When either TCRdelta(-/-) or TCRdelta(+/+) mice were immunized orally with a high dose of ovalbumin (OVA) prior to parenteral challenge, systemic IgG and IgE antibody responses were markedly reduced in both types of mice, while mucosal IgA responses were reduced only in the TCRdelta(-/-) mice. Reduced T cell proliferative responses and delayed-type hypersensitivity were seen in TCRdelta(-/-) and TCRdelta(+/+) mice given the high dose of OVA. Antigen-induced T(h)1 and T(h)2 cytokine production by splenic CD4(+) T cells was severely inhibited in orally tolerized TCRdelta(-/-) and TCRdelta(+/+) mice. In contrast, while oral tolerance associated with increased levels of IL-10 synthesis was induced by a low dose of OVA in TCRdelta(+/+) mice, the TCRdelta(-/-) mice were not tolerized and failed to produce IL-10. Our findings indicate that gammadelta T cells play a significant immunoregulatory role in IL-10-mediated, low-dose oral tolerance induction, but are not essential participants in the induction of systemic tolerance to orally introduced antigens given in larger doses.

A new safe laparoscopic manipulator system with a five-bar linkage mechanism and an optical zoom

This paper describes a new type of laparoscopic manipulator system designed with regard to its safety and sterilization in medical settings. It consists of a laparoscope manipulator using a five-bar linkage mechanism, an optical zoom called the automatic microzoom laparoscope, and a man-machine interface called the Head-Mouse system. The movement of the laparoscope manipulator in the X-Y plane determines the angle of the laparoscope, and the optical zoom substitutes for back-and-forth movements. This system achieves intrinsic safety and ease of sterilization due to limitations in the range of movement. The system achieves high reliability because of the simplicity of both its mechanism and its software. The newly developed optical zoom avoids the possibility of contact with organs by eliminating the back-and-forth movements of the laparoscope required for close-up observation while preserving a high-quality laparoscopic image. The Head-Mouse system for man-machine interface was designed to avoid incorrect inputs by the surgeon. To evaluate the performance of this newly developed system, an experiment was conducted in which a surgeon used the system to perform an in vivo laparoscopic cholecystectomy on a pig.