Comparative study of Helicobacter pylori eradication rates of twice-versus four-times-daily amoxicillin administered with proton pump inhibitor and clarithromycin: a randomized study

BACKGROUND

Proton pump inhibitor (PPI)-containing triple therapy with clarithromycin and amoxicillin is now a standard regimen for Helicobacter pylori eradication in Korea. Amoxicillin has time-dependent bactericidal activity against H. pylori; we therefore assumed a dosing schedule of amoxicillin would affect the eradication rate of H. pylori. The purpose of this study was to evaluate and compare the efficacy of different amoxicillin dosing schedules for the eradication of H. pylori.

MATERIALS AND METHODS

One hundred and eighty-six patients with H. pylori infection were eligible for this study. Patients were randomly assigned to one of two regimens: amoxicillin 1000 mg with clarithromycin 500 mg and omeprazole 20 mg twice daily for 2 weeks (BID group, n = 93), or amoxicillin 500 mg four times daily with clarithromycin 500 mg and omeprazole 20 mg twice daily for 2 weeks (QID group, n = 93). The success of H. pylori eradication was evaluated 4-5 weeks after completing treatment.

RESULTS

Overall eradication rate was 90.3%, and eradication rates were 91.4% in the BID group and 89.2% in the QID group (p = 0.62). Compliances was 95.7% in the BID group and 93.5% in the QID group (p = 0.516); this was the only factor that significantly affected H. pylori eradication in this study. Side effects in both groups were generally mild.

CONCLUSIONS

Amoxicillin regimens with PPI and clarithromycin are found to be equally effective and safe in both the BID and QID groups for H. pylori eradication. Therefore, considering patient's comfort, we recommend a twice daily amoxicillin regimen.

[Analysis of the factors that affect the mortality rate in severe acute pancreatitis]

BACKGROUND/AIMS

Severe acute pancreatitis occurs in about 20% of the patients with acute pancreatitis and can be associated with multiorgan failure and local complications. In patients with predicted severe acute pancreatitis, overall mortality rates are about 15-30%. The aim of this study was to determine the factors correlated with mortality in patients with severe acute pancreatitis.

METHODS

We reviewed five hundread and seventy two consecutive cases of acute pancreatitis from January, 2000 to December, 2005. Of them, 109 patients who fulfilled the criteria of Atlanta classification for severe acute pancreatitis were enrolled. Data were collected by chart reviews including age, gender, etiology, body mass index (BMI), modified Glasgow score, APACHE II score, APACHE III score, Balthazar CT index, and other laboratory parameters performed within 48 hours after the initial admission.

RESULTS

Severe acute pancreatitis was most commonly caused by alcohol. Overall mortality rate was 20.2% in severe acute pancreatitis and 10 (45%) deaths occurred within the first week. Multiple logistic regression analysis identified serum creatinine, corrected calcium concentrations, and CT index as predictors of mortality in patients with severe acute pancreatitis. The risk score (R) was calculated by combining 3 prognostic values with regression coefficients; R=2.512 loge (creatinine mg/dL)+1.729 loge (CT index)??4.780 loge (corrected calcium mg/dL). The AUC for this score was 0.877 and a cutoff level of 0 was determined to predict the mortality with 83.3% sensitivity and 89.5% specificity.

CONCLUSIONS

The newly designed risk score comprising 3 parameters can be used as the significant early predictor for hospital mortality in severe acute pancreatitis.

Expression of N-methyl-d-aspartate receptor 1 in rats with chronic ocular hypertension

High levels of glutamate can be toxic to retinal ganglion cells (RGCs). This study investigated the relationship between the N-methyl-d-aspartate receptor 1 (NR) and RGC death in a rat model of chronic ocular hypertension (COHT). COHT was induced in one eye of each rat by episcleral vein cauterization. Retinal protein expression was evaluated at 1, 3, 5 and 9 weeks after cauterization. Quantitative real-time polymerase chain reaction and Western blot analysis showed that NR1 expression was significantly increased in cauterized retinae. NR1 immunoreactivity was observed in the inner nuclear layer (INL) and ganglion cell layer (GCL) in the retina of rats with COHT. RGC density was evaluated after retrograde labeling with fluoro-gold (FG) and 4-di-10-ASP (DiA). A significant decrease in RGC density was observed in ocular hypertensive eyes, and NR1 expression in the GCL suggested an important role of NR1 in the death of RGCs. Memantine (10 mg/kg), an N-methyl-d-aspartate receptor antagonist, was administered orally once daily for up to 5 weeks, while rats in the control group received vehicle phosphate-buffered saline only. Treatment with memantine resulted in a significant reduction in RGC loss and NR1 expression in the eyes of rats COHT. These findings suggest that excessive expression of NR1 is involved in RGC death in glaucoma.

Limits on interactions between weakly interacting massive particles and nucleons obtained with CsI(Tl) crystal detectors

The Korea Invisible Mass Search (KIMS) experiment presents new limits on the weakly interacting massive particle (WIMP)-nucleon cross section using data from an exposure of 3409 kg.d taken with low-background CsI(Tl) crystals at the Yangyang Underground Laboratory. The most stringent limit on the spin-dependent interaction for a pure proton case is obtained. The DAMA signal region for both spin-independent and spin-dependent interactions for the WIMP masses greater than 20 GeV/c2 is excluded by the single experiment with crystal scintillators.

[Comparison of CTP, MELD, and MELD-Na scores for predicting short term mortality in patients with liver cirrhosis]

BACKGROUND/AIMS

MELD-Na (model for end-stage liver disease with incorporation of serum sodium) was suggested to provide better survival prediction than MELD alone for patients with end stage liver disease. However, there is no data verifying the usefulness of MELD-Na for predicting short term mortality of cirrhotic patients in Korea. This study was aimed to determine whether MELD-Na would be more accurate in predicting short term mortality than other scoring systems such as Child-Turcotte-Pugh (CTP) or MELD.

METHODS

Data from 355 patients admitted due to liver cirrhosis were retrospectively reviewed. The cumulative survival rates were obtained. Prediction of mortality rate for three months and one year were analyzed using the area under the receiver's operating characteristics curve (AUC).

RESULTS

One hundred patients (28%) died during the study period. All of the three systems showed significant differences in the cumulative survival rate according to the scores on admission (p0.001). The AUC of CTP, MELD, and MELD-Na in predicting three-months mortality were 0.828, 0.845, and 0.862 (p0.05), and the AUC of each score system for death within one year were 0.792, 0.800, and 0.831, respectively (p0.05). The AUC of MELD-Na in predicting short term death were the highest, although it was not statistically significant. Multivariate analysis showed that only MELD-Na was significantly related to three-month mortality (p=0.012).

CONCLUSIONS

MELD-Na is more appropriate in predicting short term mortality, but larger scale studies are needed to confirm the superiority of MELD-Na to MELD and CTP in patients with liver cirrhosis.

Pneumoretroperitoneum, pneumomediastinum, peumopericardium, and subcutaneous emphysema after colonoscopic examination

Colonoscopy is regarded as a relatively safe procedure and is widely performed. However, complications such as bleeding, perforation, and coagulation syndromes can occur during colonoscopy. Although bowel perforation is as rare as 0.4-1.9% of cases, it is the most serious and awful adverse event which can lead to a death. Colon perforation may occur as either intraperitoneal or extraperitoneal, or in combination. Right subdiaphragmatic free air suggests intraperitoneal perforation while pneumoretroperitoneum, pneumomediastinum, pneumopericardium, and subcutaneous emphysema suggest extraperitoneal perforation. Combined intraperitoneal and extraperitoneal perforation is very rare. Herein, we present a case of combined intraperitoneal and extraperitoneal colon perforation which manifested as pneumoretroperitoneum, pneumomediastinum, pneumopericardium, and subcutaneous emphysema. The lesion was closed with endoscopic clipping.

Endoscopic removal of biliary self-expandable metallic stents: a prospective study

BACKGROUND AND STUDY AIMS

The transpapillary endoscopic insertion of self-expandable metallic stents (SEMSs) has been widely used for the palliation of unresectable malignant biliary obstruction. We attempted the endoscopic removal of malfunctioning SEMSs. The aim of this study was to assess the feasibility and safety of the endoscopic removal of SEMSs by comparing the results between removal of covered and uncovered SEMSs.

PATIENTS AND METHODS

30 patients with a malfunctioning biliary SEMS prospectively underwent an attempt at endoscopic removal of the biliary SEMS over a 2-year period. Removal of the malfunctioning SEMS was done with a therapeutic duodenoscope (ED-450XT5 or TJF-240), using a rat-tooth forceps. Of the 30 SEMS used, 22 were silicone-covered Wallstents, while eight were uncovered SEMSs including five uncovered Wallstents and three Zilver stents. The time for an attempt at each endoscopic removal was limited to 15 minutes in a single endoscopic procedure session.

RESULTS

The covered SEMSs were easily removed in 19 out of 22 patients (86.4 %), whereas none of the eight uncovered SEMSs (0 %) could be removed. The only factor predicting successful stent removal was the presence of a stent covering ( P = 0.000). There was no morbidity or mortality related to endoscopic removal of malfunctioning stents.

CONCLUSIONS

In contrast to uncovered biliary SEMSs, in most cases malfunctioning covered biliary SEMSs can be easily and safely removed endoscopically using a rat-tooth forceps.

Endoscopic removal of biliary self-expandable metallic stents: a prospective study

BACKGROUND AND STUDY AIMS

The transpapillary endoscopic insertion of self-expandable metallic stents (SEMSs) has been widely used for the palliation of unresectable malignant biliary obstruction. We attempted the endoscopic removal of malfunctioning SEMSs. The aim of this study was to assess the feasibility and safety of the endoscopic removal of SEMSs by comparing the results between removal of covered and uncovered SEMSs.

PATIENTS AND METHODS

30 patients with a malfunctioning biliary SEMS prospectively underwent an attempt at endoscopic removal of the biliary SEMS over a 2-year period. Removal of the malfunctioning SEMS was done with a therapeutic duodenoscope (ED-450XT5 or TJF-240), using a rat-tooth forceps. Of the 30 SEMS used, 22 were silicone-covered Wallstents, while eight were uncovered SEMSs including five uncovered Wallstents and three Zilver stents. The time for an attempt at each endoscopic removal was limited to 15 minutes in a single endoscopic procedure session.

RESULTS

The covered SEMSs were easily removed in 19 out of 22 patients (86.4 %), whereas none of the eight uncovered SEMSs (0 %) could be removed. The only factor predicting successful stent removal was the presence of a stent covering ( P = 0.000). There was no morbidity or mortality related to endoscopic removal of malfunctioning stents.

CONCLUSIONS

In contrast to uncovered biliary SEMSs, in most cases malfunctioning covered biliary SEMSs can be easily and safely removed endoscopically using a rat-tooth forceps.

Dielectrophoretic alignment of gallium nitride nanowires (GaN NWs) for use in device applications

We report on a simple and effective ac and dc dielectrophoresis (DEP) method that can be used to align and manipulate semiconductor gallium nitride (GaN) nanowires (NWs) with variations in the type of electrical fields as well as variations of frequency. We observed that the ability of the alignment and the formation of the assembling nanowires (single or a bundle configuration) strongly depend on the magnitude of both the ac and dc electric fields. The yield results indicate that the GaN NWs, using ac DEP, are better aligned with a higher yield rate of approximately 80% over the entire array in the chip than by using dc DEP. In addition, we first demonstrated the simple hybrid p-n junction structures assembled by n-type GaN nanowires together with a p-type silicon substrate (n-GaN NW/p-Si substrate) using dielectrophoresis. From the transport measurements, the p-n junction structures show well-defined current rectifying behaviour with a low reverse leakage current of approximately 3 x 10(-4) A at -25 V. We believe that our unique p-n junction structures can be useful for electronic and optoelectronic nanodevices such as rectifiers and UV nano-LEDs.

[A case of peripheral ischemic complication after terlipressin therapy]

Hepatorenal syndrome is a severe complication of cirrhosis, leading to death in more than 90% of cases in the absence of liver transplantation. Several treatments have been attempted as a bridge to liver transplantation. Among such treatments, terlipressin is a nonselective V1 vasopressin agonist. When comparing with ornipressin, it is known to have a similar vasoconstricting potency, but much less ischemic complication. We report a case of gangrene on toes and necrosis on the infusion site of left hand which developed after the use of terlipressin due to hepatorenal syndrome in a 41-year-old-man with liver cirrhosis. Ischemic complication of terlipressin is rare and there has been no case report in Korea. Although it is rare, we must pay attention to the peripheral ischemic complication of terlipressin.

[Comparison of the effectiveness of quadruple salvage regimen for Helicobacter pylori infection according to the duration of treatment]

BACKGROUND/AIMS

At present, triple therapy schemes are recommended by national and international consensus conferences for the treatment of Helicobacter pylori (H. pylori) infection. However, even with the most effective current treatment regimens, about 10-20% of patients fail to eradicate H. pylori, necessitating alternative strategy to eradicate H. pylori in primary treatment failure. Therefore, we performed this study to evaluate the efficacy of quadruple therapy and to compare 1 and 2-week quadruple regimen as a second-line therapy.

METHODS

The hospital records of 155 patients who failed to the standard triple therapy (proton pump inhibitor, amoxicillin, clarithromycin) were reviewed retrospectively, and divided the 1 or 2 weeks OBMT regimen (omeprazole 20 mg bid, bismuth salt 120 mg qid, metronidazole 500 mg tid, tetracycline 500 mg qid). Presence of H. pylori infection and side-effects of the treatment regimen were assessed 4 weeks after the cessation of treatment.

RESULTS

One hundred and eight male and 47 female (mean age, 52.2+/-15.4) patients were enrolled. The overall eradication rate of H. pylori with quadruple therapy was 83.9% and the eradication rate was similar between 1 and 2 weeks of OBMT regimen (76.8% in OBMT 1 week, 87.9% in OBMT 2 weeks, respectively p=0.110).

CONCLUSIONS

Quadruple therapy is an effective salvage regimen for H. pylori eradication after the failure of standard triple therapy. One week quadruple therapy is not significantly different from 2-weeks regimen as the second-line option for H. pylori eradication.

[Survival analysis according to treatment modality in pancreatic cancer patient]

BACKGROUND/AIMS

Pancreatic cancer is the 5(th) leading cause of cancer death in Korea and its incidence is increasing. At present, surgical resection offers the best chance of cure. However, most of pancreatic cancers are already unresectable at initial diagnosis. Thus, the majority of patients depend on chemotherapy, radiotherapy, or supportive care. We investigated the effect of treatment modalities on the survival in pancreatic cancer.

METHODS

Between September 1994 and May 2003, one hundred and fifty four patients with pancreatic cancer were treated by surgery, radiotherapy, chemotherapy or conservative management. The clinical datas were analyzed retrospectively for survival according to stage and treatment modality.

RESULTS

Overall median survival time was 5.7 months and 1 year survival rate was 18.3%. In patients with stage I to III disease, the median survival time was 13.9 months in surgery group, 10.2 months in radiation group, and 6.1 months in supportive care group (p%lt;0.01). Survival rate according to treatment modality was significantly different among groups. In patients with stage IV disease, the median survival time was 6.1 months in radiation therapy group, 7.1 months in chemotherapy group, and 2.7 months in supportive care group. Overall survival was significantly higher in treatment groups than in supportive care group (p<0.01), but there was no difference in survival between chemotherapy group and radiotherapy group.

CONCLUSIONS

In patients with stage I to III pancreatic cancer, surgery can improve median survival. In patients with stage IV, either chemotherapy or radiotherapy can prolong survival compared to supportive care. These results suggest that more active treatment of pancreatic cancer even in advanced stage will be needed to prolong the survival.

[Efficacy of 14 day OBMT therapy as a second-line treatment for Helicobacter pylori infection]

BACKGROUND/AIMS

As a second-line treatment for H. pylori eradication in the case of first-line OAC (omeprazole, amoxicillin, clarithromycin) treatment failure, a minimum of one-week OBMT quadruple therapy composed of omeprazole, bismuth, metronidazole, tetracycline has been recommended in European countries and one or two weeks in USA. In Korea, one-week OBMT quadruple therapy is recommended for the case of first-line OAC treatment failure. Because H. pylori eradication rate of one-week OBMT therapy in Korea is about 80%, the eradication rate of one week therapy is not satisfactory. We analyzed the effect of two-week second-line OBMT therapy.

METHODS

Between June 2002 and June 2003, 107 patients who were H. pylori positive (44 males and 63 females: mean age 51.8 years) after primary eradication therapy received two-week OBMT therapy. Four weeks after completion of therapy, 13C-urea breath test was performed to detect H. pylori.

RESULTS

After two weeks of OBMT therapy, eradication was achieved in 103 of 107 patients (96.3%) and in 68 of 71 peptic ulcer patients (95.8%).

CONCLUSIONS

Two-week OBMT therapy should be considered as a retreatment regimen with the eradication rate more than 90%.

Treatment of taste and odor material by oxidation and adsorption

Massive blooms of blue-green algae in reservoirs produce the musty-earthy taste and odor, which are caused by compounds such as 2-MIB and geosmin. 2-MIB and geosmin are rarely removed by conventional water treatment. Their presence in the drinking water, even at low levels (ng/L), can be detected and it creates consumer complaints. So those concentrations have to be controlled as low as possible in the drinking water. The removals by oxidation (O3, Cl2, ClO2) and adsorption (PAC, filter/adsorber) were studied at laboratory and pilot plant (50 m3/d) to select suitable 2-MIB and geosmin treatment processes. The following conclusions were derived from the study. Both of the threshold odor levels for 2-MIB and geosmin appeared to be 30 ng/L as a consequence of a lab test. For any given PAC dosage in a jar-test, removal efficiencies of 2-MIB and geosmin were increased in proportion to PAC dosage and were independent of their initial concentration in raw water for the tested PAC dosages. In comparison of geosmin with 2-MIB, the adsorption efficiency of geosmin by PAC was superior to that of 2-MIB. The required PAC dosages to control below the threshold odor level were 30 mg/L for geosmin and 50 mg/L for 2-MIB at 100 ng/L of initial concentration. Removal efficiencies of odor materials by Cl2, ClO2, and O3 were very weak under the limited dosage (1.5 mg/L), however increased ozone dosage (3.8 mg O3/L) showed high removal efficiency (84.8% for 2-MIB) at contact time 6.4 minutes. According to the initial concentrations of 2-MIB and geosmin, their removal efficiencies by filter/adsorber differed from 25.7% to 88.4%. For all those, however, remaining concentrations of target materials in finished waters were maintained below 30 ng/L. The longer run-time given for the filter/adsorber, the higher the effluent concentration generated. So it is necessary that the run-time of the filter/adsorber be decreased, when 2-MIB or geosmin occurs in raw water.

Intracranial ictal onset zone in nonlesional lateral temporal lobe epilepsy on scalp ictal EEG

OBJECTIVE

To determine the ictal focus and the role of seizure characteristics, fluorodeoxyglucose (FDG) PET, and subtraction ictal SPECT in patients diagnosed as having nonlesional lateral temporal lobe epilepsy by long-term scalp video-EEG monitoring.

METHODS

The authors studied 33 consecutive patients with nonlesional neocortical epilepsy who had a scalp ictal onset zone localized in the temporal lobe and good surgical outcome after focal neocortical resection. All patients were evaluated using intracranial recordings prior to resection. Semiology, FDG-PET, and ictal-interictal subtraction SPECT were used to verify the diagnostic role of these methods in the localization of epileptic foci.

RESULTS

The ictal onset zones, confirmed by intracranial study, were the lateral temporal (22 patients), parietal (5), frontal (3), temporoparietal (2), and occipital (1) areas. FDG-PET analyzed by statistical parametric mapping correctly localized the epileptogenic lobe in 18 of 33 patients and subtraction ictal SPECT correctly localized it in 13 of 25 patients. However, in patients with extratemporal ictal onset zones, FDG-PET and ictal SPECT in combination correctly localized the epileptogenic lobe in only 3 of 11 cases.

CONCLUSIONS

An extratemporal ictal onset zone was encountered in patients with nonlesional lateral temporal lobe seizures based on scalp video-EEG monitoring. FDG-PET and subtraction SPECT had localizing value in no more than half of patients.

Intracranial ictal onset zone in nonlesional lateral temporal lobe epilepsy on scalp ictal EEG

OBJECTIVE

To determine the ictal focus and the role of seizure characteristics, fluorodeoxyglucose (FDG) PET, and subtraction ictal SPECT in patients diagnosed as having nonlesional lateral temporal lobe epilepsy by long-term scalp video-EEG monitoring.

METHODS

The authors studied 33 consecutive patients with nonlesional neocortical epilepsy who had a scalp ictal onset zone localized in the temporal lobe and good surgical outcome after focal neocortical resection. All patients were evaluated using intracranial recordings prior to resection. Semiology, FDG-PET, and ictal-interictal subtraction SPECT were used to verify the diagnostic role of these methods in the localization of epileptic foci.

RESULTS

The ictal onset zones, confirmed by intracranial study, were the lateral temporal (22 patients), parietal (5), frontal (3), temporoparietal (2), and occipital (1) areas. FDG-PET analyzed by statistical parametric mapping correctly localized the epileptogenic lobe in 18 of 33 patients and subtraction ictal SPECT correctly localized it in 13 of 25 patients. However, in patients with extratemporal ictal onset zones, FDG-PET and ictal SPECT in combination correctly localized the epileptogenic lobe in only 3 of 11 cases.

CONCLUSIONS

An extratemporal ictal onset zone was encountered in patients with nonlesional lateral temporal lobe seizures based on scalp video-EEG monitoring. FDG-PET and subtraction SPECT had localizing value in no more than half of patients.

Vestibular diagnosis as prognostic indicator in sudden hearing loss with vertigo

The majority of episodes of sudden hearing loss are caused by inner ear disorders, often accompanied by vertigo. The patterns of hearing loss usually influence the prognosis. The purpose of this study was to analyze vestibular diagnoses in sudden hearing loss with vertigo, and to correlate them with the recovery of hearing loss. The clinical records of 125 patients with sudden hearing loss were reviewed. Various vestibular evaluations were performed in 36 patients with vertigo. The vertigo in these patients was classified as normal, unilateral hypofunction, directional preponderance, benign paroxysmal positional vertigo (BPPV), non-specific or irritative. The initial and final pure-tone audiograms of these patients were compared. The distribution of vestibular diagnoses was unilateral hypofunction in 30.6% of patients, BPPV in 25.7%, normal in 19.4%, non-specific in 11.1%, directional preponderance in 8.3% and irritative in 8.3%. The recovery of hearing in patients with vertigo was significantly worse than in those without vertigo. The recovery of hearing in patients with spinning vertigo did not differ from that of patients with non-spinning vertigo. The recovery of hearing was worst in the BPPV group, especially in the high frequency range, followed by the unilateral hypofunction group, who showed hearing thresholds between those in the BPPV group and those in the normal vestibular function test group. This study suggests that the diagnostic classification of vestibulopathy is a useful prognostic indicator of hearing recovery in sudden hearing loss with vertigo. We conclude that otolithic and semicircular canal involvement may cause poor hearing results, especially in the high frequency range.

Effect of allergina on mast cell-mediated allergic reactions

The herbal formulation ALLERGINA has been used against allergic inflammation disease for generations, and still occupies an important place in traditional medicine in Korea. In this study, we investigated the effect of ALLERGINA by oral administration in mast cell-mediated anaphylaxis responses. ALLERGINA dose-dependently inhibited compound 48/48-induced systemic anaphylaxis with doses of 10(-2) to 5 g/kg 1 h before orally administered. Of special note, ALLERGINA inhibited systemic anaphylaxis completely with doses of 1 g/kg and 5 g/kg. ALLERGINA (1 g/kg) also inhibited passive cutaneous anaphylaxis by 84%. ALLERGINA dose-dependently inhibited histamine release from rat peritoneal mast cells. When ALLERGINA (0.01 mg/ ml) was added, ALLERGINA inhibited the production of tumor necrosis factor-alpha and interleukin-6, 80% and 26%, respectively in anti-dinitrophenyl IgE antibody-stimulated mast cells. Our studies provide evidence that ALLERGINA may be beneficial in the treatment of allergic inflammation diseases.

A triterpene glucosyl ester from the roots of Rubus crataegifolius

Along with five known triterpene glycosides, a new triterpene glucosyl ester, named crataegioside, was isolated from the roots of Rubus crataegifolius Bunge. The structure was established as ilexosapogenin A 28-O-beta-D-glucopyranosyl ester by chemical and spectroscopic methods.

Sinonasal tuberculosis associated with osteomyelitis of the ethmoid bone and cervical lymphadenopathy

Sinonasal tuberculosis is a rare disease; its association with osteomyelitis of surrounding bone and cervical lymphadenopathy has been reported rarely. In this article, we report a case of sinonasal tuberculosis that was complicated by osteomyelitis of the ethmoid bone and cervical lymphadenopathy. Infection of the bone was demonstrated by biopsy and (99m)Tc-MDP bone single photon emission computed tomography (SPECT), and cervical lymphadenopathy was confirmed by histology. This case will be discussed with specific emphasis on the imaging characteristics.

A Case of Primary MALT Lymphoma of the Breast

Primary malignant lymphoma of the breast is rare. The incidence of primary malignant lymphomas of the breast is 0.04% to 0.5% of all malignant tumors of the breast and 0.07% of all non-Hodgkin's lymphomas, and comprises 1.7% of extranodal malignant lymphomas that occur in Western countries. The incidence of mucosa- associated lymphoid tissue (MALT) lymphoma of the breast is reported to be between 0% and 75% of all primary malignant breast lymphomas in United States and Japan, but the incidence in Korea is unknown. MALT is characterized by indolent behavior and good has a prognosis. The authors report on a patient who has a primary MALT lymphoma of the breast. She was treated by surgical excision, which was followed by radiation therapy. Histologically, her lymphoma type transformed into a diffuse large B-cell tumor after 10months. She received combination chemotherapy and achieved a complete state of remission. She then underwent autologous peripheral blood stem cell transplantation along with high dose chemotherapy. To our knowledge, this is the first case report in the literature in Korea.

Novel transglutaminase inhibitors reduce the cornified cell envelope formation

Transglutaminase (TGase) is a calcium-dependent enzyme which catalyzes the iso-peptide cross-link between peptide-bound glutamine and lysine in vivo. Though the cross-link is developed as a barrier function in the skin system, overexpression of this could invoke skin hyperkeratosis in psoriasis and roughness in aged skin. In former research, many strong irreversible TGase inhibitors failed application because of high cytotoxicity. We selected one peptide after primary screening of six synthetic peptides designed from domains of known TGase substrates. Then we attempted to reduce the size and finally obtained two tetrameric peptides. When we treated keratinocyte with these TGase inhibitors under calcium-induced differentiation, the formation of a cornified cell envelope (CE) was decreased to the same level of CE under proliferating conditions without cytotoxic effect. Therefore, we propose that these TGase inhibitors may be useful for solving the physiological hypercross-linking problems for pharmaceutical or cosmetic purposes.

Optical implementation of the Hopfield model for two-dimensional associative memory

Optical implementation of Hopfield's neural network model [Proc. Natl. Acad. Sci. USA 79, 2554 (1982)] for two-dimensional associative memory is discussed. Two-state neuron elements are represented by a twisted nematic liquid-crystal optical switch array, and three-dimensional holographic interconnections are realized with these elements. Unipolar connections, created by adding a constant to bipolar interconnections and compensating them with an input-dependent thresholding operation, are realized. The 16- (4 x 4) neuron system model acts as a content-addressable associative memory with error-correction capability.