• The Korean Journal of Physiology and Pharmacology
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• v.4 no.4
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• pp.311-318
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• 2000

We cultured the rabbit inner medullary collecting duct (IMCD) cells as monolayers on collagen-coated membrane filters, and investigated distribution of the P2Y receptors by analyzing nucleotide-induced short circuit current $(I_{sc})$ responses. Exposure to different nucleotides of either the apical or basolateral surface of cell monolayers stimulated $I_{sc}.$ Dose-response relationship and cross-desensitization studies suggested that at least 3 distinct P2Y receptors are expressed asymmetrically on the apical and basolateral membranes. A $P2Y_2-like$ receptor, which responds to UTP and ATP, is expressed on both the apical and basolateral membranes. In addition, a uracil nucleotide receptor, which responds to UDP and UTP, but not ATP, is expressed predominantly on the apical membrane. In contrast, a $P2Y_1-like$ receptor, which responds to ADP and 2-methylthio-ATP, is expressed predominantly on the basolateral membrane. These nucleotides stimulated intracellular cAMP production with an asymmetrical profile, which was comparable to that in the stimulation of $I_{sc}.$ Our results suggest that the adenine and uracil nucleotides can interact with different P2Y nucleotide receptors that are expressed asymmetrically on the apical and basolateral membranes of the rabbit IMCD cells, and that both cAMP- and $Ca^{2+}-dependent$ signaling mechanisms underlie the stimulation of $I_{sc}$.

• Restorative Dentistry and Endodontics
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• v.11 no.1
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• pp.53-61
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• 1985

This study was conducted to evaluate and compare the apical leakage in the following retrograde techniques; apicoectomys, retrograde filling with zinc oxide eugenol cement, non-zinc and zinc amalgam, and cold-burnished gutta-percha method. One hundred twenty five upper anterior and lower premolar teeth were divided into five above mentioned groups and each tooth was individually prepared for its particular group. The specimens were incubated at $37^{\circ}C$ for 14 days and then were infiltrated by 2% methylene blue for 24 hours. The apical leakage was evaluated by measuring the degree of dye penetration between the filling material and the canal wall. The results were as follows: 1. The cold-burnished gutta-percha group showed the least amount of apical leakage and the apicoectomy group showed the greastest amount of apical leakage. 2. Statistics showed that there were significant differences among the groups (P<0.05), however there was no difference between the zinc oxide eugenol cement retrograde filling group and the non-zinc amalgam retrograde filling group (P>0.05).

• Restorative Dentistry and Endodontics
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• v.3 no.1
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• pp.7-11
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• 1977

One hundred and thirteen human mandibular first molars were injected with china ink, decalcified, cleared and used in study, in vitro, to determine the number of root, the number of root canals, canals per root, frequency and location of transverse anastomoses, frequency and location of lateral canals and frequency of the apical deltas. The results were as follows; 1. Most of the teeth showed three canals, but 21. 25% of the teeth were found to have two canals and 21. 25% of them four canals. 2. In so far as observing two canals per root, 77.0% of teeth were found to have two canals in mesial root and 25.7% of them in distal root. 3. In roots with two canals, the separated apical foramen appeared 59.8% in mesial side and 40.0% in distal side, and the common apical foramen 40.2% in mesial side and 60.0% in distal side. 4. Of the two root canals in one root, 37.3% of the canals were found to have transverse anastomoses and were usually located in the apical third of the root. 5. 25.7% of 113 teeth were found to have lateral canals, and ramifications were mainly located in the apical third of the root.

• Restorative Dentistry and Endodontics
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• v.7 no.1
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• pp.17-24
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• 1981

The purpose of this study is to compare the shape of the apical regions of root canals after instrumentation by various enlarging instruments. 120 extracted, single-rooted human teeth were seperated into 4 experimental groups. Each group provided 30 teeth for experimental use. Group 1 root canals instrumented by the hand-operated Reamer. Group 2 root canals instrumented by the hand-operated H-file. Group 3 root canals instrumented by the hand-operated K-file. Group 4 root canals instrumented by the automated Giromatic file. The results were as follows: 1. The degree of the roundness of the apical regions of root canal walls: 1) Hand-operated instruments were superior to the automated Giromatic file. 2) The Reamer was the most effective instrument among hand-operated instruments 3) There was little difference between the H-file and the K-file. 2. The degree of the smoothness of the apical regions of root canal walls: 1) Root canal walls instrumented by the hand-operated Reamer, H-file and, K-file were generally smooth, and there was little difference among them. 2) Root canal walls instrumented by the automated Giromatic file showed many irregular canal walls. 3. The existance of organic debris in the apical regions of root canals: All organic debris is not removed from root canals, and there was little difference between hand-operated instruments and the automated Giromatic instrument in removing organic debris.

• Restorative Dentistry and Endodontics
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• v.7 no.1
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• pp.59-63
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• 1981

Ninety four human mandibular third molars were chosen to study the anatomy of the root canal. The experimental teeth were injected with china ink, decalcified, cleared and used in study, in vitro, to determine the number of root, the number of root canals, canals per root, frequency and location of transverse anastomoses, frequency and location of lateral canals and frequency of the apical deltas. The results were as follows: 1. Most of the teeth showed two canals, but 17.0% of the teeth were found to have one canal, 17.0% of them three canals, 3.2% of them four canals and l.1% of them five canals. 2. In so far as observing one canal per root, 17.0% of the teeth were found to have one canal in single-rooted tooth, 48.9% of them in mesial root and 58.5% of them in distal root. 3. In roots with two or three canals, the separated apical foramen appeared in 55.6% in single-rooted tooth, 64.3% in mesial side and 80.0% in distal side, and the common apical foramen appeared in 44.4% in single-rooted tooth, 35.7% in mesial side and 20.0% in distal side. 4. Of the two root canals in one root, 19.1% of the canals were found to have transverse anastomoses and were usually located in the apical third of the root. 5. 63.8% of 94 teeth were found to have lateral canals, and ramifications were mainly located in the apical third of the root.

• Restorative Dentistry and Endodontics
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• v.5 no.1
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• pp.47-51
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• 1979

Fifty two human mandibular second molars were chosen to study the anatomy of the root canal. The experimental teeth were injected with china ink, decalcified, cleared and used in study, in vitro, to determine the number of root, the number of root canals, canals per root, frequency and location of transverse anastomoses, frequency and location of lateral canals and frequency of the apical deltas. The results were as follows; 1. Most of the teeth showed three canals, but 19.2% of the teeth were found to have two canals and 9.6% of them four canals. 2. In so far as observing two canals per root, 80.8% of the teeth were found to have two canals in mesial root and 9.6% of them in distal canal. 3. In roots with, two canals, the seperated apical foramen appeared in 59.5% in mesial side and 40.0% in distal side, and the common apical foramen appeared in 40.5% in mesial side and 60.0% in distal side. 4. Of the two root canals in one root, 36.2% of the canals were found to have transverse anastomoses and were usually located in the apical third of the root. 5. 23.1% of 52 teeth were found to have lateral canals, and ramifications were mainly located in the apical third of the root.

• Fisheries and Aquatic Sciences
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• v.25 no.11
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• pp.572-578
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• 2022

An organism's physiological processes and behaviors are regulated by neuropeptides and hormone peptides. The first neuropeptide identified from echinoderms is SALMFamide. The two most well-studied SALMFamide neuropeptides are S1 and S2, which possess myoactivity on apical muscle, tube feet, and the cardiac stomach of starfishes. However, neuropeptide candidates identified from SALMFamide's precursor protein sequence have not been investigated. This study aims to compare the bioactivity of SALMFamide neuropeptides from the starfish Asterias rubens using various starfish muscle preparations. In this study, the bioactivity of the L-type SALMFamide neuropeptides from the starfish A. rubens, AYHTGLPFamide (SALMFa-A) and the derivative AYHSALMFamide (SALMFa-B) was investigated. The neuropeptides were applied on Asterias amurensis apical muscle, tube feet, which revealed that the neuropeptides exhibit relaxing activity on apical muscle but no activity on tube feet. The native SALMFa-A peptide had lower relaxing activity on the apical muscle compared to the derivative peptide SALMFa-B. The relaxing activity of two neuropeptides also was compared with those on the apical muscle of Patiria pectinifera, which revealed relaxing activity as well as SALMFamide-S1 and S2 neuropeptides. Moreover, the investigation of SALMFa-A and SALMFa-B peptides' bioactivity on P. pectinifera cardiac stomach muscle also showed slight relaxing activity.

• Journal of Chest Surgery
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• v.29 no.2
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• pp.227-230
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• 1996

Air space disorders are usually considered medical diseases, although some patients with air space disorders can benefit from surgical intervention. Recently we experienced two cases of bullous emphysema. One case is large bilateral apical bullae and the other is infected large bulls of RUL with bullous emphysema. The patient with large bilateral apical bullae underwent simultaneous operation via bilateral thoracotomy and other patient underwent simultaneous bilateral operation via median sternotomy. Postoperatively, the patient with large bilateral apical bullae showed subjective as well as objective improvement and other patient is resulted subjective improvement.

• Restorative Dentistry and Endodontics
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• v.26 no.2
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• pp.124-126
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• 2001

A case of an unicystic ameloblastoma of the mandible presenting as an apical periodontal cyst was reported. The lesion showed an unilocular radiolucency with well delineated border. Histologic examination revealed that a fibrous cyst wall with a lining that consists of partially of ameloblastic epithelium. The overlying epithelial cells are loosely cohesive and resemble stellate reticulum. The fibrous cyst wall of the cyst is infiltrated by typical follicular ameloblastoma. but devoid of inflammatory reaction in the cystic wall. Some considerations regarding differential diagnosis. pathogenesis and biologic behaviour of the lesion were discussed.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.415.1-415.1
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• 2002

Apical to basal transport of organic cations (OCs) such as tributylmethylammonium (TBuMA), triethyimethylammonium (TEMA). 1-methyl-4-phenylpyridinium (MPP), and berberine across Caco-2 cell monolayers was measured to elucidate the intestinal absorption of OCs. Basal to apical transport of MPP and berberine was larger than apical to basal transport and showed temperature dependency and concentration dependency. indicating that MPP and berberine are secreted into the inteslinal lumen. (omitted)