Factors associated with prolonged viral detection in asymptomatic and mildly symptomatic patients with SARS-CoV-2 infection

INTRODUCTION

Data on the clinical course and duration of viral RNA detection in patients with mild or asymptomatic coronavirus disease 2019 are limited.

METHODOLOGY

In this retrospective analysis, clinical characteristics and serial real-time reverse transcriptase-polymerase chain reaction (RT-PCR) results were reviewed in a cohort of 1186 asymptomatic and mildly symptomatic coronavirus disease 2019 patients in South Korea. Factors associated with prolonged duration of RT-PCR positivity for severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) were also evaluated. Patients with two consecutive negative RT-PCR tests ≥ 24 hours apart were considered to be in virologic remission and discharged.

RESULTS

The average virologic remission period, defined as the number of days from diagnosis to virologic remission, was 22.0 ± 9.7 days; patients with longer than 30 days accounted for 21.2% (251/1186) of the population. Patients who took longer than 30 days to achieve virologic remission had a higher frequency of overall symptoms (p < 0.001) and respiratory symptoms (p < 0.001). In multivariate analysis using Cox-proportional hazard regression, it was confirmed that respiratory symptoms (hazard ratio [HR], 0.7372; 95% confidence interval [CI], 0.6540-0.8311) and gastrointestinal symptoms (HR, 0.8213; 95% CI, 0.6970-0.9679) were independent factors associated with prolonged virologic remission. Age and co-morbidity such as diabetes and hypertension were not associated with the prolonged RT-PCR positivity.

CONCLUSIONS

A considerable percentage of asymptomatic and mildly symptomatic patients with coronavirus disease 2019 showed prolonged RT-PCR positivity for SARS-CoV-2; which was independently associated with the presence of symptoms, but not with age and co-morbidity.

Double tract reconstruction versus double flap technique: short-term clinical outcomes after laparoscopic proximal gastrectomy for early gastric cancer

BACKGROUND

Laparoscopic proximal gastrectomy (LPG) is increasingly preferred for operative management of early gastric cancer, although there is no consensus on a standard reconstruction method after resection. Two popular methods used after LPG are double tract reconstruction (DTR) and double flap technique (DFT). This study assessed comprehensive clinical outcomes including quality of life (QoL) and body composition change 1 year after DFT and DTR.

METHODS

We retrospectively reviewed prospectively collected data from 51 to 18 patients who underwent DTR and DFT, respectively, between September 2014 and December 2018. Short-term surgical outcomes, presence of reflux esophagitis, nutritional supplementation, medications, nutritional status (laboratory results and body composition analysis), and QoL measured preoperatively and at 1 year postoperatively were compared between both groups.

RESULTS

Both groups did not differ significantly in clinicopathological characteristics. The DFT as compared to the DTR group required significantly longer time for anastomosis (79.4 vs. 60.9 min, p < 0.001) and use of fewer staplers (3.39 vs. 6.86, p < 0.001). While the presence of endoscopic reflux esophagitis and iron/vitamin B₁₂ replacement were comparable, the DTR group showed a higher tendency of taking anti-reflux medications for reflux symptoms (DTR: 13.7% vs. DFT: 0.0%, p = 0.177). The DTR group lost significantly more weight (p = 0.038) and body fat (p = 0.009). QoL analysis showed significant deterioration in diarrhea, eating restriction, and taste problems in both groups (DTR group: p = 0.008, p < 0.001, p = 0.010, respectively, and DFT group: p = 0.017, p = 0.024, p = 0.034, respectively). However, only the DTR group showed significant deterioration in physical function (p = 0.009), role function (p = 0.033), nausea/vomiting (p = 0.041), appetite loss (p = 0.019), dysphagia (p = 0.001), pain (p = 0.025), and body image (p = 0.004).

CONCLUSIONS

Despite requiring a longer anastomosis time, performing DFT after LPG was shown to be an ideal reconstruction method in terms of better 1-year QoL and nutritional outcome. Further larger studies over longer postoperative periods are necessary to confirm our findings.

Prolonged SARS-CoV-2 detection and reversed RT-PCR results in mild or asymptomatic patients

BACKGROUND

The clinical course and viral detection period in mild or asymptomatic coronavirus disease 2019 (COVID-19) patients are not yet known. The presumed low diagnostic sensitivity of upper respiratory specimens for Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) makes it difficult to confirm infection and recommend de-isolation.

METHODS

We retrospectively reviewed real-time reverse transcriptase-polymerase chain reaction (RT-PCR) test results of mild or asymptomatic COVID-19 patients who were admitted at the Daegu-Gyeongbuk 7th community treatment centre in Korea between 9 March 2020 and 10 April 2020. Patients underwent an upper respiratory RT-PCR test every week until discharge. From the RT-PCR results, we evaluated the rate of prolonged (>3 weeks) SARS-CoV-2 RNA positivity. We analysed the proportion of reversed results, defined as a positive or indeterminate result one day after a negative RT-PCR result, according to time (<14, 15-21, 22-28, >28 days) from the initial positive RT-PCR result.

RESULTS

In 23% (69/300) of patients, SARS-CoV-2 was detected more than 3 weeks after the initial positive RT-PCR. In 14% (42/300) of patients, the RT-PCR results were positive for more than 4 weeks. For 37.5% (152/405) of negative RT-PCR results, the results were reversed in the next day's test. And 43.5% (123/283) of negative RT-PCR results were reversed within 3 weeks of diagnosis.

CONCLUSIONS

The detection of SARS-CoV-2 lasting more than 3 weeks was common in mild or asymptomatic patients. Upper respiratory RT-PCR results were frequently reversed from negative to positive.

Role of tumour location and surgical extent on prognosis in T2 gallbladder cancer: an international multicentre study

BACKGROUND

In gallbladder cancer, stage T2 is subdivided by tumour location into lesions on the peritoneal side (T2a) or hepatic side (T2b). For tumours on the peritoneal side (T2a), it has been suggested that liver resection may be omitted without compromising the prognosis. However, data to validate this argument are lacking. This study aimed to investigate the prognostic value of tumour location in T2 gallbladder cancer, and to clarify the adequate extent of surgical resection.

METHODS

Clinical data from patients who underwent surgery for gallbladder cancer were collected from 14 hospitals in Korea, Japan, Chile and the USA. Survival and risk factor analyses were conducted.

RESULTS

Data from 937 patients were available for evaluation. The overall 5-year disease-free survival rate was 70·6 per cent, 74·5 per cent for those with T2a and 65·5 per cent among those with T2b tumours (P = 0·028). Regarding liver resection, extended cholecystectomy was associated with a better 5-year disease-free survival rate than simple cholecystectomy (73·0 versus 61·5 per cent; P = 0·012). The 5-year disease-free survival rate was marginally better for extended than simple cholecystectomy in both T2a (76·5 versus 66·1 per cent; P = 0·094) and T2b (68·2 versus 56·2 per cent; P = 0·084) disease. Five-year disease-free survival rates were similar for extended cholecystectomies including liver wedge resection versus segment IVb/V segmentectomy (74·1 versus 71·5 per cent; P = 0·720). In multivariable analysis, independent risk factors for recurrence were presence of symptoms (hazard ratio (HR) 1·52; P = 0·002), R1 resection (HR 1·96; P = 0·004) and N1/N2 status (N1: HR 3·40, P < 0·001; N2: HR 9·56, P < 0·001). Among recurrences, 70·8 per cent were metastatic.

CONCLUSION

Tumour location was not an independent prognostic factor in T2 gallbladder cancer. Extended cholecystectomy was marginally superior to simple cholecystectomy. A radical operation should include liver resection and adequate node dissection.

Optimal surgical treatment in patients with T1b gallbladder cancer: An international multicenter study

BACKGROUND

There is no consensus on the optimal treatment of T1b gallbladder cancer (GBC) due to the lack of evidence and the difficulty of anatomy and pathological standardization.

METHODS

A total of 272 patients with T1b GBC who underwent surgical resection at 14 centers with specialized hepatobiliary-pancreatic surgeons and pathologists in Korea, Japan, Chile, and the United States were studied. Clinical outcomes including disease-specific survival (DSS) rates according to the types of surgery were analyzed.

RESULTS

After excluding patients, the 237 qualifying patients consisted of 90 men and 147 women. Simple cholecystectomy (SC) was performed in 116 patients (48.9%) and extended cholecystectomy (EC) in 121 patients (51.1%). The overall 5-year DSS was 94.6%, and it was similar between SC and EC patients (93.7% vs. 95.5%, P = 0.496). The 5-year DSS was similar between SC and EC patients in America (82.3% vs. 100.0%, P = 0.249) as well as in Asia (98.6% vs. 95.2%, P = 0.690). The 5-year DSS also did not differ according to lymph node metastasis (P = 0.688) or tumor location (P = 0.474).

CONCLUSIONS

SC showed similar clinical outcomes (including recurrence) and survival outcomes as EC; therefore, EC is not needed for the treatment of T1b GBC.

Hepatic ischemia/reperfusion injury disrupts the homeostasis of kidney primary cilia via oxidative stress

Acute kidney injury (AKI) is a major complication of hepatic surgeries. The primary cilium protrudes to the lumen of kidney tubules and plays an important role in renal functions. Disruption of primary cilia homeostasis is highly associated with human diseases including AKI. Here, we investigated whether transient hepatic ischemia induces length change and deciliation of kidney primary cilia, and if so, whether reactive oxygen species (ROS)/oxidative stress regulates those. HIR induced damages to the liver and kidney with increases in ROS/oxidative stress. HIR shortened the cilia of kidney epithelial cells and caused them to shed into the urine. This shortening and shedding of cilia was prevented by Mn(III) tetrakis(1-methyl-4-pyridyl) porphyrin (MnTMPyP, an antioxidant). The urine of patient undergone liver resection contained ciliary proteins. These findings indicate that HIR induces shortening and deciliation of kidney primary cilia into the urine via ROS/oxidative stress, suggesting that primary cilia is associated with HIR-induced AKI and that the presence of ciliary proteins in the urine could be a potential indication of kidney injury.

ERK1 Directly Interacts With JNK1 Leading to Regulation of JNK1/c-Jun Activity and Cell Transformation

ERK1 and ERK2 share a great deal of homology and have been presumed to have similar functions. Available antibodies recognize both isoforms making the elucidation of functional differences challenging. Mitogen-activated protein (MAP) kinase networks are commonly depicted in the literature as linear and sequential phosphorylation cascades; however, the activation of these pathways is not mutually exclusive. Little doubt exists that MAP kinases engage in crosstalk, but the extent or the direct effect of these "conversations" is unclear. Here, we report the possible points of direct interaction as "crosstalk" points between ERK1 and JNK1 and a potential mechanism for ERK1 function in repressing Ras/JNK-mediated cell transformation. ERK1, but not ERK2, directly interacts with and antagonizes JNK1 phosphorylation and activity, resulting in suppression of neoplastic cell transformation mediated by the Ras/JNK/c-Jun signaling pathway. Interestingly, ERK1 phosphorylation was increased in normal tissues compared to liver cancer tissues. Furthermore, predominant JNK/c-Jun activation was observed in liver cancer tissues. These phenomena can provide evidence for the existence of a functional association between ERK and JNK signaling pathways during in vivo tumorigenesis. Overall, our findings provide new evidence supporting the paradigm of an ERK1/JNK1 antagonistic interaction as a novel mechanism of trans-regulation between different MAP kinase signaling modules. J. Cell. Biochem. 118: 2357-2370, 2017. © 2017 Wiley Periodicals, Inc.

Outcomes and recurrence pattern after non-anatomic liver resection for solitary hepatocellular carcinomas

Backgrounds/Aims

Anatomic resection (AR) is preferred for eradicating portal tributaries in patients with hepatocellular carcinoma (HCC). However, the extent of resection is influenced by underlying liver disease and tumor location. We compared the surgical outcomes and recurrence pattern between non-anatomic resection (NR) and AR.

Methods

From March 2009 to February 2012, 184 patients underwent surgical resection for HCC. Among these, 79 patients who were primarily treated for a single tumor without rupture or macroscopic vascular invasion were enrolled. The patients were divided into 2 groups based on the extent of resection: AR (n=31) or NR (n=48). We compared the clinical characteristics, overall survival, disease-free survival, pattern of recurrence, and biochemical liver functions during the perioperative period between the two groups.

Results

The extent of resection had no significant effect on overall or disease-free survival rates. The overall 1- and 3-year survival rates were 97% and 82% in the AR group, and 96% and 89% in the NR group, respectively (p=0.49). In addition, the respective 1- and 3-year disease-free survival rates for the AR and NR groups were 84% and 63%, and 85% and 65%, respectively (p=0.94). On the other hand, the presence of hepatic cirrhosis and a tumor size of >5 cm were significant risk factors for recurrence according to multivariate analysis (p<0.001 and p=0.003, respectively). The frequency of early recurrence, the first site of recurrence, and the pattern of intrahepatic recurrence were similar between the 2 groups (p=0.419, p=0.210, and p=0.734, respectively); in addition, the frequency of marginal recurrence did not differ between the 2 groups (1 patient in the AR group and 2 in the NR group). The NR group showed better postoperative liver function than the AR group.

Conclusions

Non-anatomic liver resection can be a safe and efficient treatment for patients with a solitary HCC without rupture or gross vascular invasion.

CR6-interacting factor 1 is a key regulator in Aβ-induced mitochondrial disruption and pathogenesis of Alzheimer's disease

Mitochondrial dysfunction, often characterized by massive fission and other morphological abnormalities, is a well-known risk factor for Alzheimer's disease (AD). One causative mechanism underlying AD-associated mitochondrial dysfunction is thought to be amyloid-β (Aβ), yet the pathways between Aβ and mitochondrial dysfunction remain elusive. In this study, we report that CR6-interacting factor 1 (Crif1), a mitochondrial inner membrane protein, is a key player in Aβ-induced mitochondrial dysfunction. Specifically, we found that Crif1 levels were downregulated in the pathological regions of Tg6799 mice brains, wherein overexpressed Aβ undergoes self-aggregation. Downregulation of Crif1 was similarly observed in human AD brains as well as in SH-SY5Y cells treated with Aβ. In addition, knockdown of Crif1, using RNA interference, induced mitochondrial dysfunction with phenotypes similar to those observed in Aβ-treated cells. Conversely, Crif1 overexpression prevented Aβ-induced mitochondrial dysfunction and cell death. Finally, we show that Aβ-induced downregulation of Crif1 is mediated by enhanced reactive oxygen species (ROS) and ROS-dependent sumoylation of the transcription factor specificity protein 1 (Sp1). These results identify the ROS-Sp1-Crif1 pathway to be a new mechanism underlying Aβ-induced mitochondrial dysfunction and suggest that ROS-mediated downregulation of Crif1 is a crucial event in AD pathology. We propose that Crif1 may serve as a novel therapeutic target in the treatment of AD.

Prognostic factors in patients with middle and distal bile duct cancers

AIM: To identify the influence of the surgery type and prognostic factors in middle and distal bile duct cancers.

METHODS: Between August 1990 and June 2011, data regarding the clinicopathological factors of 194 patients with surgical and pathological confirmation were collected. A total of 133 patients underwent resections (R0, R1, R2; n = 102, 24, 7), whereas 61 patients underwent nonresectional surgery. Either pancreaticoduodenectomy (PD) or bile duct resection (BDR) was selected according to the sites of tumors and co-morbidities of the patients after confirming resection margin by the frozen histology in all cases. Univariate and multivariate analyses of clinicopathologic factors were performed, utilizing the Kaplan-Meyer method and Cox hazard regression analysis.

RESULTS: The overall 5-year survival rate for the 133 patients who underwent resection (R0, R1, and R2) was 41.2%, whereas no patients survived longer than 3 years among the 61 patient who underwent nonresectional surgeries. The 5-year survival rate of the patients who underwent a PD (n = 90) was higher than the rate of those who underwent BDR (n = 43), although the difference was not statistically significant (46.6% vs 30.0% P = 0.105). However, PD had a higher rate of R0 resection than BDR (90.0% vs 48.8%, P < 0.0001). If R0 resection was achieved, PD and BDR showed similar survival rates (49.4% vs 46.5% P = 0.762). The 5-year survival rates of R0 and R1 resections were not significantly different (49.0% vs 21.0% P = 0.132), but R2 resections had lower survival (0%, P = 0.0001). Although positive lymph node, presence of perineural invasion, presence of lymphovascular invasion (LVI), 7^th AJCC-UICC tumor node metastasis (TNM) stage, and involvement of resection margin were significant prognostic factors in univariate analysis, multivariate analysis identified only TNM stage and LVI as independent prognostic factors.

CONCLUSION: PD had a greater likelihood of curative resection and R1 resection might have some positive impact. The TNM stage and LVI were independent prognostic factors.

Classifying extrahepatic bile duct metachronous carcinoma by de novo neoplasia site

Extrahepatic bile duct (EHBD) cancer may occur metachronously, and these cancers are resectable with a favorable prognosis. We aimed to identify the pattern of metachronous EHBD cancer. We classified the cases of metachronous EHBD cancer reported in the literature thus far and investigated two new cases of metachronous EHBD cancer. A 70-year-old female underwent R0 bile duct resection for a type 1 Klatskin tumor (pT1N0M0). A 70-year-old male patient underwent R0 bile duct resection for a middle bile duct cancer (pT2N1M0). Imaging studies of both patients taken at 14 and 24 mo after first surgery respectively revealed a metachronous cholangiocarcinoma that required pancreaticoduodenectomy (PD). Histopathology of the both tumors after PD revealed cholangiocarcinoma invading the pancreas (pT3N0M0). Both patients have been free from recurrence for 6 years and 16 mo respectively after the second surgery. Through a review of the literature on these cases, we classified the pattern of metachronous EHBD cancer according to the site of de novo neoplasia. The proximal remnant bile duct was most commonly involved. Metachronous EHBD cancer should be distinguished from an unresectable recurrent tumor. Classifying metachronous EHBD cancer may be helpful in identifying rare metachronous tumors.

Predictive factors for invasive intraductal papillary mucinous neoplasm of the pancreas

BACKGROUNDS/AIMS

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas has malignant potential. Predicting invasive IPMN has proven difficult and controversial. We tried to identify predictive factors for invasive IPMN.

METHODS

Thirty six patients underwent resection for IPMN from February 2001 to July 2011. Clinicopathological features including demographic, imaging, microscopic, and serological findings were retrospectively reviewed. Receiver operating characteristic (ROC) curve analysis was used to analyze sensitivity and specificity of all possible cut-off values for the diameter of the main pancreatic duct and mass size predicting invasive IPMN. Student t-test, chi-square test, and logistic regression were used for univariate and multivariate analysis.

RESULTS

The mean age was 63.5±8.4 years. Males were more commonly affected (58.3% vs 41.7%). Pancreaticoduodenectomy was performed in 55.6% of patients, distal pancreatectomy in 36.1%, and central pancreatic resection in 8.3%. Non-invasive IPMNs were present in 80.6% (n=29), whereas invasive IPMNs were present in 19.4% (n=7). In univariate analysis, tumor location (p=0.036), Kuroda classification (p=0.048), mural nodule (p=0.016), and main duct dilatation (≥8 mm) (p=0.006) were statistically significant variables. ROC curve analysis showed that a value of 8 mm for the main duct dilatation and a value of 35 mm for the size of the mass lesion have 80% sensitivity and 75% specificity and 100% sensitivity and 82.6% specificity, respectively. However, in multivariate analysis, main ductal dilatation (≥8 mm) was identified to be the only independent factor for invasive IPMN (p=0.049).

CONCLUSIONS

Main duct dilatation appears to be a useful indicator for predicting invasive IPMN.

Radiosurgery for metastatic spinal tumors: follow-up MR findings

BACKGROUND AND PURPOSE

MR imaging is the primary tool for evaluation and monitoring of spinal tumors. We retrospectively analyzed the MR imaging findings before and after SRS for metastatic spinal tumors.

MATERIALS AND METHODS

We reviewed MR imaging findings on 79 metastatic spinal tumor lesions in 44 patients (29 male and 15 female)who had undergone radiosurgery between November 2003 and April 2008. Posttreatment MR imaging was evaluated retrospectively for 3 aspects: 1) changes in tumor volume; 2) changes in T2 signal intensity;and 3) changes in contrast enhancement patterns.

RESULTS

With regard to tumor volume on MR images, 32 lesions(40.5%) decreased in volume (group 1), 39 (49.4%) showed no change (group 2), and 8 (10.1%) increased in volume (group 3). T2 signal intensities were unchanged in 4 lesions (type 1), homogeneously increased in 3 (type 2), and changed to a homogeneously dark signal in 4 (type 4). The T2 signal intensity was increased and inter mixed with dark signal intensity (type 3) in 68 lesions. A decrease in contrast enhancement with or without non-enhancing foci was seen in 73 lesions. A persistent homogeneous enhancement pattern was seen in all 4 of the type 1 lesions, in 1 of the 3 type 2 lesions, and in 1 of the 68 type 3 lesions.

CONCLUSIONS

Main MR imaging features of locally controlled metastatic spinal tumors included no increase in tumor volume, increased T2 signal intensity with intermixed T2 dark signal intensity,and decreased contrast enhancement. Follow-up MR imaging also provided several patterns of tumor recurrence [corrected].

Prognostic factors after early recurrence in patients who underwent curative resection for hepatocellular carcinoma

BACKGROUND

The prognosis of the patients with early recurrence after curative hepatectomy for hepatocellular carcinoma (HCC) is usually dismal.

METHODS

One hundred twenty-four patients underwent curative resection for HCC at Kyungpook National University Hospital from January 2002 to December 2006. An early recurrence was defined as a recurrence within 2 years after a curative resection. The risk factors associated with an early recurrence were analyzed as well as other risk factors correlated with survival after early recurrence.

RESULTS

Early disease recurrence developed in 56 patients (45.2%). The risk factors associated with an early recurrence were a tumor size larger than 5 cm (P = 0.001) and the presence of tumor micrometastasis (P < 0.001). The 1 year/2 year overall survival, after early recurrence, was 57.0%/41.0% and the preoperative α-fetoprotein, C-reactive protein (CRP), tumor size, macroscopic vascular invasion, and number of tumors were associated with survival on the univariate analysis. The multivariate analysis showed that the independent risk factors for survival, after early disease recurrence, were a preoperative CRP >1.0 mg/dl and macroscopic vascular invasion. (P = 0.004, P < 0.001, respectively).

CONCLUSION

The preoperative CRP and macroscopic vascular invasion were associated with the aggressiveness of early recurrent HCC.

Living donor liver transplantation for acute hepatic failure caused by reactivation of hepatitis B virus infection after chemotherapy for hematologic malignancy: case reports

Cancer chemotherapy in chronic hepatitis B virus (HBV) carriers occasionally leads to acute hepatic failure (AHF) from viral reactivation resulting in an high mortality rate. In this situation, living donor liver transplantation (LDLT) can be life saving. Herein we have reported 2 cases of successful LDLT performed for AHF caused by reactivation of HBV infection during chemotherapy for hematologic malignancies. In case 1, a 38-year-old male HBV carrier with a neck mass was hisopathologically diagnosed as Hodgkin's lymphoma. During 4 cycles of chemotherapy he developed right upper quadrant pain and jaundice. Laboratory data (alanine amino transferase, 701 U/L, total bilirubin: 7.92 mg/dL, positive hepatitis B e antigen showed that he had experienced an acute exacerbation of chronic hepatitis. Soon, he developed grade IV hepatic encephalopathy with a total bilirubin level of 50.56 mg/dL and a model for End-Stage Liver Disease score of 40. After LDLT, he has been free of relapse for 52 months so far. In case 2, a 49-year-old male HBV carrier was diagnosed in the chronic phase of chronic myeloid leukemia. The patient had been under Imatinib treatment for 1 year until he was admitted for AHF. He developed grade II encephalopathy with a total bilirubin of 50.8 mg/dL. We performed LDLT; the patient has been free of relapse for 17 months. LDLT was a life-saving procedure for AHF caused by reactivation of HBV during chemotherapy for hematologic malignancy. It can provide long-term survival if the coexistent hematologic malignancy has been controlled.

First Report of Pyricularia grisea Causing Gray Leaf Spot on Lily in Korea

Lily is an economically important ornamental crop in Korea. In August 2008, severe leaf spot symptoms were observed on an oriental Lily 'Action' in a plant nursery in Daegu, Korea. Disease incidence was 20 to 30%. Initial symptoms were olive green-to-brown lesions on the leaf that developed into tan, elliptical, necrotic lesions. On severely infected leaves, lesions coalesced and killed the entire leaf blade. Infected leaves were surface disinfested with 70% ethanol for 30 s and 2% chlorox for 15 min before plating 1 cm² sections onto potato dextrose agar. Hyphae appeared 5 days after inoculation and pure culture. Conidia were hyaline, transversely septate with one to three septa; most had two. Conidia were obpyriform and measured 29 to 46 μm long and 7 to 17 μm wide. Mycelia morphology and conidia production were consistent with that described previously for Pyricularia grisea (1). Koch's postulates were fulfilled by spraying five, healthy, vegetative-stage plants with 2 × 10⁵ conidia per ml of sterile distilled water plus 0.05% Tween 20. As a control, five similar plants were sprayed with sterile water plus 0.05% Tween 20 only. Plants were placed inside plastic bags to maintain high relative humidity and incubated in a growth chamber at 25°C under fluorescent light for 14 h and at 20°C in darkness for 10 h. After 3 days, the plastic bags were removed and plants were maintained under the same conditions. Initial symptoms were observed 7 days after inoculation. Ten days after inoculation, disease symptoms on inoculated plants were similar to those previously described in the nursery. Control plants did not show any symptoms. Fungi isolated from these lesions had the same morphological characteristics as the ones isolated previously from plants in the nursery. To our knowledge, this is the first report of gray leaf spot on lily caused by P. grisea in Korea. References: (1) M. B. Ellis. Dematiaceous Hyphomycetes. CMI, Kew, Surrey, UK, 1971.

Annihilation of photochemical reactivity of photo-alignment layer

The gas-polymer and liquid-polymer interfacial reactions of photosensitive polyimide can annihilate photo-reactive carbon-carbon double bonds, which remain after photo-alignment process. The annihilation processes dramatically affect voltage holding ratio and reorientation of photo-active functional groups. Photochemical dimerizations were identified using UV-visible and FT-IR spectroscopy. Polyimide films containing cinnamate groups were irradiated by linear polarized ultra violet (LPUV) light. Schadt et al. claims that the photo-alignment results from the anisotropy depletion of the cinnamate side chains as a consequence of the (2+2) cycloaddition reactions. The photo-aligned polyimide induces the orientation of nematic liquid crystals perpendicular to the polarization axis. However, the un-reacted photo-sensitive functional groups generate problems such as image sticking and reduced contrast ratio. Voltage holding ratio and photo-fading observed from photo-alignment layer can be dramatically improved by annihilation process of remnant photoreactive groups.

Size removal on polyester fabrics by plasma source ion implantation device

Plasma treatment was evaluated as an alternative clean desizing technology in this work. As indicated by weight loss, O2 plasma treatment efficiently removed sizing agents such as polyvintyl alcohol (PVA), polyacrylic acid esters and their mixture (MIX) on polyethylene terephthalate (PET) fabrics. SEM pictures of the plasma treated samples directly proved the disappearance of the sizing agents. XPS analysis showed apparent changes in chemical composition and functional groups of the PET surface after O2 plasma treatment. Carbon content decreased due to the removal of sizing agents while oxygen content increased. O2 plasma treatment also increased hydrophilic functional groups of sizing agents, which is confirmed by C1s and O1s deconvolution analyses. After O2 plasma treatment, the PET fabric was subjected to conventional desizing process at different temperatures. Except for the PET fabric sized with PVA, plasma-treated fabrics showed more efficient desizing results when compared with untreated fabrics. Furthermore, the desizing effluent from the treated fabric gave lower TOC, COD and BOD values.

Percutaneous insertion of Zilver stent in malignant biliary obstruction

BACKGROUND

We evaluated the clinical efficacy and technical feasibility of the percutaneously inserted self-expandable nitinol stent (Zilver stent) for palliation of malignant biliary obstruction.

METHODS

Seventeen patients with malignant tumors involving the intra- or extrahepatic bile duct who presented with obstructive jaundice underwent percutaneous insertion of a self-expandable nitinol stent. We retrospectively reviewed the hospital records of patients and evaluated the technical feasibility on stent placement, complications, patient survival, and duration of stent patency.

RESULTS

Percutaneous biliary stenting with 27 Zilver stents was performed in 17 patients with malignant biliary obstruction. Technical success was 95%. Malposition of the stent was encountered in one patient. Minor technical problems were encountered in two patients: the introducer tip was broken during stent insertion, so endoscopic removal was done. Mean follow-up period for the 17 patients was 182 days (range 29-485 days): nine patients died of progressive disease at a mean follow-up of 151 days (range 61-371days) after stent insertion and eight patients remained alive at the final follow-up of 216 days (range 29-485 days). The median survival period for all patients was 277 days. The stent occlusion rate was 26% and the mean patency period was 280 days. In five patients, seven stents were obstructed by tumor ingrowth and overgrowth. Stent patency rates were 100%, 100%, 75%, 61%, and 41% at 1, 2, 3, 6, and 12 months, respectively. A late complication, erosive bleeding of the hepatic artery by the stent, developed in one patient.

CONCLUSION

Percutaneous biliary stenting using the nitinol stent is technically feasible and safe and clinically efficacious treatment for malignant biliary obstruction, even with a minor technical problem during stent insertion.

Intracranial xanthoma: long-term follow-up MR findings

SUMMARY

We report the serial MR findings and histologic features of intracerebral xanthoma in a patient with hyperlipidemia. MR imaging revealed nodule formations with variable degrees of edema and enhancement in the perivascular spaces. In some lesions, high-signal-intensity foci were observed on unenhanced T1-weighted images, which suggest lipid contents of the lesion.

Morphology and metabolism of Ba-alginate encapsulated hepatocytes with galactosylated poly(allyl amine) and poly(vinyl alcohol) as extracellular matrices

Lactobionic acid, bearing a beta -galactose group, was coupled with poly(allyl amine) to provide synthetic extracellular matrices together with poly(vinyl alcohol) (PVA). The hepatocytes were encapsulated in Ba-alginate capsules with galactosylated poly(allyl amine) (GA) and PVA as extracellular matrices. From microscopic observation, it was revealed that the microcapsule prepared has a highly porous structure with interconnected pores and pore sizes ranging between 50-150 nm on both the surface and the cross-section. It was found, from the permeability experiment of microcapsules using FITC-dextrans with different molecular weights, that the capsule has a molecular weight cut off (MWCO) of 120 kDa, showing the potential that it can function as an immunoprotecting wall. The hepatocytes, cultured with GA and PVA in the core of the microcapsule, rapidly aggregated within a day, thus resulting in good metabolic functions such as albumin synthesis and ammonia removal.

Functional and genetic assessment of IFN-gamma receptor in patients with clinical tuberculosis

OBJECTIVE

The molecular basis of the genetic vulnerability underlying the most common form of clinical tuberculosis (TB) remains largely unknown. We speculated that mild genetic defects in the interferon-gamma (IFN-gamma) signalling pathway caused a subtle functional impairment of IFN-gamma which would explain susceptibility to Mycobacterium tuberculosis in clinical TB.

DESIGN

A case-control study.

RESULTS

We evaluated functional responsiveness to IFN-gamma in monocytes from patients with clinical TB (n = 10), and analysed the genetic sequences of the IFN-gamma receptor 1 (IFN-gammaR1) and STAT1 genes in patients with disseminated TB (n = 18). IFN-gamma stimulated an increase in the expression of HLA-DR and CD64 on monocytes of both controls and patients; the rate of increase in expression was the same in both groups. Treatment with IFN-gamma before lipopolysaccharide (LPS) stimulation further increased tumour necrosis factor-alpha (TNF-alpha) production as compared to TNF-alpha production with LPS stimulation alone; the rate of increase in TNF-alpha production was the same in both groups. The known mutations in the coding sequences of the IFN-gammaR1 and STAT1 genes were not found in the patients with disseminated tuberculosis.

CONCLUSION

These results suggest that impairment of the IFN-gamma signalling pathway did not account for cases of clinical TB in this study.

Gene expression profile analysis in human hepatocellular carcinoma by cDNA microarray

We performed gene expression profiling of normal and hepatocellular carcinoma (HCC) liver tissues using a high-density microarray that contained 3,063 human cDNA. The results of a microarray hybridization experiment from eight different HCC tissues were analyzed and classified by the Cluster program. Among these differentially-expressed genes, the galectin-3, serine/threonine kinase SGK, translation factor eIF-4A, -4B, -3, fibroblast growth factor receptor, and ribosomal protein L35A were up-regulated; the mRNAs of Nip3, decorin, and the insulin-like growth factor binding protein-3 were down-regulated in HCC. The differential expression of these genes was further confirmed by an RT-PCR analysis. In addition, our data suggest that the gene expression profile of HCC varies according to the histological types.

Diffusion-weighted magnetic resonance imaging in Wernicke's encephalopathy

OBJECTIVE

To report diffusion-weighted imaging (DWI) findings and postulate the pathogenic mechanism of Wernicke's encephalopathy (WE).

PATIENT

A 47-year-old-woman presented with altered consciousness, ophthalmoplegia, and ataxia. DWI revealed the abnormal signal changes in periaqueductal gray matter, mamillary bodies and bilateral medial thalami. Apparent diffusion coefficient (ADC) map revealed the high signal intensity lesions in bilateral medial thalami, suggestive of vasogenic edema. The abnormal signal intensity lesions disappeared on follow-up imaging with clinical improvement.

CONCLUSIONS

Vasogenic edema plays an important role in the pathogenesis of WE and can be reversed by proper management. DWI findings in the early stage of WE may provide useful information about the prognosis.

Tumor apoptosis in cervical cancer: its role as a prognostic factor in 42 radiotherapy patients

To investigate tumor apoptosis as a prognostic factor for outcome following radiation therapy, comparisons were made of apoptotic index (AI) as a predictor of short- vs. long-term response and pretreatment vs. radiation-induced apoptosis. Forty-two patients with proven squamous cell carcinoma of the uterine cervix were treated by radiation alone. Apoptosis was measured by light microscopic observation of hematoxylin and eosin-stained sections from biopsies taken before treatment and 4 and 24 hr after 2 Gy. Patients were evaluated at the end of the external radiation for determination of short-term response and for long-term outcome as well (median follow-up of 27 months). Patients with high spontaneous AI showed poor short-term response, local control, and survival. The significance of AI as a predictor of short-term response was lost after allowing for differences in tumor size. The positive predictive value of AI for local control and survival was independent of tumor size and stage. High AI was associated with poor local control and long-term prognosis in advanced squamous cell carcinoma of the cervix. The in vivo radiation-induced AI after 4 or 24 hr did not predict radiation therapy outcome.

Successful resection of cecal hepatic metastasis extending into the right side of the heart under cardiopulmonary bypass

Resection is the best hope for the cure of colorectal metastasis to the liver. However, surgery is indicated for only a few patients, especially those who have major vascular involvement. We report a 55-year-old woman with a liver metastasis from the cecum that showed a tumor thrombus in the right side of the heart. She had undergone laparoscopic right hemicolectomy for cecal cancer 6 months before, and presented with a palpable mass in the epigastrium. Abdominal ultrasonography, computed tomography, hepatic angiogram, and echocardiography showed a huge mass on the left lobe of the liver, with a tumor thrombus which extended to the right ventricle through the left hepatic vein and inferior vena cava. Tumor thrombectomy, through a right atriotomy, was success-fully performed under cardiopulmonary bypass, followed by left hepatic lobectomy. The patient's postoperative course was uneventful.

Immunization of cultured juvenile rockfish Sebastes schlegeli against Microcotyle sebastis (Monogenea)

To determine whether immunization with Microcotyle sebastis antigen could induce protection against the parasite's establishment, naive juvenile rockfish were immunized by injection or immersion with whole worm antigen of M. sebastis. The infestation intensities of immunized groups following a challenge (2 wk after boosting) with 5000 M. sebastis eyed-eggs were significantly lower than those of control groups, when determined 7 wk postinfection. The fish in the groups boosted with M. sebastis antigen showed stronger protection than unboosted groups. The control group injected with FCA only showed a significantly smaller number of worms than the control group, which was immersed in PBS containing seawater. The results strongly suggest that both specific and nonspecific immune factors participate in the protection of rockfish against M. sebastis establishment.

A simple method of reduction malarplasty

The Oriental face is generally mesocephalic: short and wide. Thus the prominent zygoma in relation to a flat nose will make the face seem flatter. The unfavorable social connotations associated with a prominent zygoma are a reality in Korea. Reduction will not only relieve the patient of such psychological burdens but also afford a face with a cheerful and youthful appearance. Thus not a few patients seek surgery for these reasons. Previously, chiseling or burring of the zygoma body and arch was frequently used for zygoma reduction but was usually less than effective in reducing the wide face. Segmental osteotomy and repositioning of the arch by means of a bicoronal approach was another method, but this involved an extensive operation and left a long visible scar. We left that these methods were less than ideal as aesthetic procedures. A simple and yet effective method of reducing the prominent zygoma was needed. Reduction of the prominent zygoma was performed in 26 patients by shaving the zygoma body and displacing the zygomatic arch inwardly after two-point fracturing, greenstick fracture anteriorly, and complete osteotomy posteriorly by means of a small preauricular and upper buccal sulcus incision. We obtained satisfactory results using the relatively simple procedure. The advantages of our technique are as follows: (1) there is a small skin incision and resulting inconspicuous scar, (2) the technique is simple and effective, (3) there is no use of foreign bodies such as wires on miniplates, and (4) there is less postoperative discomfort.

A simple method for detecting human polyomavirus DNA in urine by the polymerase chain reaction

In order to develop a simple and sensitive method for detecting human polyomavirus DNA in the urine of patients by the polymerase chain reaction (PCR), it was found that the viral DNA could be released from urine by proteinase K and then amplified by PCR directly, without additional treatment such as ultracentrifugation or DNA extraction. Direct PCR amplification of viral DNA from urine was volume limited and 5 microliters of urine appeared to be the optimum amount for direct PCR amplification. When the urine volume was greater than 10 microliters, the results of PCR were inconsistent. However, the urine volume could be increased after dialysis to remove possible inhibitor(s) which may interfere with PCR. Direct PCR amplification of patient urine is convenient and eliminates several steps which can cause loss of DNA from the sample.

A hospital-based, case-control study of risk factors for hemorrhagic fever with renal syndrome in soldiers of the armed forces of the Republic of Korea

A hospital-based, case-control study was conducted to measure risk factors for hemorrhagic fever with renal syndrome in Korean soldiers. Between October 1989 and January 1992, 196 cases and 295 controls were admitted into the study. Information was collected on behavioral and environmental variables, and the data were analyzed by multiple logistic regression. The strongest risk factors were seeing Apodemus in the area (odds ratio [OR] = 4.9), living in a primitive dwelling such as a lean-to (OR = 3.9), and being exposed to dust (OR = 3.7). The most protective factors were living in barracks (OR = 0.3-0.5) and self-reported use of any insecticide or insect repellent (OR = 0.5).

The results of radiation therapy in advanced carcinoma of the lung in the Beijing region of China

From 1958 to 1973, 682 patients with lung cancer were treated by radiation therapy in the Cancer Institute, Chinese Academy of Medical Sciences, Beijing, China. The clinical presentation, sex, age, histology and stage and palliative effects of radiation therapy were reported. The 1-, 3- and 5-year survival rates were 40.62, 8.94 and 3.81%, respectively. The prognostic factors such as staging, histology, combination with chemotherapy and response of tumours are discussed. The causes of failure are also analysed. It is suggested that improving the local control rate of squamous cell carcinoma would increase the survival rate.