Resveratrol prevents renal lipotoxicity and inhibits mesangial cell glucotoxicity in a manner dependent on the AMPK-SIRT1-PGC1α axis in db/db mice

AIMS/HYPOTHESIS

Many of the effects of resveratrol are consistent with the activation of AMP-activated protein kinase (AMPK), silent information regulator T1 (SIRT1) and peroxisome proliferator-activated receptor (PPAR)γ co-activator 1α (PGC-1α), which play key roles in the regulation of lipid and glucose homeostasis, and in the control of oxidative stress. We investigated whether resveratrol has protective effects on the kidney in type 2 diabetes.

METHODS

Four groups of male C57BLKS/J db/m and db/db mice were used in this study. Resveratrol was administered via gavage to diabetic and non-diabetic mice, starting at 8 weeks of age, for 12 weeks.

RESULTS

The db/db mice treated with resveratrol had decreased albuminuria. Resveratrol ameliorated glomerular matrix expansion and inflammation. Resveratrol also lowered the NEFA and triacylglycerol content of the kidney, and this action was related to increases in the phosphorylation of AMPK and the activation of SIRT1-PGC-1α signalling and of the key downstream effectors, the PPARα-oestrogen-related receptor (ERR)-1α-sterol regulatory element-binding protein 1 (SREBP1). Furthermore, resveratrol decreased the activity of phosphatidylinositol-3 kinase (PI3K)-Akt phosphorylation and class O forkhead box (FOXO)3a phosphorylation, which resulted in a decrease in B cell leukaemia/lymphoma 2 (BCL-2)-associated X protein (BAX) and increases in BCL-2, superoxide dismutase (SOD)1 and SOD2 production. Consequently, resveratrol reversed the increase in renal apoptotic cells and oxidative stress, as reflected by renal 8-hydroxy-deoxyguanosine (8-OH-dG), urinary 8-OH-dG and isoprostane concentrations. Resveratrol prevented high-glucose-induced oxidative stress and apoptosis in cultured mesangial cells through the phosphorylation of AMPK and activation of SIRT1-PGC-1α signalling and the downstream effectors, PPARα-ERR-1α-SREBP1.

CONCLUSIONS/INTERPRETATION

The results suggest that resveratrol prevents diabetic nephropathy in db/db mice by the phosphorylation of AMPK and activation of SIRT1-PGC-1α signalling, which appear to prevent lipotoxicity-related apoptosis and oxidative stress in the kidney.

Hepatocellular carcinoma treated with percutaneous radio-frequency ablation: evaluation with follow-up multiphase helical CT

PURPOSE

To determine serial changes in hepatocellular carcinomas (HCCs) treated with percutaneous radio-frequency (RF) ablation at long-term follow-up multiphase helical computed tomography (CT).

MATERIALS AND METHODS

There were 43 nodular HCCs in 40 patients at follow-up CT performed not less than 12 months after RF ablation. All patients underwent follow-up multiphase helical CT immediately, 1 month, and then every 3 months after percutaneous RF ablation. The serial changes in attenuation, enhancement pattern, shape, other findings, and volume of the ablated lesions were analyzed at follow-up CT.

RESULTS

Thirty-eight (88%) of 43 ablated lesions were of low attenuation, with absence of contrast material enhancement at immediate and 1-month follow-up CT, which is suggestive of successful treatment. The remaining five lesions (12%) showed peripheral nodular enhancement, suggesting residual viable tumor. Compared with volume changes at immediate follow-up CT, the mean percentages of volume change at 1, 4, 10, 16, and 19 months were 79%, 50%, 27%, 11%, and 6%, respectively. Of 43 ablated lesions, 24 (56%) were mostly round at immediate CT and remained unchanged at subsequent follow-up CT. Peripheral rim enhancement was seen in 34 (79%) of 43 lesions at immediate CT but resolved in all 34 lesions at 1-month follow-up CT. Other associated findings included iatrogenic arteriovenous shunt in 10 patients, perihepatic hemorrhage in three, and pneumothorax in one.

CONCLUSION

Follow-up multiphase helical CT of HCCs treated with percutaneous RF ablation showed variable findings in the treated lesions and surrounding liver parenchyma.

Protection of ischemic hippocampal neurons by ginsenoside Rb1, a main ingredient of ginseng root

Our previous study showed that the oral administration of red ginseng powder before but not after transient forebrain ischemia prevented delayed neuronal death in gerbils, and that a neuroprotective molecule within red ginseng powder was ginsenoside Rb1. However, it remains to be clarified whether or not ginsenoside Rb1 acts directly on the ischemic brain, and the mechanism by which ginsenoside Rb1 protects the ischemic CA1 neurons is not determined. Without elucidation of the pharmacological property of ginsenoside Rb1, the drug would not be accepted as a neuroprotective agent. The present study demonstrated that the intracerebroventricular infusion of ginsenoside Rb1 after 3.5 min or 3 min forebrain ischemia, precluded significantly the ischemia-induced shortening of response latency in a step-down passive avoidance task and rescued a significant number of hippocampal CA1 neurons from lethal ischemic damage. The intracerebroventricular infusion of ginsenoside Rb1 did not affect hippocampal blood flow or hippocampal temperature except that it caused a slight increase in hippocampal blood flow at 5 min after transient forebrain ischemia. Furthermore, ginsenoside Rb1 at concentrations of 0.1-100 fg/ml (0.09-90 fM) rescued hippocampal neurons from lethal damage caused by the hydroxyl radical-promoting agent FeSO4 in vitro, and the Fenton reaction system containing p-nitrosodimethylaniline confirmed the hydroxyl radical-scavenging activity of ginsenoside Rb1. These findings suggest that the central infusion of ginsenoside Rb1 after forebrain ischemia protects hippocampal CA1 neurons against lethal ischemic damage possibly by scavenging free radicals which are overproduced in situ after brain ischemia and reperfusion. The present study may validate the empirical usage of ginseng root over thousands of years for the prevention of cerebrovascular diseases.

Protein import channel of the outer mitochondrial membrane: a highly stable Tom40-Tom22 core structure differentially interacts with preproteins, small tom proteins, and import receptors

The preprotein translocase of the yeast mitochondrial outer membrane (TOM) consists of the initial import receptors Tom70 and Tom20 and a approximately 400-kDa (400 K) general import pore (GIP) complex that includes the central receptor Tom22, the channel Tom40, and the three small Tom proteins Tom7, Tom6, and Tom5. We report that the GIP complex is a highly stable complex with an unusual resistance to urea and alkaline pH. Under mild conditions for mitochondrial lysis, the receptor Tom20, but not Tom70, is quantitatively associated with the GIP complex, forming a 500K to 600K TOM complex. A preprotein, stably arrested in the GIP complex, is released by urea but not high salt, indicating that ionic interactions are not essential for keeping the preprotein in the GIP complex. Under more stringent detergent conditions, however, Tom20 and all three small Tom proteins are released, while the preprotein remains in the GIP complex. Moreover, purified outer membrane vesicles devoid of translocase components of the intermembrane space and inner membrane efficiently accumulate the preprotein in the GIP complex. Together, Tom40 and Tom22 thus represent the functional core unit that stably holds accumulated preproteins. The GIP complex isolated from outer membranes exhibits characteristic TOM channel activity with two coupled conductance states, each corresponding to the activity of purified Tom40, suggesting that the complex contains two simultaneously active and coupled channel pores.

Detection of hepatocellular carcinomas and dysplastic nodules in cirrhotic livers: accuracy of helical CT in transplant patients

OBJECTIVE

The purpose of this study was to evaluate the diagnostic efficacy of three-phase helical dynamic CT in the detection and characterization of hepatocellular carcinomas and dysplastic nodules in cirrhotic livers.

SUBJECTS AND METHODS

Three-phase helical dynamic CT in 41 patients with liver cirrhosis was evaluated prospectively before orthotopic liver transplantation. The numbers of hepatocellular carcinomas and dysplastic nodules were assessed in the explanted livers and compared with pretransplantation CT findings.

RESULTS

Examination of the explanted livers revealed 21 hepatocellular carcinomas in 15 patients and 23 dysplastic nodules in 10 patients. The size of the hepatocellular carcinomas was 0.6-5. 0 cm (mean, 1.9 cm), and that of the dysplastic nodules was 0.7-2.0 cm (mean, 1.0 cm). The use of helical dynamic CT enabled detection of 15 of 21 hepatocellular carcinomas (sensitivity, 71%) and nine of 23 dysplastic nodules (sensitivity, 39%). Patient sensitivity and specificity in the detection of hepatocellular carcinomas were 80% (12/15) and 96% (25/26), respectively, and for dysplastic nodules, 50% (5/10) and 97% (30/31), respectively.

CONCLUSION

Three-phase helical dynamic CT is relatively insensitive for detection of hepatocellular carcinomas and dysplastic nodules in cirrhotic livers, especially for dysplastic nodules and hepatocellular carcinomas smaller than 2 cm.

Radiologic spectrum of cholangiocarcinoma: emphasis on unusual manifestations and differential diagnoses

Most cholangiocarcinomas are ductal adenocarcinomas that arise from both intra- and extrahepatic bile duct epithelium, and their typical growth pattern can be classified as exophytic, infiltrative, polypoid, or a combination of these. Those of unusual histologic type (eg, mucin-hypersecreting cholangiocarcinoma, squamous adenocarcinoma, biliary cystadenocarcinoma, and mucinous carcinoma) show a growth pattern different from that of the typical ones (ie, ductal). Cholangiocarcinomas frequently develop in patients with any of a variety of preexisting bile duct diseases, some of which are considered precursors of cholangiocarcinoma (eg, biliary lithiasis, clonorchiasis, recurrent pyogenic cholangitis, and primary sclerosing cholangitis). Some bulky hepatic tumors of either primary or secondary origin mimic exophytic peripheral cholangiocarcinoma. Some variants of hepatocellular carcinoma, such as sclerosing, fibrolamellar, and cholangiohepatocellular carcinoma, resemble exophytic peripheral cholangiocarcinoma, while that with intraductal growth resembles polypoid cholangiocarcinoma. Among benign bile duct diseases, tumorous conditions (eg, benign biliary tumors) may mimic polypoid cholangiocarcinoma, whereas benign stricture of various causes (eg, cholangitides, traumatic and postsurgical sequelae, chronic pancreatitis, papillary stenosis) usually mimics infiltrative cholangiocarcinoma.

Inhibitory patterning of the anterior neural plate in Xenopus by homeodomain factors Dlx3 and Msx1

Patterning of the embryonic ectoderm is dependent upon the action of negative (antineural) and positive (neurogenic) transcriptional regulators. Msx1 and Dlx3 are two antineural genes for which the anterior epidermal-neural boundaries of expression differ, probably due to differential sensitivity to BMP signaling in the ectoderm. In the extreme anterior neural plate, Dlx3 is strongly expressed while Msx1 is silent. While both of these factors prevent the activation of genes specific to the nascent central nervous system, Msx1 inhibits anterior markers, including Otx2 and cement gland-specific genes. Dlx3 has little, if any, effect on these anterior neural plate genes, instead providing a permissive environment for their expression while repressing more panneural markers, including prepattern genes belonging to the Zic family and BF-1. These properties define a molecular mechanism for translating the organizer-dependent morphogenic gradient of BMP activity into spatially restricted gene expression in the prospective anterior neural plate.

Ginseng root prevents learning disability and neuronal loss in gerbils with 5-minute forebrain ischemia

The present study was designed to investigate the possible neuroprotective activity of ginseng roots in 5-min ischemic gerbils using a step-down passive avoidance task and subsequent neuron and synapse counts in the hippocampal CA1 region. The following drugs were administered for 7 days before the induced ischemia: red ginseng powder (RGP), crude ginseng saponin (CGS), crude ginseng non-saponin (CGNS), and pure ginsenosides Rb1, Rg1 and Ro. Oral administration of RGP significantly prevented the ischemia-induced decrease in response latency, as determined by the passive avoidance test, and rescued a significant number of ischemic hippocampal CA1 pyramidal neurons in a dose-dependent manner. Intraperitoneal injections of CGS exhibited a similar neuroprotective effect. CGNS had a significant but less potent protective effect against impaired passive avoidance task and degeneration of hippocampal CA1 neurons. Ginsenoside Rb1 significantly prolonged the response latency of ischemic gerbils and rescued a significant number of ischemic CA1 pyramidal neurons, whereas ginsenosides Rg1 and Ro were ineffective. Postischemic treatment with RGP, CGS or ginsenoside Rb1 was ineffective. The neuroprotective activities of RGP, CGS and ginsenoside Rb1 were confirmed by electron microscopy counts of synapses in individual strata of the CA1 field of ischemic gerbils pretreated with the drugs. These findings suggest that RGP and CGS are effective in the prevention of delayed neuronal death, and that ginsenoside Rb1 is one of the neuroprotective molecules within ginseng root.

Radiologic spectrum of intraductal papillary mucinous tumor of the pancreas

"Intraductal papillary mucinous tumor" is now the preferred term to describe a spectrum of proliferation of the pancreatic ductal epithelium. The tumor produces an excessive amount of mucin and results in progressive dilation of the main pancreatic duct or cystic dilation of the branch ducts, depending on the location of the tumor. This tumor is small and localized in a segment of the main pancreatic duct or in branch ducts, particularly in the branch ducts of the uncinate process, but it may also be diffuse, involving a wide area of the pancreatic ducts. Excessive mucin may impede the pancreatic duct flow and, in turn, produce symptoms of chronic pancreatitis. The following findings are seen on imaging studies: lobulated multicystic dilatation of the branch ducts, diffuse dilatation of the main pancreatic duct, intraductal papillary tumors, elongated or globlike mucous plugs in the dilated ducts, and bulging of the papilla into the duodenal lumen. The diagnosis is suggested at ultrasonography, computed tomography, or magnetic resonance cholangiopancreatography. Endoscopic retrograde cholangiopancreatography is the imaging modality of choice for the diagnosis, because it depicts the communication between the cystically dilated branch ducts and the diffusely dilated main pancreatic duct, as well as intraductal papillary tumor and mucous plugs.

The crystal structure of an Fe-superoxide dismutase from the hyperthermophile Aquifex pyrophilus at 1.9 A resolution: structural basis for thermostability

Superoxide dismutase (SOD) from Aquifex pyrophilus, a hyperthermophilic bacterium, is an extremely heat-stable enzyme that maintains about 70% of its activity after heat treatment for 60 minutes at 100 degrees C. To understand the molecular basis of thermostability of this enzyme, we have determined the crystal structure of A. pyrophilus superoxide dismutase (Ap SOD), an Fe containing homotetrameric enzyme, at 1.9 A resolution, and compared it with SOD structures from a mesophile and a thermophile, and other enzyme structures from other hyperthermophiles. The structure has been refined to a crystallographic R-factor (I > 2sigma) of 17.0% and R-free (I > 2sigma) of 19.9%. While the overall structure of the Ap SOD monomer is similar to the other SODs, significant conformational differences are observed in a highly variable loop region and the C-terminal helix. The conformational differences in these regions alter the subunit arrangement of this enzyme and generate a very compact tetramer. Structural comparisons of three SODs have revealed that Ap SOD has some stabilizing features at both the tertiary and the quaternary structural level: The Ap SOD monomer contains a large number of ion-pairs and the Ap SOD tetramer has a dramatically increased buried surface area per monomer. Comparisons of the Ap SOD structure with that of other known enzymes from hyperthermophiles reveal that the increased number of intrasubunit ion-pairs is a common feature.

Fingertip replantations: clinical evaluation of 135 digits

From July 1985 to February 1993, 135 digits in 119 patients with complete amputations at or distal to the distal interphalangeal joint (zone I for amputations distal to the nail base of zone II for amputations between the distal interphalangeal joint and the nail base) were replanted using a microsurgical technique at Korea University Guro Hospital. Because of the high social value placed on body form and function, the indication for replantation was extended to cases with severe soft-tissue injuries and attempted replantation as a routine procedure in nearly all distal amputation cases. The overall survival rate was 78 percent, with the survival rate for zone I being 70 percent and that for zone II reaching 86 percent. Even in cases with severe soft-tissue injury, the survival rate was high, with viability in avulsion injuries and crush injuries reaching 75 percent each. The most common type of vascular repair in zone I cases was revascularization of one artery only and no vein repair (87 percent). Of these cases, interpositional vein grafts were used in 65 percent. In zone II cases, the most common combination repair was one artery and one vein anastomosis (70 percent), with interpositional vein grafts for arterial anastomosis in 49 percent; most of the venous repair was feasible by the direct method (78 percent). The follow-up period ranged from 1 month to 5 years with a mean of 14.8 months; 52 patients were followed-up for more than 6 months. In 52 long-term follow-up patients, the average two-point discrimination was 8 mm. Patient satisfaction, aesthetically and functionally, was high (91 percent).

Conspicuity of hepatocellular nodular lesions in cirrhotic livers at ferumoxides-enhanced MR imaging: importance of Kupffer cell number

PURPOSE

To correlate the conspicuity of hepatocellular carcinomas and dysplastic nodules on ferumoxides-enhanced magnetic resonance (MR) images with the number of Kupffer cells in the hepatic lesions, as compared with that in background liver in histopathologic findings.

MATERIALS AND METHODS

Sixty-nine histopathologically proved moderately or poorly differentiated hepatocellular carcinomas, 10 well-differentiated hepatocellular carcinomas, and 19 dysplastic nodules were retrospectively studied in 68 patients with cirrhosis who underwent ferumoxides-enhanced MR imaging. The contrast-to-noise ratio between the nodules and surrounding parenchyma was calculated at T2-weighted fast spin-echo imaging, and the difference in the number of Kupffer cells between the nodules and surrounding hepatic tissue was calculated histopathologically. The results of MR imaging and histopathologic examination were correlated.

RESULTS

All 69 moderately or poorly differentiated hepatocellular carcinomas had high contrast-to-noise ratios at MR imaging and large differences in the number of Kupffer cells. Six of the 10 well-differentiated hepatocellular carcinomas had contrast-to-noise ratios of zero or nearly zero, and five of these had little difference in the number of Kupffer cells. All 19 dysplastic nodules had contrast-to-noise ratios of zero or nearly zero, and there were virtually no differences in the number of Kupffer cells.

CONCLUSION

Hepatocellular nodule conspicuity at ferumoxides-enhanced MR imaging depends on differences in the number of Kupffer cells within a nodule and the surrounding cirrhotic liver; moderately or poorly differentiated hepatocellular carcinomas can be distinguished from well-differentiated hepatocellular carcinomas and dysplastic nodules.

Detection of hepatocellular carcinomas and dysplastic nodules in cirrhotic liver: accuracy of ultrasonography in transplant patients

The purpose of this study was to assess the usefulness of ultrasonography in the detection of hepatocellular carcinomas and dysplastic nodules in patients with liver cirrhosis. Pretransplantation sonograms in 52 patients with liver cirrhosis who underwent orthotopic liver transplantation were evaluated retrospectively. The numbers of hepatocellular carcinomas and dysplastic nodules were assessed in the explanted liver specimens and compared with pretransplantation ultrasonographic results. Eighteen hepatocellular carcinomas in 16 patients and 20 dysplastic nodules in 11 patients were present in the explanted livers. The size of hepatocellular carcinomas ranged from 0.6 to 5.0 cm (mean, 2.1 cm) in diameter, and that of dysplastic nodules ranged from 0.5 to 1.7 cm (mean, 1.0 cm) in diameter. Pretransplantation ultrasonography enabled detection of 6 of 18 hepatocellular carcinoma and 0 of 20 dysplastic nodule lesions; lesion detection sensitivity for hepatocellular carcinomas and dysplastic nodules was 33% and 0%, respectively. Patient sensitivity and specificity for hepatocellular carcinomas were 38% (6 of 16) and 92% (33 of 36), and those for dysplastic nodules were 0% and 95% (39 of 41), respectively. On the basis of our results, ultrasonography is insensitive for detection of hepatocellular carcinomas and dysplastic nodules in patients with advanced liver cirrhosis.

Hepatocellular carcinoma: are combined CT during arterial portography and CT hepatic arteriography in addition to triple-phase helical CT all necessary for preoperative evaluation?

PURPOSE

To determine whether the combination of CT during arterial portography (CTAP) and CT hepatic arteriography (CTHA) provides an added benefit to triple-phase helical CT (THCT) alone in the preoperative evaluation of hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

Fifty-two consecutive patients with pathologically proved HCC underwent THCT (hepatic arterial, portal venous, and delayed phases) and combined CTAP and CTHA. Two radiologists reviewed the images in three sessions: first the THCT images alone, then with the CTAP images, and finally all three sets of images.

RESULTS

There were 73 pathologically confirmed HCCs. Among 72 lesions considered as HCC at THCT, 69 were proved to be HCCs. Of the additional 37 nodules interpreted as HCC at CTAP, only one was confirmed as such. Among the additional 20 lesions presumed to be HCC at combined CTAP and CTHA, only two were proved to be HCCs. The sensitivity was 94% (69 of 73 lesions) at THCT, 96% (70 of 73) with additional CTAP, and 97% (71 of 73) with all three modalities. The positive predictive value was 96% (69 of 72) at THCT, 65% (70 of 107) with additional CTAP, and 80% (71 of 89) with all three modalities.

CONCLUSION

The use of CTAP and CTHA, in addition to being invasive and costly, resulted in an unacceptably high false-positive rate without a substantial increase in sensitivity. Therefore, CTAP and CTHA are not recommended for preoperative evaluation of HCC; THCT alone is preferred.

Oriental cholangiohepatitis: pathologic, clinical, and radiologic features

Oriental cholangiohepatitis, an endemic disease in Southeast Asia, is characterized by recurrent attacks of abdominal pain, fever, and jaundice. Pathologically, the intra- and extrahepatic ducts are dilated and contain soft, pigmented stone and pus. There is proliferation of bile ducts and infiltration of inflammatory cells along the periportal spaces and hepatic parenchyma. Localized intrahepatic segmental ductal stenosis may be present, especially in the lateral segment of the left lobe or posterior segment of the right hepatic lobe. The cause of the disease is not known, but associations with clonorchiasis, ascariasis, and nutritional deficiency have been suggested. Sonographic and CT findings include intra- or extrahepatic duct stones, dilatation of the extrahepatic duct with relatively mild or no dilatation of the intrahepatic ducts, localized dilatation of the lobar or segmental bile ducts, increased periportal echogenicity, segmental hepatic atrophy, and gallstones. Cholangiographic findings include bile duct stones; disproportionately severe dilatation of the extrahepatic ducts with mild or no dilatation of the intrahepatic ducts; and focal strictures, acute peripheral tapering, straightening, rigidity, decreased arborization, and an increased branching angle of the intrahepatic bile ducts.

Small bowel obstruction: sonographic evaluation

Results of 54 sonographic examinations of patients referred for suspected or known small intestinal obstruction were retrospectively correlated with surgical findings, and the diagnostic value of sonography regarding presence, level, and cause of obstruction was compared with that of plain abdominal radiography. The diagnosis of obstruction was correct in 89% of cases with sonography and in 71% with plain radiography. The level of obstruction was correctly predicted in 76% of cases with sonography and in 51% with plain radiography. The cause of obstruction was correctly predicted in 20% of cases with sonography and in 2% with plain radiography. The authors conclude that use of sonography in evaluating patients with bowel obstruction may be helpful in confirmation of the presence of obstruction, in determination of the level of obstruction, and in identification of the cause of obstruction.

Biliary cystadenoma and cystadenocarcinoma: CT and sonographic findings

Eight women (ages 18-65 years; mean, 47 years) with biliary cystadenoma (n = 3) or cystadenocarcinoma (n = 5) were examined with computed tomography and sonography. The appearance of the tumors varied from unilocular cystic masses to multilocular cystic masses with multiple satellite tumors, although the majority (n = 6) of tumors were single, multilocular, and cystic. Cystic areas showed attenuation numbers under +30 HU. Papillary excrescences, nodular thickening of internal septa, and mural nodules, which showed contrast enhancement, were seen in one case of cystadenoma and all five cases of cystadenocarcinoma. One cystadenoma and one cystadenocarcinoma contained calcifications. Three cases showed connection to the intrahepatic bile ducts. Biliary cystadenoma and cystadenocarcinoma should be the primary diagnostic consideration when one detects in a middle-aged woman a well-encapsulated, multilocular cystic mass connected to the biliary system or prolapsing into the bile duct.

Arsenic trioxide induces G2/M growth arrest and apoptosis after caspase-3 activation and bcl-2 phosphorylation in promonocytic U937 cells

Arsenic trioxide has recently been shown to inhibit growth and induce apoptosis in acute promyelocytic leukemia (APL), but little is known about the molecular mechanisms mediating these effects. Here we demonstrate that treatment of promonocytic U937 cells with arsenic trioxide leads to G2/M arrest which was associated with a dramatic increase in the levels of cyclin B and cyclin B-dependent kinase and apoptosis. We further show that apoptosis occurs after bcl-2 phosphorylation and caspase-3 activation followed by cleavage of PARP and PLC-gamma1 degradation and DNA fragmentation. The arsenic trioxide-induced apoptosis could be blocked by the protein synthesis inhibitor cycloheximide. In addition, pretreatment of U937 cells with the DNA polymerase inhibitor aphidicolin also blocked apoptosis, but did not cause the arrest of cells in the G2/M phase. The findings suggest that arsenic trioxide exerts its growth-inhibitory effects by modulating expression and/or activity of several key G2/M regulatory proteins. Furthermore, arsenic trioxide-mediated G2/M arrest correlates with the onset of apoptosis.

Mucocele of the appendix: ultrasonographic and CT findings

BACKGROUND

Mucocele of the appendix is a rare disease entity, but preoperative diagnosis is very important. With the advent of ultrasonography (US) and computed tomography (CT), it has been possible to preoperatively diagnose mucocele of the appendix. We describe the spectrum of US and CT findings of mucocele of the appendix and the differential points from mimicking diseases.

METHODS

We evaluated 17 patients with pathologically proven mucocele of the appendix by using US and CT. Pathologic diagnoses of 17 patients were mucinous cystadenoma in 11 patients, mucinous cystadenocarcinoma in two, and mucosal hyperplasia in four. We analyzed morphologic characteristics of mucocele of the appendix at US and CT.

RESULTS

The typical US finding were a cystic mass with variable internal echogenicity, layered wall, and calcification in the wall. The CT finding was a well-encapsulated cystic mass with a wall of variable thickness. Both cases with focal nodular solid enhancing portion in the wall on CT were pathologically proven as mucinous cystadenocarcinoma.

CONCLUSION

US and CT were useful methods in diagnosing mucocele of the appendix and differentiating this condition from mimicking diseases. Nodular enhancing lesion in the wall of the mucocele may be a finding suggestive of malignant cause of mucocele.

Dysplastic nodules in liver cirrhosis: evaluation of hemodynamics with CT during arterial portography and CT hepatic arteriography

PURPOSE

To evaluate the portal and arterial blood supplies to dysplastic nodules in the cirrhotic liver with computed tomography (CT) during arterial portography (CTAP) and CT hepatic arteriography (CTHA).

MATERIALS AND METHODS

Nineteen histopathologically proved low-grade dysplastic nodules and 13 high-grade dysplastic nodules in 17 patients with liver cirrhosis were evaluated with CTAP and CTHA for the presence of portal and arterial blood supplies to the nodules. The nodules ranged from 0.4 to 4.5 cm in diameter (mean, 1.6 cm).

RESULTS

The portal supply was present in 14 of the 19 (74%) low-grade dysplastic nodules and in seven of the 13 (54%) high-grade dysplastic nodules. The hepatic arterial supply was increased in four of the 19 (21%) low-grade dysplastic nodules, present in nine (47%), and absent in six (32%). The arterial supply was increased in four of the 13 (31%) high-grade dysplastic nodules, present in four (31%), and absent in five (38%).

CONCLUSION

The portal and arterial supplies to the low- and high-grade dysplastic nodules were variable and inconsistent. Therefore, it is difficult to detect and characterize the dysplastic nodules on the radiologic images on the basis of the blood supply.

Constitutive over-expression of AtGSK1 induces NaCl stress responses in the absence of NaCl stress and results in enhanced NaCl tolerance in Arabidopsis

GSK3/shaggy-like protein kinases have been shown to play diverse roles in development and signal transduction pathways in various organisms. An Arabidopsis homologue of GSK3/shaggy-like kinase, AtGSK1, has been shown to be involved in NaCl stress responses. In order to further clarify the role of AtGSK1 in NaCl stress responses in plants, we generated transgenic Arabidopsis plants that over-expressed AtGSK1 mRNA. These plants showed enhanced resistance to NaCl stress when assayed either as whole plants or by measurement of root growth on NaCl plates. In addition, AtGSK1 transgenic plants in the absence of NaCl stress showed phenotypic changes, such as accumulation of anthocyanin, that were similar to those observed in wild-type plants under NaCl stress. Transgenic plants accumulated 30-50% more Na+ than did wild-type plants when subjected to NaCl stress, and Ca2+ content was increased by 15-30% in the transgenic plants regardless of the NaCl stress level. Northern blotting revealed that AtGSK1 over-expression induced expression of the NaCl stress-responsive genes AtCP1, RD29A and CHS1 in the absence of NaCl stress. In addition, AtCBL1 and AtCP1 were super-induced in the NaCl-stressed transgenic plants. Taken together, these results suggest that AtGSK1 is involved in the signal transduction pathway(s) of NaCl stress responses in Arabidopsis.

Clinical characteristics of patients with tuberculosis-destroyed lung

SETTING

Multicentre study.

OBJECTIVE

To define the clinical characteristics of patients with tuberculosis (TB) destroyed lung due to past TB.

DESIGN

We reviewed patients with TB-destroyed lung between May 2005 and June 2011.

RESULTS

A total of 595 patients from 21 hospitals were enrolled. The mean age was 65.63 ± 0.47 (mean ± standard error); 60.5% were male. The mean number of lobes involved was 2.59 ± 0.05. Pleural thickening was observed in 54.1% of the patients. Mean forced vital capacity (FVC), forced expiratory volume in 1 s (FEV(1)), FEV(1)/FVC, bronchodilator response and number of exacerbations per year were respectively 2.06 ± 0.03 l (61.26% ± 0.79), 1.16 ± 0.02 l (49.05% ± 0.84), 58.03% ± 0.70, 5.70% ± 0.34, and 0.40 ± 0.04. The number of lobes involved was significantly correlated with FVC and FEV(1), and with the number of exacerbations per year. Use of long-acting muscarinic antagonists or long-acting beta-2 agonists plus inhaled corticosteroids resulted in bronchodilatory effects. Multivariable regression analysis showed that age, initial FEV(1) (%) and number of exacerbations during follow-up were independent factors affecting change in FEV(1).

CONCLUSION

Decreased lung function with exacerbation, and progressive decline of FEV(1) were observed in patients with TB-destroyed lung.

NAG-1 up-regulation mediated by EGR-1 and p53 is critical for quercetin-induced apoptosis in HCT116 colon carcinoma cells

Quercetin, a flavonoid molecule ubiquitously present in nature, has multiple effects on cancer cells, including the inhibition of cell proliferation and migration. However, the responsible molecular mechanisms are not fully understood. We found that quercetin induces the expression of NAG-1 (Non-steroidal anti-inflammatory drug activated gene-1), a TGF-beta superfamily protein, during quercetin-induced apoptosis of HCT116 human colon carcinoma cells. Reporter assays using the luciferase constructs containing NAG-1 promoter region demonstrate that early growth response-1 (EGR-1) and p53 are required for quercetin-mediated activation of the NAG-1 promoter. Overexpression of NAG-1 enhanced the apoptotic effect of quercetin, but suppression of quercetin-induced NAG-1 expression by NAG-1 siRNA attenuated quercetin-induced apoptosis in HCT116 cells. Taken together, the present study demonstrates for the first time that quercetin induces apoptosis via NAG-1, providing a mechanistic basis for the apoptotic effect of quercetin in colon carcinoma cells.