Development of a PMMA phantom as a practical alternative for quality control of gamma knife® dosimetry

BACKGROUND

To measure the absorbed dose rate to water and penumbra of a Gamma Knife® (GK) using a polymethyl metacrylate (PMMA) phantom.

METHODS

A multi-purpose PMMA phantom was developed to measure the absorbed dose rate to water and the dose distribution of a GK. The phantom consists of a hemispherical outer phantom, one exchangeable cylindrical chamber-hosting inner phantom, and two film-hosting inner phantoms. The radius of the phantom was determined considering the electron density of the PMMA such that it corresponds to 8 g/cm2 water depth, which is the reference depth of the absorbed dose measurement of GK. The absorbed dose rate to water was measured with a PTW TN31010 chamber, and the dose distributions were measured with radiochromic films at the calibration center of a patient positioning system of a GK Perfexion. A spherical water-filled phantom with the same water equivalent depth was constructed as a reference phantom. The dose rate to water and dose distributions at the center of a circular field delimited by a 16-mm collimator were measured with the PMMA phantom at six GK Perfexion sites.

RESULTS

The radius of the PMMA phantom was determined to be 6.93 cm, corresponding to equivalent water depth of 8 g/cm2. The absorbed dose rate to water was measured with the PMMA phantom, the spherical water-filled phantom and a commercial solid water phantom. The measured dose rate with the PMMA phantom was 1.2% and 1.8% higher than those measured with the spherical water-filled phantom and the solid water phantom, respectively. These differences can be explained by the scattered photon contribution of PMMA off incoming 60Co gamma-rays to the dose rate. The average full width half maximum and penumbra values measured with the PMMA phantom showed reasonable agreement with two calculated values, one at the center of the PMMA phantom (LGP6.93) and other at the center of a water sphere with a radius of 8 cm (LGP8.0) given by Leksell Gamma Plan using the TMR10 algorithm.

CONCLUSIONS

A PMMA phantom constructed in this study to measure the absorbed dose rates to water and dose distributions of a GK represents an acceptable and practical alternative for GK dosimetry considering its cost-effectiveness and ease of handling.

An effective calibration technique for radiochromic films using a single-shot dose distribution in Gamma Knife(®)

PURPOSE

A method of calibrating radiochromic films for Gamma Knife(®) (GK) dosimetry was developed. The applicability and accuracy of the new method were examined.

METHODS

The dose distribution for a sixteen millimeter single-shot from a GK was built using a reference film that was calibrated using the conventional multi-film calibration (MFC) method. Another film, the test film, from a different set of films was irradiated under the same conditions as the reference film. The calibration curve for the second set of films was obtained by assigning the dose distribution of the reference film to the optical density of the test film, point by point. To assess the accuracy of this single-film calibration (SFC) method, differences between gamma index pass rates (GIPRs) were calculated.

RESULTS

The SFC curves were successfully obtained with estimated errors of 1.46%. GIPRs obtained with the SFC method for films irradiated using a single-shot showed differences less than one percentage point when dose difference criterion (ΔD) was 2% and the distance to agreement criterion (Δd) was 1 mm. The GIPRs of the SFC method when the films were irradiated following a virtual target treatment plan were consistent with the GIPRs of the MFC method, with differences of less than 0.2 percentage points for ΔD = 1% and Δd = 1 mm.

CONCLUSION

The accuracy of the SFC method is comparable to that of conventional multi-film calibration method for GK film dosimetry.

The change of atomic distribution and hardness by nitrogen implantation into aluminum alloy

Through many studies of the nitrogen implantation into aluminum alloy, researchers have concluded that AlN (aluminum nitride) formation is the key to hardening the aluminum surface. We implanted nitrogen ions into the Al6061, using an ion implanter which has a modified Bernas ion source. We changed the incident ion energies (25 keV, 50 keV) and fluences (1x10(17)-2x10(18) ions/cm(2)). To measure the depth hardness of implanted samples, we used nanoindentation test. The test results showed that the hardness of the implanted sample increased as the incident ion fluence increased until 1x10(18) ions/cm(2). However, the hardness did not increase at the fluence of 2x10(18) ions/cm(2). Furthermore, another result showed that the hardness was slightly decreased. To see the depth distribution of elements, we used Auger electron spectroscopy (AES) analysis with depth profiling. Through the AES analysis, we observed that the nitrogen atomic ratio did not increase; since the atomic ratio reached its maximum point (50%), the depth profile formed a flat curve in the AES. It is determined by the AlN structure (1:1 combination), that is, by the stoichiometrical rule. The nitrogen atoms diffused to the inner and outer sides rather than made a narrowly ranged accumulation. We observed that the flat curve was lowered downward a little at the fluence of 2x10(18) ions/cm(2). Observing the atomic distribution of oxygen in AES, we could conclude that the lowered curve was due to the recoil implantation of oxygen which had been originally combined with the aluminum surface in the aluminum oxide (Al(2)O(3)) layer. Comparing the AES result and the nanoindention result, we concluded that the recoiled oxygen atoms are not effective on hardening the Al surface. In this study, we observed the tendency to stop increasing the samples' hardness over the ion fluence of 1x10(18) ions/cm(2). We observed the saturation of the atomic ratio by the stoichiometrical rule.

Nutrition and oral health

Reduced chewing function in community-dwelling older people with adequate general health is linked to having fewer than 20 teeth present or to wearing removable dentures. By chewing for longer periods of time or swallowing larger food particles they are normally able to compensate for the impaired function. The masticatory function can be restored by adequate prosthetic therapy, which results in increased activity of the masticatory muscles during chewing and reduces the chewing time and the number of chewing strokes until swallowing. In frail or dependent elderly people undernutrition is prevalent because of health problems, reduced appetite and poor quality of life. Poor oral health and xerostomia are often associated with a reduced body mass index and serum albumin level and the avoidance of difficult-to-chew foods. Maintenance or re-establishment of masticatory function is an integral part of the medical health care of these patients, with the aim of improving their nutritional status and quality of life.

Recurrent pyogenic cholangitis: comparison between MR cholangiography and direct cholangiography

PURPOSE

To compare the accuracy of magnetic resonance (MR) cholangiography with that of direct cholangiography for the evaluation of recurrent pyogenic cholangitis.

MATERIALS AND METHODS

Twenty-four patients with recurrent pyogenic cholangitis underwent MR cholangiography before surgery, and 18 of these 24 also underwent direct cholangiography. Two reviewers evaluated MR cholangiograms and direct cholangiograms and focused on identifying intrahepatic ductal dilatation, stricture, and calculi, as well as coexistent parenchymal abnormalities, on the basis of the classification of the internal lobes and segments of the liver. These observations were compared with surgical findings.

RESULTS

According to examination results in the surgical specimens, 24 patients had 46 segmental abnormalities. MR cholangiography depicted all 46 (100%) segments with ductal dilatation, 22 (96%) of 23 segments with focal ductal stricture, and 43 (98%) of 44 segments with ductal calculi. Eighteen patients who underwent direct cholangiography had 32 segmental abnormalities according to examination results in the surgical specimens. Direct cholangiography depicted 15 (47%) of 32 segments with ductal dilatation, eight (44%) of 18 segments with focal ductal stricture, and 14 (45%) of 31 segments with ductal calculi.

CONCLUSION

MR cholangiography is superior to direct cholangiography for accurate topographic evaluation of recurrent pyogenic cholangitis because it is able to depict all of the biliary tree, despite obstruction or stenosis.

Successful aging--the case for prosthetic therapy

Reduced chewing ability in community-dwelling older people is linked to the presence of removable dentures and having fewer than 20 natural teeth present. Compensation is provided by chewing longer and swallowing larger food particles. Replacement of posterior tooth loss by fixed or removable prostheses increases the activity of the masticatory muscles, and reduces chewing time and the number of chewing strokes until swallowing. In residents of nursing homes and long-term care facilities undernutrition is prevalent because of general medical problems, reduced appetite, and poor quality of life. Poor oral health and xerostomia are often present and may have a negative effect on masticatory function and nutrition, precipitating avoidance of difficult-to-chew foods. There is no evidence that the provision of prosthetic therapies can markedly improve dietary intakes; however, it might improve oral comfort and quality of life and avoid enteral alimentation.

Lower gastrointestinal bleeding due to cytomegalovirus ileal ulcers in an immunocompetent man

Cytomegalovirus (CMV) infections are commonly reported in severely immunocompromised hosts and ulcers of the alimentary tract are frequently observed in systemic CMV infections. However, invasive and ulcerative disease of the gastrointestinal (GI) tract caused by CMV has also been reported in healthy adults. Many reports show that a CMV infection can produce localized ulcerations in the esophagus, stomach, small intestine, and colon in nonimmunocompromised individuals. The most common site of involvement by CMV infection in the GI tract is the colon followed by the upper GI tract and the least common site is the small intestine. Although GI bleeding is one of the major presenting symptoms of patients with CMV infections of the GI tract, lower GI bleeding due to CMV ileal ulcers in immunocompetent patients, to our knowledge, has not been reported in the English literature. Recently, we experienced a case of lower GI bleeding due to CMV ileal ulcers in a 57-year-old man who had no evidence of immunocompromise. This case suggests that small intestinal ulcers due to CMV infection should be included in the differential diagnosis of lower GI bleeding even in immunocompetent hosts.

Oxidative stress effect on the activation of hepatic stellate cells

Collagen is the most excessive extracellular matrix protein in hepatic fibrosis. Activated, but not quiescent, hepatic stellate cells (HSCs) have a high level of collagen and a smooth muscle actin (alpha SMA) expression. HSCs play a key role in the pathogenesis of hepatic fibrosis. We analyzed a mechanism leading to HSC activation by evaluating the role of oxidative stress and the expression of NFkB. In vitro study HSCs were proliferated (PCNA:2% vs 68%) and activated (alpha SMA: 5% vs 78%) by ascorbate/FeSO4, and HSCs activated by type I collagen were blocked (PCNA: 97% vs 4%, a SMA: 86% vs 9%) by a-tocopherol. In vivo study means of a SMA positive cells in liver at 400 x HPF were 48.3+/-5.2 and 15.2+/-1.8 and [3H]thymidine uptake of HSC was 529.2+/-284.8 cpm and 223.0+/-86.3 cpm in control and a-tocopherol treated group respectively at 32 hours after CCl4 injection. Nuclear extracts from activated, but not from quiescent, HSCs formed a complex with the NFkB cognate oligonucleotidesand alpha-tocopherol inhibited this bindings. This study indicates that oxidative stress plays an essential role through the induction of NFkB on HSC activation.

A case of minute intraductal papillary mucinous tumor of the pancreas presenting with recurrent acute pancreatitis

Intraductal papillary mucinous tumor (IPMT) of the pancreas, a lesion consisting of mucin-producing cells with neoplastic potential, is characterized by duct ectasia, mucin hypersecretion, often extensive papillary intraductal growth, varying degrees of cytologic atypia, and relatively indolent growth. The clinical presentation of IPMT of the pancreas is characterized by chronic or recurrent attacks of abdominal discomfort often in association with low level pancreatic enzyme elevations. Less commonly these lesions may be detected as asymptomatic radiographic abnormalities. Interestingly, a case of a minute IPMT (2 mm in height and 7 mm in length, adenoma) in the main pancreatic duct presenting with acute pancreatitis in a 55 year-old man has been reported in the Japanese literature. Recently, we also experienced a case of a minute IPMT in a branch pancreatic duct causing repeated bouts of acute pancreatitis in a 75 year-old man. A filling defect at the neck of the main pancreatic duct seen on an endoscopic retrograde pancreatogram performed after recovery of the second attack of acute pancreatitis led the patient to undergo an exploratory laparotomy. After a near-total pancreatectomy was carried out, a minute (3 x 7 mm) IPMT of borderline malignancy was discovered in a branch duct at the head portion near the pancreatic neck without any lesions in the main pancreatic duct. Surprisingly, despite the resective surgery the patient died of carcinomatosis 8.5 months after the operation. We herein report a case of a minute but aggressive IPMT of the pancreas with a review of the literature.

Tissue plasminogen activator and plasminogen activator inhibitor-1 in human choledochal bile

Fibrinolytic properties have been detected in animal and human gallbladder (GB) bile. Plasminogen activator inhibitor-1 (PAI-1) has been reported in greater concentration in GB stone bile and may be a nucleating factor in the pathogenesis of GB stone formation. It is unknown whether or not human choledochal bile has similar properties, which could have a role in choledocholithiasis. The aims of this study were to determine the presence of fibrinolytic properties of human choledochal bile and to compare those properties among normal, acalculous, and calculous-infected choledochal bile. Tissue plasminogen activator (t-PA) and PAI-1 of choledochal bile were measured by enzyme linked immunosorbent assay in patients with cholangitis due to acalculous bile duct obstructions (n = 9), choledocholithiasis with cholangitis (n = 20), and normal bile (n = 7). The t-PA concentration of choledochal bile was no different among the three groups (acalculous-infected bile, median 4.61 ng/ml, and calculous-infected bile, 4.61 ng/ml, versus normal bile, 7.33 ng/ml). PAI-1 was detected in choledochal bile in significantly greater concentrations in patients with acalculous cholangitis due to bile duct obstructions and choledocholithiasis with cholangitis (acalculous-infected bile, median 0.36 ng/ml, and calculous-infected bile, 0.1 ng/ml, versus normal bile, 0.02 ng/ml, p < 0.05), but the bile concentration of PAI-1 was no different between the acalculous and calculous-infected choledochal bile. Human choledochal bile possesses t-PA and PAI-1. PAI-1 was present in greater concentrations in both acalculous and calculous-infected choledochal bile. Increased levels of PAI-1 may be an epiphenomenon of cholangitis rather than a factor in the pathogenesis of choledocholithiasis.

Dental care of elderly in nursing homes: perceptions of managers, nurses, and physicians

Epidemiologic studies have shown that the oral health of residents in nursing homes is poor. This can be due to their impaired ability to maintain appropriate oral hygiene or to a lack of interest in oral care among those responsible for the care. The purpose of this study was to assess the attitudes of managers, caregivers, and physicians with regard to oral health care issues of their residents. A questionnaire sent to the managers of the 65 nursing homes in Geneva was returned by 47 (69%). According to the managers, 85% of the nursing homes organized transportation for the residents to a dental office; dental care with follow-up treatment was organized in 79% of the facilities; 68% of the facilities organized treatment for dental emergencies. Another questionnaire was distributed to 169 caregivers in 13 nursing homes. A majority had received no education in oral hygiene care of the residents. The caregivers did accept responsibility for oral hygiene care, but preferred to share it with a dentist responsible for the oral health care of the residents. Only 33% of the physicians indicated that they carried out a systematic examination of the oral cavity, and 20% agreed that the oral cavity might be an integrated part of the body. The majority of the physicians were in favor of more information on oral diseases and regular visits by a dentist; however, close collaboration with a dentist on oral health issues had a low priority.

Endoscopic retrograde pancreatographic findings of pancreatic lipomatosis

Pancreatic lipomatosis is characterized by fatty infiltration or replacement of the pancreas, and has been associated with many conditions. We recently experienced two cases of pancreatic lipomatosis in patients with pancreatic pseudocyst and a case of lipomatosis in diabetes mellitus. In these patients, abrupt obstruction of the main pancreatic duct with smooth tapering is a typical endoscopic retrograde pancreatography (ERP) finding of pancreatic lipomatosis and must be differentiated with pancreatic carcinoma.

Non-alcoholic duct-destructive chronic pancreatitis: recognition before definitive treatment

Non-alcoholic duct-destructive chronic pancreatitis is a new entity that differs morphologically and pathogenetically from alcoholic chronic pancreatitis. Some clinical and imaging features of this entity resemble those of pancreatic cancer, and hence most of the reported cases underwent pancreatic resections including an invasive pancreaticoduodenectomy. Recognition of this new entity before a definitive treatment is therefore important to avoid an unnecessary pancreatic resection. Recently, we experienced a case of non-alcoholic duct-destructive chronic pancreatitis in an 80-year-old man presenting with obstructive jaundice and whose radiologic features were characteristic as originally described. Recognition of this new entity before definitive treatment enabled us to manage this patient optimally. In addition, the relation between non-alcoholic duct-destructive chronic pancreatitis and chronic pancreatitis with diffuse irregular narrowing of the main pancreatic duct is discussed.

A novel primer-extension assay for the detection of a G to A mutation in the distal precore region of hepatitis B virus DNA

The roles of genetic heterogeneity of the hepatitis B virus (HBV) precore gene in the pathogenesis of HBV infection are unclear. Various methods have been used to detect nucleotide (nt) 1896 precore mutants. We established a new primer-extension assay to facilitate the detection of these mutants. This assay is based upon the fact that there is no adenine in the distal precore region of wild-type HBV. Polymerase chain reaction (PCR)-amplified template DNA was denatured and annealed to the [gamma-32P]-labelled primer. During primer extension in the presence of DNA polymerase and dCTP, dGTP, dTTP and ddATP, the reaction terminates if there is a nucleotide A. When mixtures of different ratios of wild-type and nt 1896 precore mutants were analysed in the primer-extension assay, correlation between the percentage known amounts and the percentage measured amounts of nt 1896 precore mutants was excellent (r2=0. 9669). When the primer-extension assay and direct sequencing were compared in hepatitis B e antigen (HBeAg)-positive and -negative chronic active hepatitis B patients, the primer-extension assay detected a greater number of nt 1896 precore mutants than direct sequencing and thus most HBV infections were found to be mixed infections. In conclusion, the primer-extension assay is a reliable and sensitive method for the detection of nt 1896 precore mutants.

Cytoplasmic expression of hepatitis B core antigen in chronic hepatitis B virus infection: role of precore stop mutants

AIMS/BACKGROUND

The cytoplasmic expression of HBcAg is a possible target of immune hepatocytolysis and it is important for the pathogenesis of hepatic injury in chronic hepatitis B virus (HBV) infection. Cytoplasmic HBcAg expression has been suggested to be related to the precore sequence of HBV, HBV DNA level or cell cycle of hepatocytes and the aim of this study was to understand its mechanism.

MATERIAL/METHODS

We studied the expression pattern of HBcAg and its relationship to serum HBV DNA levels, cell proliferation activity of hepatocytes and precore mutation using 66 patients' sera and biopsied liver specimens of chronic hepatitis B.

RESULTS

The expression patterns of HBcAg were cytoplasmic predominant (CP) in 17 cases, nuclear and cytoplasmic (NC) in 10 cases and nuclear predominant (NP) in 9 cases and negative in 30 cases. CP expression cases showed a higher grade of hepatitis activity than NP expression cases. Serum HBV DNA levels showed a wide range and there was no significant difference according to the expression pattern of HBcAg. Cell proliferation activity of hepatocytes, measured by Ki-67 (MIB-1) labelling index was higher in CP expression cases than in NP expression cases and it was also significantly higher in cases of high grade than in low grade hepatitis activity. The precore region was evaluated by primer extension assay in 51 cases and there were 16 cases of 1896 precore mutant, 23 cases of wild type, 12 cases of mixed infection of 1896 precore mutant type and wild type. CP expression of HBcAg was significantly more frequent in 1896 precore mutant cases (86%) than in wild type cases (26%).

CONCLUSION

CP expression of HBcAg is the major pattern of 1896 precore mutant cases and it might be involved in the severe liver injury of precore mutants. One of the mechanisms regulating CP HBcAg expression is suggested to be precore mutation of HBV as well as cell cycle of hepatocyte.

Obstructive jaundice and acute cholangitis due to papillary stenosis

Papillary stenosis is characterized by fixed fibrosis leading to structural outflow obstruction and it is usually secondary to inflammation and fibrosis from the chronic passage of gallstones, episodes of acute pancreatitis, chronic pancreatitis, sclerosing cholangitis, peptic ulcer disease, and cholesterolosis. However, obstructive jaundice with or without acute cholangitis which leads the physician to suspect the presence of malignancy as a cause is a rare manifestation of papillary stenosis. We report here a case of papillary stenosis presenting with obstructive jaundice and acute cholangitis. The lesion was so difficult to exclude the presence of malignancy preoperatively and intraoperatively that a pylorus-preserving pancreaticoduodenectomy was performed. Histologic examination of the resected specimen revealed fibrosis, adenomatoid ductal hyperplasia, and mild chronic inflammation of the papilla of Vater and distal common bile duct.

Villous adenoma of the bile ducts: a case report and a review of the reported cases in Korea

Villous adenomas are benign epithelial lesions with malignant potential which can occur at any site in the gastrointestinal tract. They are usually encountered in the rectum and colon, less frequently in the small bowel and very rarely in the biliary trees. Nine cases of bile duct villous adenomas have been reported in the literature. However, 4 cases of bile duct villous adenomas have been reported in the Korean literature. Recently, we experienced a case of villous adenoma in the common hepatic duct in a 77-year-old man presenting with obstructive jaundice in which preoperative histologic diagnosis of villous adenoma played a critical role in managing this patient. Herein, we present a case report of bile duct villous adenoma and a review of the reported cases in Korea to help define and manage this rare disease entity in the bile ducts. In addition, confusing nomenclature of bile duct adenomas is discussed.

Nitinol self-expanding stents: when severe twisting occurs, self-expansion may ensue after a waiting period

One of the major disadvantages of nitinol endocoil stents is said to be incomplete deployment leading to twisting and stent dysfunction. We report a patient with irresectable pancreatic head cancer where severe twisting of the nitinol stent occurred which resolved on the day after stent insertion; the stent took its normal shape ten days later, whereafter the patient lived without stent-related problems for one year until his death. This shows that prospective management rather than immediate stent extraction may be warranted in such cases of stent dysfunction.

Extrahepatic bile duct hepatocellular carcinoma without primary hepatic parenchymal lesions--a case report

Obstructive jaundice is rarely a presenting symptom of hepatocellular carcinoma (HCC). Most of the cases in the literature describing obstructive jaundice by HCC have a major hepatic component. Extrahepatic HCCs without primary hepatic parenchymal lesions are extremely rare. We encountered a case of extrahepatic HCC without primary hepatic parenchymal lesions in a 36-year-old man who presented with jaundice. We extensively sought primary hepatic parenchymal lesions preparatively and postoperatively with hepatic angiography and combined computed tomography (CT) studies, such as CT arterioportography and lipiodol-CT. The patient has been followed up for 1 year without definite evidence of recurrence. We herein report an unusual manifestation of HCC.

Anorectal dysfunction in systemic sclerosis

This study was aimed to evaluate the anorectal dysfunction in systemic sclerosis (SSc) and propose the clinical significance of anorectal manometry in patients with SSc. Seven patients with SSc were evaluated with manometry for anorectal function and an additional 11 normal subjects were collected as a control group. The study group underwent esophageal manometry as well and the correlation between the degree of anorectal and esophageal dysfunction was evaluated. Patients showed a lower tolerance for balloon distention of the rectum than controls (minimal sensory volume and urgency volume, P < 0.05). The resting and squeezing pressure of the anal sphincter and the functional length of the anal canal showed no significant difference in these two groups. Rectoanal inhibitory reflex was absent in one (14%) and diminished in two (29%) of seven patients with SSc. SSc patients also showed abnormal esophageal manometry findings, notably decreased LES pressure and body amplitude of distal 2/3 esophagus. The comparison between manometric profiles of anorectum and esophagus showed no significant correlation by statistical analysis. In conclusion, our data could suggest that anorectal function may be impaired in patients with SSc which could reflect the involvement of the anorectum by the disease, and that anorectal manometric studies can be useful to detect such dysfunction in patients with SSc, even before clinical symptoms.

A case of flutamide-induced acute cholestatic hepatitis--a case report

Flutamide, an oral nonsteroidal, antiandrogenic, anilid compound which inhibits the uptake and binding of androgens to nuclear receptors in the prostate, is used with or without LH-RH analogues for treatment of patients with metastatic carcinoma of the prostate. Clinically significant hepatotoxicities such as toxic hepatitis, cholestatic hepatitis, hepatic failure, and even death have rarely been reported in the English literature, but no case has been reported in Korea. A 75-year-old man with metastatic carcinoma of the prostate had taken flutamide (750 mg/day) for 7 months and suddenly developed jaundice and general weakness. The findings of blood chemistries were compatible with cholestatic hepatitis, but ultrasonography, viral marker and auto-antibody studies did not reveal any attributable causes. Histologic examination of a sono-guided liver biopsy only disclosed centrilobular cholestasis, nuclear glycogenosis and mild sinusoidal lymphocytic infiltration. Discontinuation of flutamide resulted in an almost full recovery of the patient's liver function in 2 months. We, herein, report a case of flutamide-induced acute choestatic hepatitis with a brief review of the literature.

Spontaneous bowel perforation during the course of acute pancreatitis--a case report

We recently experienced a case of spontaneous perforation of infected necrosis into the colon and duodenum during the course of acute pancreatitis in a 63 year-old male patient. Enteric perforations or fistulas in the setting of acute pancreatitis implicate severe underlying pathology and have substantial morbidity and mortality. In the meantime it has generally been accepted that infected pancreatic or peripancreatic necrosis should be managed surgically as soon as possible. Enteric perforations in the present case contributed to transient improvement of the patient's infection sign and condition, and thus an early operation was able to be avoided. Delayed surgical management resulted in complete recovery of the patient without postoperative morbidity. Herein we report an unusual complication of acute pancreatitis.

Examiner agreement on periodontal indices during dental surveys of elders

Indices used to evaluate periodontal health have been widely accepted in epidemiological studies, yet their reliability cannot be guaranteed. The aim of this study was to evaluate the reliability of periodontal indices applied on elders. 19 elderly subjects, 73-years-old on average, were examined at a 1st appointment by 2 independent examiners. They were re-examined 2 weeks later during a 2nd session. The examinations were performed in a dental chair with good illumination. Periodontal health was evaluated using the community periodontal index of treatment need, and tooth mobility was evaluated using 2 different indices. Inter and intra-examiner agreements were evaluated using kappa statistics. Taken as an overall measurement, the CPITN was a reliable assessment of periodontal treatment need in elders. Disagreement occurred mainly on the evaluation of bleeding and shallow pockets. The detection of fairly mobile teeth was reliable; however, the performance of the more sensitive scale was deceptive. it seems that, in the case of tooth mobility, a choice has to be made between sensitivity or reproducibility. It can be concluded that examiners should be trained carefully since the reliability of the CPITN and tooth mobility evaluation were good but close to a critical level for which an agreement is classified as poor.

Dysphagia due to mediastinal tuberculous lymphadenitis presenting as an esophageal submucosal tumor: a case report

Mediastinal tuberculous lymphadenitis is rare in adults, and it is even rarer for dysphagia to be the presenting symptom of mediastinal tuberculous lymphadenitis. Mediastinal tuberculous lymphadenitis with esophageal symptoms has been presented as esophageal ulceration, mucosal or submucosal mass with ulceration, fistula or sinus formation, extrinsic compression, or displacement of the esophagus. An exaggerated form of extrinsic compression may be presented as a submucosal tumor, radiologically or endoscopically. A barium esophagography of a 34 year-old woman with painful dysphagia revealed a large submucosal tumor-like mass on the mid-esophagus. The symptom was spontaneously improved over a 3-week period together with reduction of the mass size. A computed tomography of the chest disclosed an enlarged subcarinal lymph node and histologic examination of the specimen obtained by thoracoscopic biopsy brought about a diagnosis of tuberculosis. We herein report a case of mediastinal tuberculosis with unusual manifestations.

Examiner agreement on caries detection and plaque accumulation during dental surveys of elders

Indices used to evaluate plaque accumulation and coronal caries have been widely accepted in epidemiological studies, yet their reliability cannot be guaranteed. The aim of this study was to evaluate the reliability of clinical criteria used in coronal and root caries diagnosis and oral hygiene evaluation as applied in elders. Nineteen elderly subjects, 73 years old on average, were examined at a first appointment by two independent examiners. They were re-examined two weeks later. Plaque accumulation was evaluated using the Plaque Index (PI) and coronal and root caries were detected according to the WHO criteria and Fejerskov et al. (1991), respectively. Recurrent caries was recorded as recommended by WHO and by probing at the interface tooth-restoration. Inter- and intra-examiner agreement was evaluated using kappa statistics. The PI score showed good reliability except for examiner b, for whom a simplification of the 4-point scale in 3-point scale improved significantly the reliability. The prevalence of coronal caries was very low and intra- and inter-examiner agreement was poor. Most of the root caries lesions were covered by plaque and the kappa values indicated only poor agreement. Recurrent caries were found with good agreement using WHO criteria but the detection with the probe was not reliable. In conclusion, it seems that examiners should be trained carefully to maximise their reliability and that plaque should be removed to obtain reliable diagnoses of caries. Retraining and calibration may be necessary for surveys continuing over a long period.

A case of abdominal cocoon

Abdominal cocoon is a rare disease of the peritoneum and almost invariably presents as an acute or subacute intestinal obstruction with or without a mass. The etiology of this disease is largely unknown and abdominal cocoon of unknown etiology has been limited to the tropical and subtropical zones and primarily affects young adolescent females. In the temperate zone, only one case has been reported from the United Kingdom, but the patient was also born in Pakistan. No case of abdominal cocoon purely developed in the temperate zone has been reported. Recently, we experienced a case of abdominal cocoon in a 34-year-old female patient(Korean) who had never been abroad. The diagnosis was made postoperatively by reviewing the literature. We herein report this rare condition developed in an unusual geographical location with a brief review of the literature.

A large common bile duct stone migrated from the gallbladder through a cholecystohepaticodochal fistula: an unusual complication of Mirizzi syndrome type II

Mirizzi syndrome with a biliobiliary fistula (Mirizzi syndrome type II) is a rare complication of a long-standing gallbladder stone disease. It is even rarer for a gallbladder stone to migrate through a biliobiliary fistula into the common duct. We encountered this interesting complication of Mirizzi syndrome type II in an 86 year-old female patient. A large gallbladder stone migrated into, and impacted into the distal common bile duct through a cholecystohepaticodochal fistula. The stone was resistant to mechanical lithotripsy and was treated with biliary endoprosthesis and oral bile acids.

Comparison of immunomodulative effects of histamine-2 receptor antagonists in gastric cancer patients: focus on the lymphoblastogenesis and cytotoxicity of peripheral blood mononuclear cells

A proposed mechanism of the immunomodulative effects of histamine-2 receptor antagonist (H2-RA) has been considered to be the inhibition of suppressor T-lymphocyte activity, an increase in interleukin-2 production of helper T-lymphocytes, and an enhancement of natural killer cell activity. Since there is a lack of comparative data about the immunomodulative effects of various H2-RAs, cimetidine, ranitidine and famotidine on peripheral blood mononuclear cells (PBMC), study of the comparison of the actions of H2-RA will be required. We compared the immunomodulative effect of each H2-RA on PBMC in patients with gastric cancer. DNA synthesis, cytotoxicity of PBMC against K562 cells and gastric cancer cell lines, and the levels of supernatant soluble interleukin-2 receptor (sIL-2R) were measured after the addition of each H2-RA, respectively. Increased suppressor cell activities were attenuated and restored to the levels of normal controls by the addition of cimetidine to H2-RA. Statistically significant lymphoblastogenesis and cytotoxicity against K562 cells were observed only in cimetidine-treated PBMC (P < 0.05). Such effects were not observed in ranitidine- or famotidine-treated PBMC. Neither cimetidine- nor ranitidine-activated activated PBMC showed any significant cytotoxicity against gastric cancer cells. Significantly increased levels of sIL-2R were found in supernatants obtained from culture flasks treated with cimetidine or ranitidine and phytohemagglutinin (P < 0.01). A significant correlation was found between the cytotoxicity of cimetidine- or ranitidine-treated PBMC and supernatant sIL-2R (P < 0.05). In conclusion, the most strongly modulative substance among H2-RAs was cimetidine and the least modulative drug was famotidine.(ABSTRACT TRUNCATED AT 250 WORDS)

Duodenal ectopic pancreas complicated by chronic pancreatitis and pseudocyst formation--a case report

Ectopic pancreas is no longer a rare clinical condition, but its unusual clinical manifestations, locations or complications are of clinical interest. We experienced a case (a 48 year-old male patient) of duodenal ectopic pancreas complicated by chronic pancreatitis and pseudocyst formation of which preoperative imaging findings mimicked a large duodenal submucosal tumor with cystic degeneration such as a leiomyosarcoma. Simultaneous chronic pancreatitis was also demonstrated in the isotopic pancreas of the patient postoperatively. Herein we report a rare clinical condition occurring in an ectopic pancreas with a brief review of the literature.

Obstructive jaundice due to compression of the common hepatic duct by right hepatic artery--a case associated with the absence of the lateral segment of the left hepatic lobe

Various benign and malignant conditions can cause biliary obstruction. We present a rare case of obstructive jaundice due to the compression of the common hepatic duct by the anteriorly overriding right hepatic artery. This case was also associated with the absence of the lateral segment of the left hepatic lobe. The patient was a 39 year-old housewife with a 4-day history of jaundice and occasional febrile sensation. An abdominal computed tomography showed absence of the lateral segment of the left hepatic lobe and a percutaneous transhepatic cholangiography showed a band-like filling defect of 2 mm width at the level of the upper common hepatic duct. The anteriorly overriding right hepatic artery compressing the common hepatic duct and the absence of the lateral segment of the left hepatic lobe were confirmed by operation.

Mutations in the pre-core region of hepatitis B virus DNA in patients with chronic liver diseases

To investigate the prevalence of point mutation in the pre-core (pre-C) region of hepatitis B virus (HBV) DNA, we performed dot blot hybridization and sequencing of enzymatically amplified HBV DNA from the sera of 25 patients with HBeAg-positive and 32 patients with HBeAg-negative chronic liver diseases. The pre-C region of HBV DNA was successfully amplified by polymerase chain reaction (PCR) from 55 (96.5%) of 57 sera. According to the status of serum HBeAg, HBV DNA was amplified from all 25 sera of HBeAg-positive patients and 30 (93.8%) of 32 sera of HBeAg-negative patients. All amplified DNA from the sera of 25 patients with HBeAg-positive and that from 28 (93.3%) of 30 patients with HBeAg-negative chronic liver diseases hybridized with the wild type probe. In addition, that from 5 (20.0%) among 25 patients with HBeAg-positive and 16 (53.3%) among 30 patients with HBeAg-negative chronic liver diseases hybridized also with the mutant type probe. These results suggest that the prevalence of point mutation in the pre-C region of HBV DNA is relatively high in patients with HBeAg-negative chronic liver diseases and further study is mandatory to identify the significance of this mutation.

The effects of adrenalectomy on the cardiovascular responses to delta 1-tetrahydrocannabinol in rats

1. In urethane anaesthetized sham-operated rats, intravenous administration of delta 1-THC (1 mg/kg) caused an immediated and prolonged fall in blood pressure, with a concomitant reduction in pulse rate. 2. In rats which had been adrenalectomized 24 h previously, delta 1-THC (1 mg/kg, i.v.) also caused a depressor response, but it was significantly shorter in duration than that observed in sham-operated animals. The durations of the cardiac slowing effect were similar in both groups of rats. 3. Hydrocortisone pretreatment (25 microgram/kg, i.v.), given 45 min before delta 1-THC, restored the duration of the depressor response to delta 1-THC in adrenalectomized rats, but it did not have any effect on the bradycardia induced by delta 1-THC. 4. Hydrocortisone did not produce any significant effect on the hypotensive action of delta 1-THC in sham-operated rats, but the cardiac slowing effect was markedly potentiated. 5. These results suggest a lack of correlation between the hypotensive and cardiac slowing actions of the drug and that a certain level of adrenal steroids is necessary for the maintenance of the depressor response to delta 1-THC.