Mutation of the Chk1 Gene in Gastric Cancers with Microsatellite Instability

PURPOSE: The protein kinase Chk1 is required for cell cycle arrest in response to DNA damage and is shown to play an important role in the G2/M checkpoint. The aim of this study was to investigate the relationship between microsatellite instability and frameshift mutation of the Chk1 gene in gastric cancers. MATERIALS AND METHODS: The microsatellite instability was analyzed in 95 primary gastric carcinomas by using microdissection and 6 microsatellite markers. We also performed single strand conformational polymorphism and sequencing to detect frameshift mutation of the Chk1 gene. RESULTS: We found positive microsatellite instability in 19 (20%) of the 95 gastric cancers, 13 high- and 6 low-frequency microsatellite instability cases. The frameshift mutation of Chk1, which resulted in a truncated Chk1 protein, was detected in two high-frequency microsatellite instability cases. CONCLUSION: These data suggest that the microsatellite instability may contribute to the development of gastric carcinomas through inactivation of Chk1.

Ca2 -activated K Currents of Pancreatic Duct Cells in Guinea-pig

There are numerous studies on transepithelial transports in duct cells including Cl and/or HCO3. However, studies on transepithelial K transport of normal duct cells in exocrine glands are scarce. In the present study, we examined the characteristics of K currents in single duct cells isolated from guinea pig pancreas, using a whole-cell patch clamp technique. Both Cl and K conductance were found with KCl rich pipette solutions. When the bath solution was changed to low Cl, reversal potentials shifted to the negative side, 75 4 mV, suggesting that this current is dominantly selective to K. We then characterized this outward rectifying K current and examined its Ca2 dependency. The K currents were activated by intracellular Ca2. 100 nM or 500 nM Ca2 in pipette significantly (P< 0.05) increased outward currents (currents were normalized, 76.8 7.9 pA, n=4 or 107.9 35.5 pA, n=6) at 100 mV membrane potential, compared to those with 0 nM Ca2 in pipette (27.8 3.7 pA, n=6). We next examined whether this K current, recorded with 100 nM Ca2 in pipette, was inhibited by various inhibitors, including Ba2, TEA and iberiotoxin. The currents were inhibited by 40.4 % (n=3), 87.0 % (n=5) and 82.5 % (n=9) by 1 mM Ba2, 5 mM TEA and 100 nM iberiotoxin, respectively. Particularly, an almost complete inhibition of the current by 100 nM iberiotoxin further confirmed that this current was activated by intracellular Ca2. The K current may play a role in secretory process, since recycling of K is critical for the initiation and sustaining of Cl or HCO3 secretion in these cells.

A Single Nucleotide Polymorphism in the E-cadherin Gene Promoter-160 is Not Associated with Risk of Korean Gastric Cancer

Recently, the -160 C/A polymorphism, located within the regulatory region of E-cadherin promoter, has been shown to influence E-cadherin transcription by altering transcription factor binding. We examined the effect of this polymorphism on risk of gastric cancer and on histological classification of intestinal- and diffuse-type gastric cancer in 146 normal healthy individuals and 292 Korean gastric cancer patients. Genomic DNA samples were examined by polymerase chain reaction (PCR)-single strand conformational polymorphism (SSCP)-sequencing and confirmed by restriction fragment length polymorphism (RFLP). Unexpectedly, there was no significant difference in the genotype frequencies of the polymorphism between normal control and gastric cancer patients (x(2) test, p=0.433). The estimated odd ratio of C/C to A/A genotype in gastric cancer cases was 1.07 (95% confidence interval, 0.396-2.870). We also found no evidence for differences in risk for the intestinal- and diffuse-type gastric cancer. These results suggest that the -160 C/A polymorphism of the E-cadherin has no direct effect on the risk of Korean gastric cancer development and on its histological classification.

Expression Pattern of Caspase 2 in Korean Gastric Cancers

PURPOSE: Caspase 2, a member of the family of ICE-like proteases, is activated by the Fas pathway and induces apoptosis by triggering the caspase cascade. The purpose of this study was to determine whether the expression pattern of caspase 2 might be associated with gastric cancer development and if so, to determine to which pathologic parameter it is linked. MATENRIALS AND METHODS: For the construction of the gastric cancer tissue microarray, 78 paraffin-embedded tissues containing gastric cancer areas were cored 3 times and transferred to the recipient master block. The expression pattern of caspase 2 was examined on tissue microarray slides by using immunohistochemistry and was compared with pathologic parameters, including histologic type, depth of invasion, lymph node metastasis, and peritoneal dissemination. RESULTS: Caspase 2 was expressed on superficial and foveolar epithelial cells and lymphocytes in the gastric mucosa, mainly in cytoplasm. We found loss of caspase 2 expression in 41 (52.6%) of the 78 gastric cancer tissues. Statistically, histologic type and other pathologic parameters were not related with loss of caspase 2 expression. CONCLUSION: Our findings provide enough evidence that loss of caspase 2 expression may contribute to the development of Korean gastric cancer and that it might be one of the possible escape mechanisms from apoptosis in gastric cancer.

Needle Revision on Failed Filtering Blebs Using Mitomycin C

PURPOSE: To determine the success rate and complications of Mitomycin C (MMC) augmented needle revision on failed filtering blebs. METHODS: We retrospectively investigated the records of 30 patients (32 eyes) who had undergone needle revision with MMC on failed filtering blebs. A mixture of 0.02 ml of MMC (0.4 mg/ml) and 0.02 ml of 2% lidocaine (20 mg/ml) was injected subconjunctivally. 5 minutes later, needle revision was done with bented 30 gauge needle. RESULTS: The mean Intraocular pressure(IOP) decreased from 28.1+/-9.4 mm Hg before surgery to 14.7+/-6.2 mmHg at the last follow-up. The mean follow-up period after the last needle revision was 23.5+/-19.4 months. In 27 eyes (84.4%), the last IOP was less than or equal to 18 mmHg. Serious complications were not found. CONCLUSIONS: MMC augmented needle revision appears to be an effective way to revive failed filtration blebs. The incidence of complications compares favorably to that of other glaucoma related surgery.

Surgical Outcome and Complications of Preoperative Subconjunctival Injection of Mitomycin C in Filtering Surgery

PURPOSE: We conducted a retrospective study to evaluate preoperative subconjunctival injection of mitomycin C (MMC) for surgical outcome and postoperative complications in trabeculectomy. METHODS: Twenty-eight eyes (22 patients) with glaucoma patients who were followed up for at least 6 months were injected subconjunctivally with 0.02 ml of 0.4mg/ml MMC (0.008 mg) mixed with 0.03 ml of 2% lidocaine before making the conjunctival incision and then trabeculectomy was performed after 5 minutes. RESULTS: Postoperative mean follow-up period was 21.1 months, preoperative mean IOP was 33.9 mmHg. Postoperative mean IOP at 1, 3, 6, 12month, and at the last follow-up were 9.0, 9.3, 9.5, 11.0, and 11.2 mmHg, respectively. There were statistically significant decreases of IOP in postoperation compared preoperation. When postoperative IOP were controlled below 21 mmHg and reduced under 30% compared with preoperative IOP, postoperative success rate at 1, 3, 6, 12 month, and at the last follow-up were 100%, 96%, 89%, 89%, and 86%, respectively. Postoperative complications were avascular cystic bleb in 8 eyes (29%), transient hypotony in 6 eyes (21%), shallow anterior chamber in 5 eyes (18%). Early aqueous leaking from conjunctival wound was in 4 eyes (14%). CONCLUSIONS: It is suggested that the preoperative subconjunctival injection of MMC of high concentration be used in filtering surgery. But the determination of volume and concentration is needed to prevent postoperative complications and long-term IOP lowering effect.

Frontalis Suspension Using Silicone Rod

PURPOSE: To evaluate the surgical results and complications in patients with blepharoptosis who underwent frontalis suspension using a silicone rod. METHODS: A total of 31 lids of 23 patients with blepharoptosis and poor levator function underwent a pentagon-shaped loop silicone sling surgery in which six skin incisions were made. Eighteen patients had congenital ptosis, two blepharophimosis-ptosis syndrome, two blepharoptosis with superior rectus muscle weakness, and one third nerve palsy. RESULTS: With a mean age of 14 years and a mean follow-up of 16 months, good-to-excellent lid height was achieved in 27 lids (87%) of 20 patients and poor results with undercorrection in 4 lids (13%) of 3 patients. Three of the 4 lids with poor results had reoperation and satisfactory results were achieved. Transient exposure keratitis occurred postoperatively in 7 lids (23%) and persistent exposure keratitis in 2 lids (6%). During the follow-up period, extrusion of the sling and infection did not occur; ptosis recurred in 4 lids (13%). CONCLUSIONS: Silicone rod can be adjusted easily after frontalis suspension, but it needs to pay close attention because the string can be broken during the operation or follow-up period. It is considered that additional follow-ups for a long-term recurrence rate of ptosis are necessary and sufficient explanation to the patients and family and their understanding are need.

Effect of Superior Oblique Tuck Surgery in the Patients with Unilateral Superior Oblique Palsy

This study was conducted to assess the amount of superior oblique tuck surgery and the corrected amount of vertical strabismus and head tilt after superior oblique tuck surgery in patients with unilateral superior oblique palsy.Superior oblique tuck surgery was performed on 13 patients with unilateral superior oblique palsy, which corresponded to the second or the third type with hypertropia of 25 PD (prism diopters)or less of Knapp classification. The mean preoperative vertical deviation was 17.8 PD and the mean postoperative vertical deviation was 8.8 PD:the mean corrected amount of vertical deviation was 9.0 PD.Head tilt, which had been observed in 10 (77%)patients preoperatively, improved by over 5 degrees, head tilt in 5 (50%)of them postoperatively.The results suggest that superior oblique tuck surgery may as well be combined with ipsilat eral inferior oblique weakening or with ipsilateral or contralateral vertical rectus muscle surgery in unilateral superior oblique palsy patients with the amount of vertical deviation of 15 PD or more.

A Case of Rhino-orbital Mucormycosis, Treated with Intraconal Amphotericin B Irriation and Abscess Drainage

Mucormycosis is a relatively uncommon opportunistic fungal infection that occurs more commonly in patients with immunosuppression and diabets mellitus, particularly those with ketoacidosis. Successful therapy for rhinoorbital mucormycosis requires early diagnosis, correction of predisposing conditions, prompt use of amphotericin B, and aggressive surgical debridement. We experienced a 56-years-old poorly controlled diabetic woman with rhinoorbital mucormycosis that was successfully treated with intraconal amphotericin B irrigation and packing without exenteration.

The Effect of Topical Antiglaucomatous Medication on the Outcome of Trabeculectomy

The purpose of this study was to determine whether preoperative topical antiglaucomatous therapy influences the outcome of subsequent trabeculectomy. We investigated 50 eyes of 36 patients with primary open anlge glaucoma(POAG)and 86 eyes of 77 patients with primary angle closure glaucoma (PACG), who had undergone trabeculectomy. All the patients had received topical antiglaucomatous therapy preoperatively and had been followed up for at least 6 months postoperatively. Both groups, POAG and PACG were divided into two subgroups according to the duration of preoperative antiglaucomatous therapy: (a)for less than 1 month and (b)for more than 6 months. The criterion for success was maintenance of postoperative intraocular pressure(IOP)below 21 mmHg without medication. The rates of success were compared at 1 week, 1 month, 3 months, and 6 months postoperatively. In POAG patients, the overall success rate was clinically significantly higher in subgroup (a)than in subgroup (b)(P<0.05). The success rate in subgroup (a)of POAG patients remained higher irrespective of class of antiglaucomatous medications(P<0.05). In PACG patients, the success rate was also higher in subgroup A, but it failed to reach clinical significance. Postoperative mean IOP was slightly lower in subgroup (a)of all the participants, but it was not clinically significant. Our study suggests that long-term use topical antiglaucoma medications can affect adversely the result of filtering surgery in POAG.

Comparison of Surgical Results Between Bilateral Rectus Muscle Recession and Lateral Rectus Muscle Recession and Medial Rectus Muscle Resection in Exotropia Over 40 Prism Diopters

It is the purpose of this study to compare the postoperative results of 168 patients with exotropia of basic and simulated divergence excess type over 40 prism diopters; 86 patients had bilateral rectus muscle recessions and 82 patients underwent lateral rectus muscle recession and medial rectus muscle resection. The patients in the former group had averaged 13.7 years of age and 8.2 months of postoperative follow-up period. Those in the latter group averaged 22.9 years and had been followed up for 7.1 months. The postoperative success rates are as follows: 66.7%(57/86) in the bilateral rectus muscle recession group and 68.1%(58/82) in the lateral rectus muscle recession and medial rectus muscle resection group(P>0.05). And the success rates of those older than 16 years without amblyopia are 60.0%(18/30) in the former group and 75.0%(24/32) in the latter group(P>0.05). The lateral rectus muscle recession and medial rectus muscle resection group showed somewhat higher rates of success even though it proved statistically insignificant.

Scanning Electron Microscopic Observation on the Microvasculature in Anterior Segment of the Rabbit Eye Injected with Endothelin-1

Using Mercox CL-2B, intravascular casting was performed follwoing intracameral injection with 2.0microgram/microliter of Endothelin-1(ET-1) in the rabbit eye. One hour after intracameral injection with ET-1 caused severe focal andsegmental constriction of major arterial circle(MAC). Obstruction of the small branch of MAC caused localized filling defect and decreased number of capillaries in the vascular cast. The diameters of vascular cast were reduced at about 22.2% in proximal MAC, 22.4% in distal MAC and 21.8% in first branch of MAC. This results were suggested that ET-1 may play a role in the regulation of blood flow in the anterior segment vasculature of the rabbit.

Comparison of Astigmatism According to Incision Location in 3.2mm Scleral Tunnel Incision Cataract Surgery

To evaluate surgically induced astigmatism for 6 months following 3.2mm scleral tunnel incision cataract surgery according to incision site we divided 115 patients(124 eyes) into superior incision group 1 (58 eyes) and superotemporal incision group 2 (66 eyes). Each group was classified into 3 cases according to preoperative astigmatism. Postoperative astigmatic changes by vector method were 0.40 diopter(D) against-the-rule astigmatism(ATR) in group 1, 0.25 D ART in group 2 at 6 months and there was no difference between two groups(P>0.05). In the preoperative with-the-rule astigmatic cases, postoperative astigmatic changes were 0.56 D ART in group 1, 0.38 D ATR in group 2, in the preoperative against-the-rule astigmatic cases, postoperative astigmatic changes were 0.25 D ART in group 1, 0.12 D ART in group 2, in the preoperative no astigmatic cases, postoperative astigmatism changes were 0.53 D ATR in group 1, 0.25D ART in group 2 at 6 months. There was no significant difference between two groups in postoperative astigmatic changes(P>0.05) and corneal astigmatisms were stabilized after 2 months postoperatively in both groups(P<0.05).

Surgical Result of Unilateral Medial Retus Recession and Lateral Retus Resection in Esotropia

To determine the effectiveness of unilateral medical rectus recession and lateral rectus resection in esotropia, surgical outcome was reviewed. We excluded paralytic strabismus, refractive esotropia and nonrefractive esotropia with high AC/A. Of 128 cases, 60 cases were male, 68 cases were female. At the amount of surgery, age distribution was from 11 month to 55 years. Preoperative angle of deviation was from 12 delta to 95 delta. We treated the patients with varying amount of unilateral medial rectus recession from 2.5mm to 8mm and unilateral lateral rectus resection from 2.5mm to 10mm. Following 31 months in average, 102(79.69%) showed successful alignment(orthporia +/-10 delta). The average amount of correction amount was 30.42 delta.

Surgical Result of Unilateral Medial Retus Recession and Lateral Retus Resection in Esotropia

To determine the effectiveness of unilateral medical rectus recession and lateral rectus resection in esotropia, surgical outcome was reviewed. We excluded paralytic strabismus, refractive esotropia and nonrefractive esotropia with high AC/A. Of 128 cases, 60 cases were male, 68 cases were female. At the amount of surgery, age distribution was from 11 month to 55 years. Preoperative angle of deviation was from 12 delta to 95 delta. We treated the patients with varying amount of unilateral medial rectus recession from 2.5mm to 8mm and unilateral lateral rectus resection from 2.5mm to 10mm. Following 31 months in average, 102(79.69%) showed successful alignment(orthporia +/-10 delta). The average amount of correction amount was 30.42 delta.

A Case of Bilateral Congenital Arteriovenous Communication

Congenital arteriovenous(AV) communications of retinal circulation are rare developmental anomalies, exsisting alone or in association with ipsilateral vascular anomalies of the mid brain, cranial sinuses and skin. These are usually unilateral. We report a case of bilateral congenital arteriovenous communication. The right eye showed group III arteriovenous communication of retina with vitreous hemorrhage. The left eye showed group II arteriovenous communication combined with group I.

The effect of exogenous electric currents on cyclic nucleotides in feline alveolar bone / 대한치과교정학회지

There are evidences that exogenous electric currents are capable of enhancing bone formation and resorption, and that the conversion of the bioelectric response to biochemical activity provides the directional component of orthodontic tooth movement. In addition, evidence has implicated cyclic nucleotides in alveolar bone cellular activation mechanism during orthodontic tooth movement. In view of these evidences, this study was performed to investigate the effects of exogenous electric currents in cyclic nuclotide levels in feline alveolar bone and the possible clinical applicaiton of electric currents as an additional orthodontic tool. In the first study, three groups of three adult cats were subjected to application of a constant direct current of 10+/-2 microamperes to gingival tissue near maxillary canine noninvasively for 1,3, and 7 days respectively. In the second study, three groups of three adult cats each were treated by an electric-orthodontic procedure for 1, 3, and 7 days respectively. The left maxillary (control) canine received an orthodontic force of 80gm alone at time of initiation, while the right maxillary (experimental) canine received combined force-electric stimulation (80gm of force and 10+/-2 microamperes of a constant D.C currents). Alveolar bone samples were obtained from the mesial (tension and / or cathode) and the distal (compression and/ or anode) sites surriunding maxillary canines as well as from contralateral control sites. The samples were extracted, boiled, homogenized, and the supernatants were assayed for cyclic nucleotides (cAMP, cGMP) by a radiommunoassay method. And also the amount of tooth movement was measured in the second study. On the basis of this study, the following conclusions can be drawn: 1. The fluctuation pattern of cyclic nucleotide levels in alveolar bone treated by exogenous electric currents was similar to that treated by orthodontic force. 2. The cAMP levels in alveolar bone of electrically treated teeth significantly elevated above the control values. And of electrically treated teeth, the values of the anode sites were higher than those of the cathode sites. 3. The cGMP levels in alveolar bone of electrically teeth elevated above the control values at the initation phase of treatment, but dropped below the control values at time of termination. And of electrically treated teeth, the values of the cathode sites were higher than those of the anode sites. 4. The rate of tooth movement in teeth treated by force-electric combination increased with the length of treatment as compared to that treated by mechanical force alone.

Calcium and phosphorous distributions in the alveolar bone of orthodontically treated cats / 대한치과교정학회지

This experiment was performed to investigate the response of inorganic substances in alveolar bone in relation to the experimental tooth movement. Right canine in maxillary jaw was tipped in cats by coil springs generating 80 gm. force, in mandibular jaw, the force was 100 gm. force. Cats were divided into five groups and orthodontically treated for one hour, 1, 7, 14 and 28 days, respectively. Alveolar bone samples were obtained from tension and compression sites as well as from contralateral control sites. The level of calcium of alveolar bone was determined by atomic absorption spectrophotometry and inorganic phosphorus was measured by spectrophotometry. The results obtained were-as follows: 1. In tension and compression site of maxillary alveolar bone, calcium levels were decreased at 1, 7 and 14 days, but recovered at 28 days. 2. The levels of inorganic phosphorus in compression site of maxillary alveolar bone had little change but in tension site of maxillary alveolar bone,, phosphorous levels were decreased. 3. Calcium levels in tension and compression site of mandibular alveolar bone were decreased, especially at 28 days. 4. In tension and compression site of mandibular alveolar bone, inorganic phosphorus were slightly decreased from I day.

A study on cyclic AMP in alveolar bone treated by orthodontic forces / 대한치과교정학회지

Tooth movement by orthodontic force is based upon alveolar bone resorption at compression site and bone formation at tension site of tooth. The function of cyclic AMP is to participate not only in initial action of bone cells by mechanical forces but also in the continuous cellular response leading, to bone remodeling. This experiment was performed to clarify the role of cyclic AMP in bone remodeling by mechanical forces. The orthodontic forces of about 80 gm and 100 gm were applied to the right canines of maxillary and mandibular bone, respectively, in cats, treated for periods of time ranging from one hour to 28 days. Alveolar bones were obtained from compression and tension sites . surrounding tipping maxillary and mandibular canines as well as from contralateral control sites. The samples were extracted, boiled and homogenized, and the supernatants were assayed for cyclic AMP by a radioimmunoassay mothod. The results were as follows: 1. The orthodontic movement of canines was increased to the end of experimental period and the action of orthodontic forces on tooth movement was more effective in maxillary canine. 2. The cyclic AMP levels of alveolar bones in compression and tension sites initially decreased, then increased and remained elevated to the end of experiment. The differences of the cyclic AMP levels between treated sites and non-treated sites were gradually increased. 3. The cyclic AMP levels in treated sites of mandibular alveolar bone was higher than that of maxillary alveolar bone.