• Restorative Dentistry and Endodontics
• /
• 제25권2호
• /
• pp.212-218
• /
• 2000

The recruitment of leukocytes to a site of inflammation is dependent on a complex interplay of a number of cytokines. Monocyte chemoattractant protein-1 (MCP-1) is a potent chemoattractant for monocytes, whereas interleukin-8 (IL-8) has chemotactic activity for neutrophils, lymphocytes, and basophils. The purpose of this study was to determine the effects of several microbes found in infected root canal systems on the production of inflammatoy cytokines, interleukin 8 and monocyte chemoattractant protein-1 from human peripheral blood mononuclear cells (PBMC). Monocytes isolated from peripheral blood were stimulated by group A streptococci (GAS, ATCC 19615), Enterococcus faecalis (ATCC 29212), Streptococcus mutans (ATCC 10449), Streptococcus sanguis (clinical isolate), and Candida albicans (ATCC 90029) respectively. Each of these bacteria induced dose-dependent induction in IL-8 and MCP-1 determined by ELISA. IL-8 production by each bacteria was decreased in the range of the microbe-to-PBMC ratios of 0.1-1.0. Group A streptococci was the week inducer of MCP-1 production. These results suggest that different oral pathogens induce specific dose-dependent patterns of cytokine release. Such patterns may provide a means of control of the type of immune celles particularly with regard to inflammatory leukocyte recruitment.

• Proceedings of the Korean Geotechical Society Conference
• /
• 한국지반공학회 2000년도 가을 학술발표회 논문집
• /
• pp.621-628
• /
• 2000

In this study, the influence of groundwater variation and surface settlement adjacent to the excavation site of subway station on $\bigcirc$$\bigcirc$ Gas station and the $\bigcirc$$\bigcirc$ building is analized. Measurement data of surface settlement, horizontal deformation and groundwater level are used to verify the results of Caspe analytical method and FLAC numerical analysis. Variation of groundwater level adjacent to the excavation site is modelled by the 3-D groundwater flow program, MODFLOW. The results of both the analytical method and the numerical method were quite close to the measurement data of surface settlement.

• Archives of Reconstructive Microsurgery
• /
• 제10권1호
• /
• pp.12-17
• /
• 2001

Recovery of nerve injury is conditioned by various factors including physical state, injured site, cause of injury, and neurorrhaphy Many researchers have reported on regeneration of nerve using end to side neurorrhaphy. The purpose of this study was to examine regeneration of nerve in various conditioned side to side neurorrhaphy. Total of 25 male Sprague-Dawley rats weighing 220 to 250 gm were divided into five groups of five rats each. The group 1, sham group, composed of dissection only without nerve transaction. The group 2, control group, composed of nerve division only without neurorrhaphy or sural nerve graft. The group 3 composed of one segmental sural nerve graft between the tibial and peroneal nerve after division. Group 4 had two segment graft, and the group 5 with three segment graft, each segment being 6mm long and 5 mm apart. The side to side neurorrhaphy was performed between peroneal nerve and tibial nerve using segmental sural nerve graft in rats. We exposed the sciatic nerve, tibial nerve, peroneal nerve, and sural nerve on left side with prone position. The peroneal nerve was cut on the bifurcation site from tibial nerve and the side to side epineurial neurorrhaphy was performed between peroneal nerve and tibial nerve through 6 mm sural nerve segment graft with 11-0 nylon under operating microscope. The electromyography and the weight from ipsilateral tibialis anterior muscle was performed at one month after neurorrhaphy Peroneal and tibial nerve was examined at distal and proximal to the neurorrhaphy site by methylene blue stain under light microscope for histologic appearance. The number of nerve fibers were counted using the image analyzer. Statistically, both in electromyography and number of nerve fibers, the differences in values between the groups were significant.

• Proceedings of the KOSOMBE Conference
• /
• 대한의용생체공학회 1997년도 추계학술대회
• /
• pp.31-34
• /
• 1997

A semiconductor microelectrode array has been successfully used in obtaining single unit recordings from medial giant nerve of clay fish, rat saphenous nerve and abdominal ganglia of aplysia. The recording device fabricated using silicon microfabrication techniques is a depth-probe type and, previously, has been mostly used to record from central nerve system of vertebrates. From invertebrates, and also from peripheral nerves of vertebrates, however, the quality of the recorded signal depends heavily on the recording conditions, such as the proximity of the electrode site to the nerve cells and the size of the neuron. We have modeled the signal to noise ratio as unctions of these parameters and compared the experimental data with the calculated values thus obtained.

• The Korean Journal of Pain
• /
• 제14권1호
• /
• pp.7-11
• /
• 2001

Background: Although several mechanisms of causalgia, which results from a partial injury to the peripheral nerve trunk, have been proposed, whether or not antidromic impulses from the injured neurons contribute to the development of the mechanical hyperalgesia has not been studied. The purpose of this experiment is was to investigate the role of antidromic impulses to the peripheral sensory receptor site on the development of mechanical hyperalgesia in a rat model of peripheral neuropathy. Methods: Rats were prepared with tight ligation of by tightly ligating the left fifth and sixth lumbar spinal nerves. The effect of bupivacaine pretreatment on the development of mechanical hyperalgesia was evaluated by injecting 0.5% bupivacaine (0.3 ml) into the plantar surface of the left hind paw before the skin incision was made. For the control group, normal saline (0.3 ml) was injected instead of bupivacaine. To measure the mechanical hyperalgesia, paw withdrawal thresholds were measured using a series of von Frey hairs. Mechanical hyperalgesia was measured a the day before, and 1, 2, 3, 4, 7, and 14 days after the surgery. Results: The control group showed decreased withdrawal thresholds from the day after the surgery (the values were $14.0{\pm}0.5$, $8.9{\pm}1.3$, $8.4{\pm}1.6$, $6.9{\pm}1.2$, $8.8{\pm}1.5$, $10.5{\pm}1.3$, and $8.6{\pm}1.3$ g; at -1, 1, 2, 3, 4, 7, and 14 days after the surgery, respectively). However, withdrawal thresholds of the bupivacaine-pretreated group showed increased withdrawal thresholds for three days after the surgery ($14.5{\pm}0.3$, $12.6{\pm}1.4$, $12.7{\pm}1.1$, $10.5{\pm}1.3$ g; at 1, 1, 2, 3 days after the surgery). Conclusions: Our result suggests that antidromic impulses to the peripheral sensory receptors are at least partly responsible for the initial development of mechanical hyperalgesia in a rat model of peripheral neuropathy.

• Nuclear Medicine and Molecular Imaging
• /
• 제42권sup1호
• /
• pp.66-70
• /
• 2008

Reports about FDG PET in biliary tumor are limited and there are almost no reports regarding its efficacy. Biliary tumor is divided to intrahepatic and extrahepatic bile duct cancer, and intrahepatic bile duct cancer can be further divided to peripheral type which occurs at lobular duct and hilar type which occurs at hepatic hilum. Surgical resection is the only curative method for bile duct tumor, and accurate staging plays an important role in deciding treatment modality. Among intrahepatic bile duct tumors, peripheral type and hilar type have the same histological characteristics, but different clinical manifestations and tumor growth pattern. On PET image, FDG uptake is also different between peripheral type and hilar type. Most of the former shows high FDG uptake at primary and metastasis site so it is very useful for determining stage and changing treatment plans. However, the later is diversified among low uptake and very high uptake. The FDG uptake pattern of hilar type is similar to that of extrahepatic bile duct cancer, and mucinous component is an important factor, which affects FOG uptake. When tumor cells are scattered in desmoplatsic stroma, then FDG uptake is low as well. In contrast, when FDG uptake is high, it is likely to be tubular type which has high tumor density. Tumor growth pattern also affects FDG uptake. Nodular type mostly takes higher FDG compared to infiltrative type. There are many cases where benign inflammatory diseases take high FDG that PET alone can not distinguish malignant lesion from benign lesion. In conclusion, studies about PET using FDG are still limited. Thus, it is hard to make accurate conclusion about the roles of PET or PET/CT in biliary cancers, but peripheral type intrahepatic bile duct cancers and mass forming hilar and extrahepatic bile duct cancers appear to be good indications performing FDG PET or PET/CT.

• Journal of Yeungnam Medical Science
• /
• 제17권1호
• /
• pp.12-20
• /
• 2000

The memory of pain can be more damaging than its initial experience. Several factors arc related the directions of pain memory: current pain intensity, emotion, expectation of pain, and peak intensity of previous pain. The possible mechanisms behind the memory of pain are neuroplastic changes of nervous system via peripheral and central sensitization. Peripheral sensitization is induced by neurohumoral alterations at the site of injury and nearby. Biochemicals such as K+, prostaglandins, bradykinin, substance P, histamine and serotonin, increase transduction and produce continuous nociceptive input. Central sensitization takes place within the dorsal horn of spinal cord and amplifies the nociceptive input from the periphery. The mechanisms of central sensitization involve a variety of transmitters and postsynaptic mechanisms resulting from the activations of NMDA receptors by glutamate. and activation of NK-1 tachykinnin receptors by substance-P and neurokinnin. The clinical result of peripheral and central sensitization is hyperalgesia, allodynia, spontaneous pain, referred pain, or sympathetically maintained pain. These persistent sensory responses to noxious stimuli arc a form of memory. The hypothesis of preemptive analgesia is that analgesia administered before the painful stimulus will prevent or reduce subsequent pain and analgesic requirements in comparison to the identical analgesic intervention administered after the painful stimulus, by preventing or reducing the memory of pain in the nervous system. Conventionally, pain management was initiated following noxious stimuli such as surgery. More recently, however many have endorsed preemptive analgesia initiated before surgery. Treatments to control postsurgical pain are often best started before injury activates peripheral nociceptors and triggers central sensitization. Such preemption is not achieved solely by regional anesthesia and drug therapy but also requires behavioral interventions to decrease anxiety or stress. Although the benefit of preemptive analgesia may not be obvious in every circumstance, and in many cases may not sufficient to abolish central sensitization, it is an appropriate and human goal of clinical practice.

• Clinical and Experimental Pediatrics
• /
• 제58권11호
• /
• pp.454-458
• /
• 2015

Compartment syndrome is a rare but devastating condition that can result in permanent neuromuscular or soft tissue injuries. Extravasation injuries, among the iatrogenic causes of compartment syndrome, occur under a wide variety of circumstances in the inpatient setting. Total parenteral nutrition via a peripheral route is an effective alternative for the management of critically ill children who do not obtain adequate nutrition via the oral route. However, there is an inherent risk of extravasation, which can cause compartment syndrome, especially when detected at a later stage. Herein, we report a rare case of compartment syndrome and skin necrosis due to extravasation, requiring emergency fasciotomy and skin graft in a 7-month-old boy who was treated with peripheral parenteral nutrition via a pressurized infusion pump. Although we cannot estimate the exact time at which extravasation occurred, the extent and degree of the wound suggest that the ischemic insult was prolonged, lasting for several hours. Pediatric clinicians and medical teams should carefully examine the site of insertion of the intravenous catheter, especially in patients receiving parenteral nutrition via a peripheral intravenous catheter with a pressurized infusion pump.

• The Korean Journal of Physiology
• /
• 제15권2호
• /
• pp.73-81
• /
• 1981

Experiments were conducted in ischemic decerebrate cats to study the effects of electroacupuncture and electrical stimulation of peripheral nerve on pain reaction. Flexion reflex was used as an index of pain. The reflex was elicited by stimulating the sural nerve(20 V, 0.5 msec duration) and recorded as a compound action potential from the nerve innervated to the semitendinosus muscle. Electroacupuncture was performed, using a 23-gauge hyperdermic needle, on the tsusanli point in the lateral upper tibia of the ipsilateral hindlimb. The common peroneal nerve was selected as a peripheral nerve which may be associated with electroacupuncture action, as it runs through the tissue portion under the tsusanli point. Both for electroacupuncture and the stimulation of common peroneal nerve a stimulus of 20 V-intensity, 2 msec-duration and 2 Hz-frequency was applied for 60 min. The results are summerized as follows: 1) The electroacupuncture markedly depressed the flexion reflex; this effect was eliminated by systemic application of naloxone $(0.02{\sim}0.12\;mg/kg)$, a specific narcotic antagonist. 2) Similarly, the electrical stimulation of the common peroneal nerve significantly depressed the flexion reflex, the effect being reversed by naloxone. 3) When most of the afferent nerves excluding sural nerve in the ipsilateral hindlimb were cut, the effect of electroacupuncture on the flexion reflex was not observed. Whereas direct stimulation of the common peroneal nerve at the proximal end from the cut resulted in a significant reduction of the flexion reflex, again the effect was reversible by naloxone application. 4) Transection of the spinal cord at the thoracic 12 did not eliminate the effect of peripheral nerve stimulation on the flexion reflex and its reversal by naloxone, although the effect was significantly less than that in the animal with spinal cord intact. These results suggest that: 1) the analgesic effect of an electroacupuncture is directly mediated by the nervous system and involves morphine-like substances in CNS, 2) the site of analgesic action of electroacupuncture resides mainly in the brainstem and in part in the spinal cord.

• Investigative Magnetic Resonance Imaging
• /
• 제22권4호
• /
• pp.240-244
• /
• 2018

Primary extranodal bone lymphoma involving the peripheral extremities is extremely rare. Here, we report a definitive case of diffuse large B-cell lymphoma involving the phalangeal bone of the 3rd finger. Systemic evaluation revealed the lesion as the only site of lymphoma involvement.