Possible contribution of prior hepatitis B virus infection to the development of hepatocellular carcinoma

BACKGROUND: The prevalence of prior hepatitis B virus (HBV) infection in hepatocellular carcinoma (HCC) patients and its role in hepatocarcinogenesis are not clear. The aim of the present study is to clarify the importance of prior HBV infection in development of HCC. METHODS: Of 1288 consecutive HCC patients between January 1999 and October 2002, 1008 patients were enrolled. To determine the influence of prior HBV infection in hepatitis B surface antigen (HBsAg)-negative HCC, the prevalence of antibody to hepatitis B core antigen (anti-HBc) was examined according to age, and the clinical features were compared between the anti-HBc positive and the negative groups. RESULTS: The proportion of HBsAg-negative HCC patients, HCC patients with antibody to hepatitis C virus (anti-HCV; C-HCC) and HCC patients negative for both HBsAg and anti-HCV (nBnC-HCC), increased with age. The anti-HBc-positive rates in C-HCC patients also increased with age. Those rates in nBnC-HCC patients were >50% in all age groups. Furthermore, it was found that the anti-HBc-positive rates of these patients were higher than those of corresponding control patients. Tumor size and a positive rate for vessel involvement both in C-HCC and nBnC-HCC patients were larger and higher, respectively, in anti-HBc-positive patients compared with anti-HBc-negative patients, although the difference in nBnC-HCC did not reach statistical significance because of the small numbers. These tumor characteristics were similar to those of B-HCC patients. CONCLUSION: A possible contribution of prior HBV infection to the development of HCC is indicated.     

Improvement of rapidly progressive lupus nephritis associated MPO-ANCA with tacrolimus

A 43-year-old Japanese woman with systemic lupus erythematosus (SLE) developed rapidly progressive renal failure and nephritic syndrome with a high titer of myeloperoxidase-antineutrophil cytoplasmic antibody (MPO-ANCA). Methylprednisolone pulse therapy did not suppress the progression of renal failure. Intravenous cyclophosphamide pulse therapy and administration of azathioprine was abandoned due to adverse effects. Tacrolimus was employed as an alternative immunosuppressive therapy and was well tolerated, effectively preventing renal failure. Oral prednisolone dosage was successfully tapered without recurrence, along with decreasing titer of MPO-ANCA. Renal biopsy showed diffuse proliferative lupus nephritis (International Society of Nephrology/Renal Pathology Society class IV-G A/C) with crescent formation. These findings indicate that in addition to lupus nephritis, which usually results from deposition of circulating or locally formed immune complexes, MPO-ANCA may be involved in the pathogenesis of crescentic glomerulonephritis. Furthermore, we propose that tacrolimus is an effective immunosuppressant for MPO-ANCA-related renal crisis in diffuse proliferative lupus nephritis.     

Feasibility of structural modification of retinoid X receptor agonists to separate blood glucose-lowering action from adverse effects: studies in KKA(y) type 2 diabetes model mice

Retinoid X receptor (RXR) agonists are reported to exhibit blood glucose-lowering action owing to peroxisome proliferator-activated receptor (PPAR)/RXR or liver X receptor (LXR)/RXR activation, but may also cause adverse effects such as blood triglyceride elevation. In order to examine the feasibility of separating the glucose-lowering action from the adverse effects, we examined the effects of RXR agonists (NEt-TMN), NEt-3IB, and NEt-3IP, which have different heterodimer-activating patterns, in KKA(y) type 2 diabetes model mice. We found that NEt-3IB induced lower degrees of hepatomegaly and blood triglyceride (TG) elevation than the other RXR agonists, even though all of them showed similar blood glucose-lowering action on repeated administration. These findings indicate that structural modification of RXR agonists is a potentially effective strategy to reduce adverse effects while retaining desired activities.     

Short-term intravenous antimicrobial prophylaxis in combination with preoperative oral antibiotics on surgical site infection and methicillin-resistant <Emphasis Type="Italic">Staphylococcus aureus</Emphasis> infection in elective colon cancer surgery: Results of a prospective randomized trial

Purpose  

We performed a prospective randomized study to assess the effectiveness of short-term intravenous antimicrobial prophylaxis in combination with preoperative oral antibiotics on a surgical site and methicillin-resistant Staphylococcus aureus (MRSA) infection in elective colon cancer surgery.     

Involvement of P2X4 and P2Y12 receptors in ATP-induced microglial chemotaxis

We previously reported that extracellular ATP induces membrane ruffling and chemotaxis of microglia and suggested that their induction is mediated by the Gi/o-protein coupled P2Y(12) receptor (P2Y(12)R). Here we report discovering that the P2X(4) receptor (P2X(4)R) is also involved in ATP-induced microglial chemotaxis. To understand the intracellular signaling pathway downstream of P2Y(12)R that underlies microglial chemotaxis, we examined the effect of two phosphatidylinositol 3'-kinase (PI3K) inhibitors, wortmannin, and LY294002, on chemotaxis in a Dunn chemotaxis chamber. The PI3K inhibitors significantly suppressed chemotaxis without affecting ATP-induced membrane ruffling. ATP stimulation increased Akt phosphorylation in the microglia, and the increase was reduced by the PI3K inhibitors and a P2Y(12)R antagonist. These results indicate that P2Y(12)R-mediated activation of the PI3K pathway is required for microglial chemotaxis in response to ATP. We also found that the Akt phosphorylation was reduced when extracellular calcium was chelated, suggesting that ionotropic P2X receptors are involved in microglial chemotaxis by affecting the PI3K pathway. We therefore tested the effect of various P2X(4)R antagonists on the chemotaxis, and the results showed that pharmacological blockade of P2X(4)R significantly inhibited it. Knockdown of the P2X(4) receptor in microglia by RNA interference through the lentivirus vector system also suppressed the microglial chemotaxis. These results indicate that P2X(4)R as well as P2Y(12)R is involved in ATP-induced microglial chemotaxis.     

Cytoprotective role of mitochondrial amyloid beta peptide-binding alcohol dehydrogenase against a cytotoxic aldehyde

Recent reports on amyloid beta peptide (A beta) binding-alcohol dehydrogenase (ABAD) have revealed the link of A beta with oxidative stress derived from mitochondria in the pathogenesis of Alzheimer's disease (AD). As a novel function of ABAD, we speculate that ABAD may detoxify aldehydes, such as 4-hydroxy-2-nonenal (4-HNE). To verify this speculation, we transfected cDNA encoding ABAD into cultured cells (HeLa and SH-SY5Y), where ABAD was localized to mitochondria. ABAD-transfectants decreased the levels of externally added 4-HNE in cultured medium as detected by TLC and became resistant against external 4-HNE. Moreover, ABAD suppressed the cytotoxic effects caused by cellular 4-HNE, which were produced through excess reactive oxygen species (ROS) by treatment with an inhibitor of mitochondrial respiration, antimycin A or by adding H(2)O(2). Catabolism of 4-HNE by ABAD was inhibited by A beta, resulting in the abolishment of the cytoprotective function by ABAD against ROS. These results propose an additional role of ABAD in neural cell death in AD: ABAD detoxifies aldehydes, such as 4-HNE derived from lipid peroxides in healthy brains, and inhibited by A beta in the development of AD.     

Relationship between the size and metastasis of hepatic lymph nodes in patients with synchronous liver metastasis of colorectal cancer

BACKGROUND AND PURPOSE: This retrospective study was performed to examine the relationship between the size and metastasis of hepatic lymph node in patients with liver metastasis of colorectal cancer. PATIENTS AND METHODS: We analyzed a total of 163 hepatic lymph nodes that were removed during surgery from 55 patients with synchronous liver metastasis of colorectal cancer, who underwent resection of primary tumor without any residual lesions except for liver metastasi (e) s. The relationship between the size and metastasis was examined on paraffin-embedded specimens. RESULTS: The maximal and minimal diameters were significantly greater in positive lymph nodes (n=35) than in negative lymph nodes (n=128). The area under the curve of receiver operating curve for predicting metastasis by size was 0.69. The sensitivity, specificity, and accuracy were 62.9%, 60.9%, and 61.4%, respectively, when the cutoff value was set at 7 mm. CONCLUSION: These findings suggest that selecting patients with hepatic lymph node metastasis based on the size of lymph nodes would be difficult.     

Atelocollagen-mediated local and systemic applications of myostatin-targeting siRNA increase skeletal muscle mass

RNA interference (RNAi) offers a novel therapeutic strategy based on the highly specific and efficient silencing of a target gene. Since it relies on small interfering RNAs (siRNAs), a major issue is the delivery of therapeutically active siRNAs into the target tissue/target cells in vivo. For safety reasons, strategies based on vector delivery may be of only limited clinical use. The more desirable approach is to directly apply active siRNAs in vivo. Here, we report the effectiveness of in vivo siRNA delivery into skeletal muscles of normal or diseased mice through nanoparticle formation of chemically unmodified siRNAs with atelocollagen (ATCOL). ATCOL-mediated local application of siRNA targeting myostatin, a negative regulator of skeletal muscle growth, in mouse skeletal muscles or intravenously, caused a marked increase in the muscle mass within a few weeks after application. These results imply that ATCOL-mediated application of siRNAs is a powerful tool for future therapeutic use for diseases including muscular atrophy.