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Recent molecular evidence of genetically distinct hantaviruses in shrews, captured in widely separated geographical regions, corroborates decades-old reports of hantavirus antigens in shrew tissues. Apart from challenging the conventional view that rodents are the principal reservoir hosts, the recently identified soricid-borne hantaviruses raise the possibility that other soricomorphs, notably talpids, similarly harbor hantaviruses. In analyzing RNA extracts from lung tissues of the Japanese shrew mole (Urotrichus talpoides), captured in Japan between February and April 2008, a hantavirus genome, designated Asama virus (ASAV), was detected by RT-PCR. Pairwise alignment and comparison of the S-, M-, and L-segment nucleotide and amino acid sequences indicated that ASAV was genetically more similar to hantaviruses harbored by shrews than by rodents. However, the predicted secondary structure of the ASAV nucleocapsid protein was similar to that of rodent- and shrew-borne hantaviruses, exhibiting the same coiled-coil helix at the amino terminus. Phylogenetic analyses, using the maximum-likelihood method and other algorithms, consistently placed ASAV with recently identified soricine shrew-borne hantaviruses, suggesting a possible host-switching event in the distant past. The discovery of a mole-borne hantavirus enlarges our concepts about the complex evolutionary history of hantaviruses.  相似文献   
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Background and Aims: A prospective , non‐randomized cohort study on long‐term lamivudine treatment , comparing efficacy, drug resistance, and prognosis for various stages of chronic hepatitis B virus (HBV)–related liver disease was performed to elucidate the significance and indication of lamivudine for individual patients at each stage of disease. Methods: A total of 158 cases consisting of 87 chronic hepatitis, 28 compensated cirrhosis, and 43 decompensated cirrhosis, with serum HBV‐DNA > 5 log10 copies/mL and with elevated alanine aminotransferase (ALT) over twice the upper normal limit or complications of hepatic insufficiency, were administered 100 mg of lamivudine daily and monitored for HBV markers, biochemistry, and prognosis. Results: Lamivudine reduced HBV‐DNA and ALT equally in all groups. Serum albumin, prothrombin time (%), and platelet count increased in all groups. The increased margin of albumin was the highest in the decompensated cirrhosis and higher in the compensated cirrhosis than the chronic hepatitis groups. Cumulative incidence of virologic breakthrough was 16%, 42%, 49%, and 53% at 12, 24, 36, and 48 months, respectively, and the strongest predictive factor for lamivudine resistance was persistent HBV‐DNA at 3 months. Ascites, encephalopathy, and jaundice improved in the majority of patients with decompensated cirrhosis. On the other hand, hepatic failure developed or deteriorated in 10 patients after virologic breakthrough, and nine of them had decompensated cirrhosis. Conclusions: Lamivudine was effective in reducing HBV‐DNA and improving hepatic reserve at all stages and was most beneficial and significant for decompensated cirrhosis. Meanwhile, close monitoring of viral load and immediate rescue treatment for lamivudine resistance is necessary to prevent hepatic failure in decompensated cirrhosis.  相似文献   
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Celiac disease is a systemic autoimmune disorder leading to manifestations of malabsorption syndrome. A 47-year-old Japanese man developed severe diarrhea after surgery for gastric cancer. The diarrhea persisted for seven months, leading to a state of malabsorption. Celiac disease was suspected based on small bowel capsule endoscopy findings. The duodenal findings observed during gastric cancer surgery were reassessed, and Marsh-Oberhuber classification type 3c celiac disease was diagnosed. The anti-tissue glutaminase antibody test results were positive. The patient was started on a gluten-free diet, following which the diarrhea resolved, and the nutritional status improved. Adjuvant therapy after gastric cancer surgery was initiated.  相似文献   
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Multiple hepatocellular carcinoma (HCC) is divided into two categories: intrahepatic metastasis (IM), which is a true relapse of HCC, and multicentric origin (MO), which is a second primary tumor. Clinical diagnosis of multiple HCC is usually made based on tumor location and/or time to recurrence; however, it is often difficult to distinguish the two types of multiple HCC. Using 41 matched pairs of multiple HCC specimens, we confirmed the accuracy of clinical diagnoses using exome sequence data and investigated the importance of discriminating the type of multiple HCC. Genomic analysis revealed that 18 (43.9%) patients diagnosed as having genomic IM had common mutations in a pair of HCC tumors with the main tumor of these patients being more progressive compared to those with genomic MO. The accuracy of clinical diagnosis based on lobe (Definition 1) and segment (Definition 2) were 68.3% and 78.0%, respectively. Intriguingly, recurrence ≥2 years after initial surgery for 3 patients was IM. The survival of patients with clinical IM was significantly shorter than for those with clinical MO based on both Definition 1 (P = 0.045) and Definition 2 (P = 0.043). However, mean survival was not different between the patients with genomic IM and those with MO (P = 0.364). Taken together, genomic analysis elucidated that liver cancer may spread more extensively and more slowly than previously thought. In addition, distinguishing multiple HCC as IM or MC may have provided biological information but was not of clinical importance with respect to patient prognosis.  相似文献   
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BackgroundLocal tumor recurrence of hepatocellular carcinoma (HCC) often occurs in blood drainage areas. Corona enhancement is determined by computed tomography during hepatic arteriography (CTHA) and is considered to represent the blood drainage area. This study aimed to investigate the relationship between embolization of corona enhancement area and local tumor recurrence of patients with HCC who underwent transcatheter arterial chemoembolization (TACE).Patients and methodsThe study retrospectively selected 53 patients with 60 HCC nodules that showed corona enhancement area on late-phase CTHA and showed homogenous accumulation of iodized oil throughout the nodule on non-contrast-enhanced CT performed immediately after TACE. We divided the nodules into two groups, according to whether the accumulation of iodized oil covered the entire corona enhancement area (group A) or not (group B). Local tumor recurrence was compared between the two groups.ResultsThe cumulative local tumor recurrence rates for group A (n = 36) were 2.8%, 2.8%, 8.3% at 3, 6, and 12 months, respectively, whereas the recurrence rates for group B (n = 24) were 20.8%, 45.8%, 75% at 3, 6, and 12 months, respectively. The cumulative local tumor recurrence rates for group A were significantly lower than those for group B (hazard ratio, 0.079; 95% confidence interval, 0.026–0.24; p < 0.001).ConclusionsThe results of the study suggest that the corona enhancement area may be an accurate safety margin in TACE which should be performed until the embolic area covers the entire corona enhancement area.Key words: corona enhancement, transcatheter arterial chemoembolization, computed tomography during hepatic arteriography, hepatocellular carcinoma  相似文献   
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Background and Aim:  Multipotential mesenchymal stem cells (MSC), present in many organs and tissues, represent an attractive tool for the establishment of a successful stem cell-based therapy in the field of regeneration medicine. Adipose tissue mesenchymal stem cells (AT-MSC), known as adipose-derived stem cells (ASC) are especially attractive in the context of future clinical applications because of their high accessibility and minimal invasiveness during the procedure to obtain them. The goal of the present study was to induce human ASC into functional hepatocytes in vitro within a very short period of time and to check their therapeutic potential in vivo .
Methods:  In vitro generated ASC-derived hepatocytes were checked for hepatocyte-specific markers and functions. Afterwards, they were transplanted into nude mice with liver injury. Twenty-four hours after transplantation, biochemical parameters were evaluated in blood serum.
Results:  We have shown here that ASC can be differentiated into hepatocytes within 13 days and can reach the functional properties of primary human hepatocytes. After transplantation into mice with acute liver failure, ASC-derived hepatocytes can restore such liver functions as ammonia and purine metabolism. Markers of liver injury, alanine aminotransferase, aspartate aminotransferase, as well as ammonia, were decreased after ASC-derived hepatocyte transplantation.
Conclusions:  Our data highlight the properties of ASC as having a special affinity for hepatocyte differentiation in vitro and liver regeneration in vivo . Thus, ASC may be a superior choice for the establishment of a therapy for injured liver.  相似文献   
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It is well known that Fas ligand and anti-Fas antibodies can induce apoptosis, although some cancer cells are resistant to their stimuli. On the other hand, phosphatidylinositol 3-kinase (PI3 K) and Akt mediate the survival signal and allow the cells to escape from apoptosis in various human cancers. Thus, we postulated that LY294002, a PI3 K inhibitor, should inactivate Akt, consequently inhibiting cell proliferation and increase apoptosis in the human gastric carcinoma cell line, MKN-45. Previously, we reported that MKN-45 was resistant against the anti-Fas antibody, CH-11, without interferon-gamma pretreatment in vitro. LY294002 caused a decrease of phosphorylated-Akt and an inhibition of cell proliferation via cell cycle arrest in the G0/G1 phase by P27/Kip1 accumulation, but there was no obvious induction of apoptosis. The simultaneous treatment of LY294002 and CH-11 significantly induced apoptosis confirmed by morphology and DNA ladder formation. Decreased phosphorylated-Akt by LY294002 treatment led to a down-regulation of Mcl-2 and phosphorylated Bad proteins, which are anti-apoptotic factors and belong to the Bcl-2 family. On the other hand, expression levels of the other anti-apoptotic factors, such as FLICE-inhibitory protein (FLIP), Bcl-2 and Bcl-XL, which are associated with the Fas-mediated apoptotic signal pathway, did not change after LY294002 treatment. We concluded that: 1) the PI3K-Akt pathway plays an important role in preventing Fas-mediated apoptosis; and 2) a PI3 K inhibitor, such as LY294002, might be a useful anti-tumoral agent for gastric carcinoma.  相似文献   
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