Expression profiles of genes associated with viral entry in HCV-infected human liver

Recent studies have demonstrated that several cellular factors are involved in entry of hepatitis C virus (HCV) into host cells. Detailed gene expression profiles of these factors in HCV-infected livers have not been reported for humans. Transcriptional levels of LDL receptor (LDLR), CD81, scavenger receptor class B type I (SR-BI), claudin-1, and occludin genes in liver samples from patients with chronic hepatitis C were investigated. Serum levels of LDL-cholesterol (LDL-C) and HCV core antigen were also evaluated, and expression of claudin-1 and occludin were immunohistochemically analyzed. Compared with normal liver, transcription of LDLR and claudin-1 genes was significantly suppressed (P < 0.0001) and occludin transcription was significantly up-regulated in HCV-infected livers (P < 0.0001). Significant positive correlations were found for LDLR versus occludin, LDLR versus claudin-1, occludin versus claudin-1, and CD81 versus SR-BI in HCV-infected (P = 0.0012, P < 0.0001, P = 0.0004, and P < 0.0001, respectively) and normal livers (P < 0.0001, P = 0.0051, P < 0.0001, and P < 0.0001, respectively). Positive correlation was observed between serum levels of HCV core antigen and LDL-C (P = 0.0147), with their levels negatively correlated to LDLR (P = 0.0270 and P = 0.0021, respectively). Immunohistochemically, hepatocellular expression of claudin-1 and occludin was increased in HCV-infected livers. Different levels of expression were demonstrated at the mRNA and protein levels for occludin and claudin-1 in HCV-infected and normal livers. Correlation of elements associated with viral entry was comparable in HCV-infected and normal livers.

Two cyanobacterial strains can be distinguished from each other and other eukaryotic algae by spectral absorption method

Spectral absorption method based on two step linear regression analyses (TSLR) was applied for detection of two strains of cyanobacterium, Microcystis (blue-green algae) from eukaryotic algae. Both blue-green algae, algae and dissolved organic carbon (DOC) were considered from freshwater bodies in Kanto region, Japan. The results show that blue-green species can be detected from other algal species using absorption spectra of water samples. In this study statistical analysis was done by TSLR method, which determined the gradient vectors of single algal species and DOC. We believe that this method might be useful in environmental monitoring of freshwater algae.

Menopausal status influences the relationship between serum ghrelin levels and fat mass in healthy women

OBJECTIVE

To examine the relationships of fasting serum ghrelin levels to bone mass index (BMI) and body fat mass, focusing on the effects of menopausal status and changes in fat distribution in women after menopause.

DESIGN

An observational study.

PATIENTS

Fifty-nine pre-menopausal and 31 post-menopausal healthy Japanese women volunteers were enrolled in the present study.

MEASUREMENTS

Total and regional body fat mass weight was measured by dual energy x-ray absorptiometry. Serum ghrelin was measured. Relationships of serum ghrelin levels to weight, BMI, total body and regional fat mass weight were separately examined in post-menopausal and pre-menopausal women.

RESULTS

Serum ghrelin levels were significantly inversely correlated with weight (r = -0.377, p < 0.05, Pearson's correlation test), right arm fat mass (r = -0.408, p < 0.05), left arm fat mass (r = -0.386, p < 0.05), trunk fat mass (r = -0.361, p < 0.05) and total body fat mass (r = -0.383, p < 0.05) in the post-menopausal women but not in pre-menopausal women.

CONCLUSIONS

Menopausal status may influence the relationship between serum ghrelin levels and fat mass in healthy women.

Improvement of scopolamine-induced memory impairment by Z-ajoene in the water maze in mice

Z-ajoene, a major compound containing sulfur in oil-macerated garlic products, exhibited inhibitory effects against scopolamine-induced memory impairment in mice using the Morris water maze test. The effects of Z-ajoene were observed dose-dependently (0.25-25 mg/kg). At the highest dosage, the memory performance of mice was improved compared to normal mice. The acetylcholinesterase (AChE) activity in the brain was reduced by administration of Z-ajoene dose-dependently. However, alliin and diallyl disulfide, organosulfur compounds from garlic, did not improve memory performance nor AChE inhibitory effect. These results suggest that Z-ajoene may act on the cholinergic system and on memory impairment caused by excess activity of AChE.

The leptin receptor in human osteoblasts and the direct effect of leptin on bone metabolism

It is important to elucidate whether the leptin receptor, especially the long signal-transducing form of the leptin receptor (OB-Rb) is expressed in human osteoblasts. We detected the expression of human OB-Rb in cultured commercially available human osteoblasts (NHOst cells) using real-time quantitative reverse transcriptase polymerase chain reaction (RT-PCR). After confirming the expression of OB-Rb, we investigated the effect of leptin on NHOst cells. Leptin enhanced cell proliferation of the cells shown by the MTT assay. Furthermore, leptin changed the copy numbers of Bax and Bcl-2 mRNAs in the cultured cells as shown by real-time quantitative RT-PCR, although the effect was not consistent. Leptin did not change the production of osteocalcin and osteopontin by the cells. Leptin did not change the expression of OB-Rb mRNA in the cells. In conclusion, OB-Rb mRNA is expressed in cultured commercially available human osteoblasts. Leptin may have some effects on bone metabolism by directly modulating cell proliferation and apoptosis of osteoblasts in humans.

Bone mineral density of the lumbar spine is associated with TNF gene polymorphisms in early postmenopausal Japanese women

We investigated the relationships between tumor necrosis factor (TNF) gene polymorphism, circulating TNF-alpha (TNF-alpha) concentrations, and bone mineral density (BMD) in the lumbar spine. TNF gene polymorphisms studied were the Nco I polymorphism within the first intron of TNF-beta (TNF-beta) and three single nucleotide polymorphisms in the promoter region of the TNF-alpha gene, at positions -857, -863, and -1031. Allelic variants of the TNF gene were identified using restriction fragment length polymorphism (RFLP) analysis in 177 postmenopausal Japanese women within 10 years after menopause, aged 56.4 +/- 4.5 years (mean +/- SD). A significantly higher prevalence of the alleles TNF-alpha-863A (20.3% versus 9.9%) and TNF-alpha-1031C (21.3% versus 12.4%) was seen in the low BMD group (Z-score < 0, n = 91) than in the high BMD group (0 < Z-score, n = 86). In genotype analysis, although difference did not reach a significant level, women with the rarest allelic variants, i.e., homozygous TNFbl, TNF-alpha-863A, and TNF-alpha-1031C, showed the lowest BMD Z-scores. Women with another rarest allelic variant, TNF-alpha-857T/T had significantly lower BMD Z-scores than did women with TNF-alpha-857C/T or -857C/C. The BMD Z-score decreased significantly with an increase in the total number of such rare alleles. Serum concentrations of TNF-alpha did not differ significantly among groups divided by genotypes. Multiple linear regression analysis revealed that the total number of rare alleles, in addition to the body mass index and the number of years since menopause, was an independent predictor of the BMD. These presumptive functional polymorphisms of the TNF gene may be associated with the lumbar spine BMD in early postmenopausal Japanese women.

A gene for a Class II DNA photolyase from Oryza sativa: cloning of the cDNA by dilution-amplification

Ultraviolet radiation induces the formation of two classes of photoproducts in DNA-the cyclobutane pyrimidine dimer (CPD) and the pyrimidine [6-4] pyrimidone photoproduct (6-4 product). Many organisms produce enzymes, termed photolyases, which specifically bind to these lesions and split them via a UV-A/blue light-dependent mechanism, thereby reversing the damage. These photolyases are specific for either CPDs or 6-4 products. Two classes of photolyases (class I and class II) repair CPDs. A gene that encodes a protein with class II CPD photolyase activity in vitro has been cloned from several plants including Arabidopsis thaliana, Cucumis sativus and Chlamydomonas reinhardtii. We report here the isolation of a homolog of this gene from rice (Oryza sativa), which was cloned on the basis of sequence similarity and PCR-based dilution-amplification. The cDNA comprises a very GC-rich (75%) 5; region, while the 3; portion has a GC content of 50%. This gene encodes a protein with CPD photolyase activity when expressed in E. coli. The CPD photolyase gene encodes at least two types of mRNA, formed by alternative splicing of exon 5. One of the mRNAs encodes an ORF for 506 amino acid residues, while the other is predicted to code for 364 amino acid residues. The two RNAs occur in about equal amounts in O. sativa cells.

Tegumentary papillae of Echinostoma caproni cercariae (Trematoda: Echinostomatidae)

Argentophilic staining and scanning electron microscopy were used to study the tegumentary papillae of Echinostoma caproni cercariae. The most abundant tegumentary papillae were uniciliate, but multiciliate papillae were also found, mainly on the ventral aspect of the oral collar. The distribution pattern of the papillae on the body and tail was in general similar to that seen in the cercariae of other 37-collar-spined Echinostoma species. Some differences were noted between E. caproni and the allopatric species, E. trivolvis. E. caproni has a greater number of papillae associated with the collar spines than does E. trivolvis. E. caproni has uniciliate papillae on the acetabulum, whereas E. trivolvis does not. Chaetotaxy is useful to distinguish subtle morphological differences in cercarial species in the 37-collar-spined Echinostoma complex.

Hyperosmotic stimuli induces recruitment of aquaporin-1 to plasma membrane in cultured rat peritoneal mesothelial cells

Aquaporin-1 (AQP-1) has been reported to play an important role in peritoneal dialysis. To determine the precise mechanism involved, we used cultured rat peritoneal mesothelial cells (RPMCs) to examine the translocation of AQP-1 to the plasma membrane induced by hyperosmotic stimuli. Cultured RPMCs obtained from male Sprague-Dawley rats were incubated at room temperature in Dulbecco modified Eagle medium/F12 (DMEM/F12) with and without glucose or mannitol as the hyperosmotic stimulus. The plasma membrane was then extracted by the Percoll gradient method. Finally, the abundance AQP-1 molecules in the membrane fraction was determined by Western blot analysis. Significant enhancement of AQP-1 abundance (p < 0.05) was observed within 2.5 minutes of the addition of 5% glucose to the medium. The increase was sustained in its abundance through 15 minutes. Abundance of AQP-1 was also increased (p < 0.05) by the addition of 5% mannitol. These results suggest that hyperosmotic stimuli could generate increased AQP-1 abundance in the plasma membrane by translocation of AQP-1 protein from recycling endosomes or early endosomes to the plasma membrane, rather than by protein synthesis via newly expressed mRNA. The latter mechanism would be expected to take more time.

Serum levels of vascular endothelial growth factor and cavity formation in active pulmonary tuberculosis

BACKGROUND

In active pulmonary tuberculosis, certain cytokines have been postulated to be related to cavity formation, although the detailed mechanism of cavity formation is not yet known.

OBJECTIVE

We examined the relationship between cavity formation in pulmonary tuberculosis and vascular endothelial growth factor (VEGF), which functions as an angiogenesis factor.

METHODS

Forty-eight patients with active pulmonary tuberculosis were divided into two groups according to cavity formation as evaluated by chest high-resolution computed tomography. We evaluated serum VEGF levels by enzyme immunoassay.

RESULTS

Group A (with cavities) was comprised of 22 patients and group B (without cavities) was comprised of 26 patients. The serum levels of VEGF were significantly higher in group B (58.733 +/- 21.612 pg/ml) than those in normal individuals (8.739 +/- 3.656 pg/ml) and in group A (13.053 +/- 8.670 pg/ml) (Mann-Whitney U test, p = 0.0149 and p = 0.0481, respectively). Serum levels of interleukin-8 and tumor necrosis factor-alpha were not significantly different between the two groups.

CONCLUSION

These findings suggested that increased serum VEGF levels subdue cavity formation in active pulmonary tuberculosis.

Molecular heterogeneity of heat-stable toxin-producing and non-producing Escherichia coli O25 strains isolated in Japan

Escherichia coli O25 strains that produce heat-stable toxin (ST) have been recently isolated in Japan, and epidemiological study of this type of enterotoxigenic E. coli is required. In this study the heterogeneity of 16 ST-producing and non-producing strains of E. coli O25 was investigated. All eight ST-producing strains were shown to have STIb gene, and seven of them had similar profiles of plasmids, ladder-banding of LPS in SDS-polyacrylamide gel electrophoresis, and chromosomal DNA digestions in pulsed-field gel electrophoresis (PFGE). In contrast, ST-non-producing strains were more heterogeneous in all parameters examined. PFGE of the digested chromosomal DNA with several restriction enzymes was proved to be an effective procedure to compare the closely related strains of E. coli O25.

Subthreshold stimulation in three types of reentrant supraventricular tachycardia: correlation with the results of catheter ablation

The effects of subthreshold stimulation (STS) by direct current were investigated in 20 patients with atrioventricular nodal reentrant tachycardia (AVNRT), 27 with atrioventricular reentrant tachycardia (AVRT) and 3 with idiopathic atrial reentrant tachycardia (IART) STS was delivered to each eligible site for ablation prior to radiofrequency application. STS was defined as 'positive' if it could terminate the tachycardia or disrupt the conduction of accessory pathways without myocardial capture and defined as 'negative' if it could not. Radiofrequency ablation was performed irrespective of a positive or negative result from STS and was successful in all 50 patients. Among the 50 successful ablation sites, STS was positive at 26 sites (11 sites in AVNRT, 12 in AVRT and 3 in IART). STS was positive at 4 sites where ablation failed in 3 patients with AVRT and was negative at 8 sites where ablation was successful in 4 patients with AVNRT and 4 with AVRT. The positive and negative predictive value of STS for the detection of the optimal ablation site were, respectively, 100% and 74% in AVNRT, 73% and 72% in AVRT, and both 100% in IART STS-guided mapping is a specific method to predict the successful catheter ablation of reentrant supraventricular tachycardia.

Protective effect of ajoene on acetaminophen-induced hepatic injury in mice

Ajoene, a garlic-derived sulfur-containing compound, exhibited a hepatoprotective effect against acetaminophen-induced liver injury in mice. A pretreatment with ajoene suppressed the rise in serum glutamic-pyruvic transaminase activity and the reduction in the hepatic reduced glutathione level. These effects of ajoene were observed dose-dependently (20-100 mg/kg). The pretreatment by ajoene also suppressed the decrease in hepatic protein thiol content resulting from acetaminophen administration.

Histopathological prognostic factors of adult granulosa cell tumors of the ovary

BACKGROUND

The prognostic factors of adult granulosa cell tumor (AGCT) have not been well defined.

METHODS

In 27 AGCT patients, we examined clinical stage, microscopic patterns, mitotic index (MI), and lymph-vascular space invasion (LVSI) to determine whether these factors were related to disease-free survival (DFS) of patients with AGCT. We also performed immunohistochemical examination for p53.

RESULTS

Seventeen cases represented stage I tumors, four stage II, five stage III, and one stage IV. Patients with stage I disease had more favorable prognosis than those with stage II to IV disease (p=0.034). There was no relation between the microscopic patterns and the DFS. The MI, which was categorized into < or =3/10 high power field (HPF) and > or =4/10 HPF, was significantly related to patients DFS (p<0.0005). The DFS time for patients with moderate or prominent LVSI was significantly shorter than that for patients with no or minimal LVSI (p<0.0001). By multivariate analysis, MI and LVSI were shown to be independent prognostic factors. Five of seven patients with recurrent tumor had extrapelvic spread; two in the abdominal cavity and three in the liver.

CONCLUSION

The results of this study suggest that prognosis for patients with AGCT depends on the MI and LVSI. During the follow-up period of patients, they need to be examined for distant metastasis including liver.

Genomic organization and transcription units of the human acyl-CoA synthetase 3 gene

Acyl-CoA synthetases (ACSs) play an essential role in fatty acid metabolism. ACS3 is an arachidonate-preferring enzyme expressed in a wide range of human tissues including brain, heart, placenta, prostate, skeletal muscle, testis and thymus. As an initial step to understanding the transcriptional regulation of the human ACS3 gene, we analyzed the genomic organization and transcription units of the human ACS3 gene. Sequence analysis of genomic clones demonstrates that the human ACS3 gene spans at least 80.6 kb and contains 17 exons. The human ACS3 gene was mapped between the sequence-tagged site markers D2S360 and WI-21901. Sequence inspection of the 5'-flanking region revealed potential DNA elements including CCAAT, AP-1, Oct-1, GATAs, SRY, CdxA, Nkx-2.5, c-Myb, HSF2, NF-AT, AP-2, NF-Y, and p300. A minimal promoter region required for the expression of the human ACS3 gene in melanoma G361 cells was determined.

Roles of prostaglandin I(2) and thromboxane A(2) in cardiac ischemia-reperfusion injury: a study using mice lacking their respective receptors

BACKGROUND

Prostaglandin (PG) I(2) and thromboxane (TX) A(2), the most common prostanoids in the cardiovascular system, are produced abundantly during cardiac ischemia/reperfusion (I/R); their roles in I/R injury, however, remain undetermined. We intended to clarify these roles of PGI(2) and TXA(2) using mice lacking the PGI(2) receptor, IP(-/-) mice, or the TXA(2) receptor, TP(-/-) mice.

METHODS AND RESULTS

The left anterior descending coronary artery was occluded for 1 hour and then reperfused for 24 hours. The size of myocardial infarct in IP(-/-) mice was significantly larger than that in wild-type mice, although the size of the area at risk was similar between the 2 groups of mice. In contrast, there was no such difference between TP(-/-) and wild-type mice. To further determine whether PGI(2) and TXA(2) act directly on the cardiac tissue or indirectly through their action on blood constituents, we perfused excised heart according to the Langendorff technique. The isolated heart was then subjected to global ischemia followed by reperfusion. In IP(-/-) mice, developed tension and coronary flow rate during reperfusion were significantly lower and release of creatine kinase was significantly higher than those in wild-type mice. There were no such differences, however, between TP(-/-) and wild-type mice.

CONCLUSIONS

PGI(2), which was produced endogenously during cardiac I/R, exerts a protective effect on cardiomyocytes independent of its effects on platelets and neutrophils. In contrast, TXA(2) has little role in the cardiac I/R injury.