Capillary-driven horseshoe vortex forming around a micro-pillar

HYPOTHESIS

Horseshoe vortices are known to emerge around large-scale obstacles, such as bridge pillars, due to an inertia-driven adverse pressure gradient forming on the upstream-side of the obstacle. We contend that a similar flow structure can arise in thin-film Stokes flow around micro-obstacles, such as used in textured surfaces to improve wettability. This could be exploited to enhance mixing in microfluidic devices, typically limited to creeping-flow regimes.

EXPERIMENTS

Numerical simulations based on the Navier-Stokes equations are carried out to elucidate the flow structure associated with the wetting dynamics of a liquid film spreading around a 50 μm diameter micro-pillar. The employed multiphase solver, which is based on the volume of fluid method, accurately reproduces the wetting dynamics observed in current and previous (Mu et al., Langmuir, 2019) experiments.

FINDINGS

The flow structure within the liquid meniscus forming at the foot of the micro-pillar evinces a horseshoe vortex wrapping around the obstacle, notwithstanding that the Reynolds number in our system is extremely low. Here, the adverse pressure gradient driving flow reversal near the bounding wall is caused by capillarity instead of inertia. The horseshoe vortex is entangled with other vortical structures, leading to an intricate flow system with high-potential mixing capabilities.

An automated rapid detection system using the quenching probe method for detecting interleukin 28B and inosine triphosphatase single nucleotide polymorphisms in chronic hepatitis C

Single nucleotide polymorphisms (SNPs) in the interleukin 28B gene (IL28B) are good pretreatment predictors of anti-hepatitis C virus (HCV) therapy with interferon. SNPs of the inosine triphosphatase (ITPA) gene are associated with reduced haemoglobin levels during treatment with ribavirin. The i-densy™ (Arkray, Inc.), which is based on the quenching probe (QP) method, automatically detects target genes in blood samples by fluorescence quenching within 100 min. Using a QP and primer set, a gene amplification response is generated that can quickly and easily detect a specific gene's arrangement by fluorometry. The present study was conducted to compare the utility of i-densy (QP method) with that of conventional direct sequencing (DS) for detecting SNPs in the IL28B and ITPA genes in chronic hepatitis C patients. Between June 2011 and January 2012, 73 consecutive patients underwent genotyping of IL28B, and 54 patients underwent genotyping of ITPA. All of the patients were seropositive for HCV-RNA. The IL28B and ITPA genotypes were tested for bi-allelic polymorphisms in rs8099917 (T/T, T/G and G/G; minor allele, G) and rs1127354 (C/C, C/A and A/A; minor allele, A), respectively. The results obtained with the QP method were identical to those obtained with the conventional DS method. The frequency of the IL28B genotypes TT, GT and GG were 74%, 24.7% and 1.4%, respectively, and those of the ITPA genotypes CC, AC and AA were 68.5%, 29.6% and 1.9%, respectively. These results indicate that the i-densy using the QP method can automatically, quickly and easily identify genotypes of IL28B and ITPA.

Gasless laparoscopically assisted myomectomy using a wound retraction system

INTRODUCTION

The purpose of this study was to elucidate the feasibility of gasless laparoscopically assisted myomectomy (LAM) using a wound retraction system. This method treats symptomatic uterine myomas by combining laparoscopy with a mini-laparotomy to enucleate myoma nodules and to close the uterine myometrium.

METHODS

This study includes 275 patients who underwent gasless LAM. For patients with fewer than three myoma nodules, the location of the largest nodule was classified as anterior, fundal, or posterior. The operative outcomes, intraoperative and postoperative courses, and complications were examined.

RESULTS

All operations were performed satisfactorily, and no conversions to laparotomy were required. None of the patients developed serious complications. The mean blood loss and operating time were 190.3 mL and 152.2 minutes, respectively. The mean myoma size was 8.9 cm, and the mean number of myomas per patient was 2.8. The average postoperative hospital stay was 5.7 days. There were no significant differences in resected myoma size, blood loss, and surgical duration with respect to the location of the largest nodule.

CONCLUSION

Gasless LAM with a wound retractor is feasible and allows surgeons to perform myomectomy safely and cost-effectively, without requiring advanced laparoscopic surgical skills and while maintaining minimum invasiveness.

Amyloidogenic and non-amyloidogenic transthyretin Asn 90 variants

Recently, a new transthyretin (TTR) variant was described in the normal Portuguese and German populations. The same substitution was found associated with familial amyloidotic polyneuropathy (FAP) in an American family of Italian origin. Comparative isoelectric focusing studies showed a difference in the mobility pattern between the non-pathogenic and pathogenic variants. However, comparative DNA sequencing between them did not reveal any additional mutation. Comparative isoelectric focusing between the variants and TTR Asn 90 produced by recombinant techniques indicated that the non-pathogenic variant has the electrophoretic behaviour expected for the mutation. We suggest that an as yet unknown post-translational modification may have occurred in the FAP-associated Asn 90 variant, turning it into an amyloidogenic molecule.

Serial histologic observation of endometrial adenocarcinoma treated with high-dose progestin until complete disappearance of carcinomatous foci--review of more than 25 biopsies from five patients

This study aimed to document chronologic histologic changes of endometrial biopsies from patients with endometrial adenocarcinoma on high-dose progestin therapy. Seven patients with presumptive FIGO stage IA endometrial adenocarcinoma treated with medroxyprogesterone acetate 600 mg/day were investigated retrospectively. Good response was defined as complete disappearance of carcinoma foci within 16 weeks of treatment and poor response as the presence of residual foci at 16 weeks. Two patients were poor responders and were excluded from the study, while five good responders were analyzed. Hematoxylin and eosin (H&E)-stained slides were reviewed and analyzed based on nine histologic features to describe the histology observed commonly in good responders. All the five good responders showed relatively uniform morphologic changes during the high-dose progestin therapy and the common histology was described as follows. The first change was swelling of the neoplastic glandular epithelial cells with pale vacuolated cytoplasm and round to oval nuclei. Mitotic arrest was also observed. Next, the epithelia were disrupted by lymphoplasmocytic infiltration and replaced by low cuboidal epithelium with or without squamous or morular metaplasia. The stromal area increased with predecidual changes. The final morphology was small atrophic glands scattered in predecidual stroma with dilated vessels. Therefore, the morphologic change of the endometrial biopsy observed in earlier stage of treatment might be able to predict good response to high-dose progestin therapy.

Genetic variations and haplotype structures of the ABCB1 gene in a Japanese population: an expanded haplotype block covering the distal promoter region, and associated ethnic differences

As functional ABCB1 haplotypes were recently reported in the promoter region of the gene, we resequenced the ABCB1 distal promoter region, along with other regions (the enhancer and proximal promoter regions, and all 28 exons), in a total of 533 Japanese subjects. Linkage disequilibrium (LD) analysis based on 92 genetic variations revealed 4 LD blocks with the same make up as previously described (Blocks -1, 1, 2 and 3), except that Block 1 was expanded to include the distal promoter region, and that a new linkage between polymorphisms -1,789G>A in the distal promoter region and IVS5 + 123A>G in intron 5 was identified. We re-assigned Block 1 haplotypes, and added novel haplotypes to the other 3 blocks. The reported promoter haplotypes were further classified into several types according to tagging variations within Block 1 coding or intronic regions. Our current data reconfirm the haplotype profiles of the other three blocks, add more detailed information on functionally-important haplotypes in Block 1 and 2 in the Japanese population, and identified differences in haplotype profiles between ethnic groups. Our updated analysis of ABCB1 haplotype blocks will assist pharmacogenetic and disease-association studies carried out using Asian subjects.

Haplotype structures of the UGT1A gene complex in a Japanese population

Genetic polymorphisms of UDP-glucuronosyltransferases (UGTs) are involved in individual and ethnic differences in drug metabolism. To reveal co-occurrence of the UGT1A polymorphisms, we first analyzed haplotype structures of the entire UGT1A gene complex using the polymorphisms from 196 Japanese subjects. Based on strong linkage disequilibrium between UGT1A8 and 1A10, among 1A9, 1A7, and 1A6, and between 1A3 and 1A1, the complex was divided into five blocks, Block 8/10, Block 9/6, Block 4, Block 3/1, and Block C, and the haplotypes for each block were subsequently determined/inferred. Second, using pyrosequencing or direct sequencing, additional 105 subjects were genotyped for 41 functionally tagged polymorphisms. The data from 301 subjects confirmed the robustness of block partitioning, but several linkages among the haplotypes with functional changes were found across the blocks. Thus, important haplotypes and their linkages were identified among the UGT1A gene blocks (and segments), which should be considered in pharmacogenetic studies.

Gene fusion involving HMGIC is a frequent aberration in uterine leiomyomas

HMGIC, a high-mobility-group protein gene encoding an architectural transcription factor, was recently identified as the target of gene fusion in a variety of human benign mesenchymal tumors; some of these events were chromosomal translocations involving 12q13-15. HMGIC consists of three DNA-binding domains (encoded by exons 1-3), a spacer, and an acidic carboxyl-terminal regulatory domain (exons 4-5). To determine the spectrum and nature of the aberrations in uterine myomas in Japanese patients, we systematically examined the tumors of 45 patients for all possible types of gene fusions involving HMGIC, by means of 3'-rapid amplification of cDNA ends (RACE) and reverse transcriptase-polymerase chain reaction (RT-PCR) experiments. HMGIC gene fusions were found in 16 (36%) of the tumors; aberrant splicings to five cryptic sequences located in introns of the HMGIC gene were found in 11 of these cases, and translocations causing juxtaposition to other genes, such as COX6C and RA D51B, were found in 5. In all fusion transcripts, the first two or three exons of HMGIC were fused to ectopic sequences. Our results suggest that a fusion event, resulting in the separation of the DNA-binding domains of HMGIC from the spacer and the acidic carboxyl-terminal regulatory domain, is a common tumorigenic mechanism in the development of uterine myomas.

Comparison of the essential oils of Glehnia littoralis from Northern and Southern Japan

The essential oils from aerial and root parts of Glehnia littoralis were investigated by GC and GC-MS, and 125 compounds were identified. Plants were obtained from Northern and Southern Japan, and samples from the same locations were cultivated either exposed or unexposed to sunlight. The main constituents of the essential oils were found to be alpha-pinene (0.03-13.40%), limonene (0.15-10.71%), beta-phellandrene (0.03-22.93%), germacrene B (0.27-8.33%), spathulenol (0.24-6.50%), beta-oplopenone (0.06-6.47%), panaxynol (0.38-24.58%), propyl octanoate (3.44-27.85%), hexadecanoic acid (0.45-27.80%), and linoleic acid (0.16-17.56%). Terpenoid compounds were found in higher concentrations in the Northern type oils than in the Southern types, whereas the concentration of polyacetylenic compounds was higher in one of the Southern samples, except from the aerial parts of those cultivated exposed. Consequently, the constitution of the essential oils from G. littoralis could be separated into Northern and Southern types.

Genetic model of multi-step breast carcinogenesis involving the epithelium and stroma: clues to tumour-microenvironment interactions

Although numerous studies have reported that high frequencies of loss of heterozygosity (LOH) at various chromosomal arms have been identified in breast cancer, differential LOH in the neoplastic epithelial and surrounding stromal compartments has not been well examined. Using laser capture microdissection, which enables separation of neoplastic epithelium from surrounding stroma, we microdissected each compartment of 41 sporadic invasive adenocarcinomas of the breast. Frequent LOH was identified in both neoplastic epithelial and/or stromal compartments, ranging from 25 to 69% in the neoplastic epithelial cells, and from 17 to 61% in the surrounding stromal cells, respectively. The great majority of markers showed a higher frequency of LOH in the neoplastic epithelial compartment than in the stroma, suggesting that LOH in neoplastic epithelial cells might precede LOH in surrounding stromal cells. Furthermore, we sought to examine pair-wise associations of particular genetic alterations in either epithelial or stromal compartments. Seventeen pairs of markers showed statistically significant associations. We also propose a genetic model of multi-step carcinogenesis for the breast involving the epithelial and stromal compartments and note that genetic alterations occur in the epithelial compartments as the earlier steps followed by LOH in the stromal compartments. Our study strongly suggests that interactions between breast epithelial and stromal compartments might play a critical role in breast carcinogenesis and several genetic alterations in both epithelial and stromal compartments are required for breast tumour growth and progression.

Opposite association of two PPARG variants with cancer: overrepresentation of H449H in endometrial carcinoma cases and underrepresentation of P12A in renal cell carcinoma cases

Peroxisome proliferator activated receptor gamma (PPARgamma) is a nuclear hormone receptor that has been shown to regulate differentiation and cell growth. Studies of the differentiative effects of PPARgamma agonists on several cancer cell lines led to the hypothesis that dysfunction of PPARgamma contributes to tumorigenesis. These functional observations were strengthened by genetic evidence: somatic loss-of-function mutations in PPARG, encoding PPARgamma, in sporadic colorectal carcinomas and somatic translocation of PAX8 and PPARG in follicular thyroid carcinoma. Recently overrepresentation of the H449H variant was found in a cohort of American patients with glioblastoma multiforme. The glioblastoma multiforme data suggest that PPARG contributes common, low-penetrance alleles for cancer susceptibility. To test this hypothesis in a broader range of cancers we examined a series of carcinomas of the cervix, endometrium, ovary, prostate, and kidney for germline sequence variation in PPARG. In addition to the two common sequence variants, P12A and H449H, there were five other sequence variants. P12A alleles were underrepresented in renal cell carcinoma patients compared to country-of-origin race-matched controls (3.75% vs. 12.1%, P<0.04). In contrast, the H449H variant was overrepresented in individuals with endometrial carcinoma compared to controls (14.4% vs. 6.25%, P<0.02). These observations lend genetic evidence consistent with our hypothesis that PPARG serves as a common, low-penetrance susceptibility gene for cancers of several types, especially those epidemiologically associated with obesity and fat intake.

Is arterial surgery advisable for patients over 80 years of age?

BACKGROUND

Recently life expectancy has become longer and longer. The purpose of this study was to analyse whether arterial surgery for patients over 80 years of age is advisable.

METHODS

During the last 14 years, 527 patients, 50 of whom were over 80 and 477 of whom were under 80 years of age, received graft replacement or bypass surgery. They suffered from ruptured abdominal aortic aneurysm (R-AAA, n=21), non-ruptured abdominal aortic aneurysm (N-R AAA, n=133) or arteriosclerosis obliterans (ASO, n=373). Complications such as cerebrovascular disease, ischemic heart disease, respiratory and kidney dysfunction, and risk factors for ASO were also checked.

RESULTS

All of the patients over 80 with R-AAA (n=3/3) and 50% of the patients under 80 with R-AAA (n=9/18) died during their stay in the hospital. However, none of the N-R AAA patients over 80 (n=0/7) and only one of the 126 N-R AAA patients (0.8%) under 80 died. For the patients over 80 with ASO, the graft patency rate was better than the patients survival rate. There were no age-specific factors that should condemn arterial surgery for patients over 80 years of age.

CONCLUSIONS

Arterial surgery should not be ruled out on the basis of age alone.

Frequent loss of PTEN expression is linked to elevated phosphorylated Akt levels, but not associated with p27 and cyclin D1 expression, in primary epithelial ovarian carcinomas

PTEN (MMAC1/TEP1), a tumor suppressor gene on chromosome subband 10q23.3, is variably mutated and/or deleted in a variety of human cancers. Germline mutations in PTEN, which encode a dual-specificity phosphatase, have been implicated in at least two hamartoma tumor syndromes that exhibit some clinical overlap, Cowden syndrome and Bannayan-Riley-Ruvalcaba syndrome. Among several series of ovarian cancers, the frequency of loss of heterozygosity (LOH) of markers flanking and within PTEN, is approximately 30 to 50%, and the somatic intragenic PTEN mutation frequency is <10%. In this study, we screened primary adenocarcinomas of the ovary for LOH of polymorphic markers within and flanking the PTEN gene and for intragenic mutations of the PTEN gene and compared them to PTEN expression using immunohistochemistry. Furthermore, we sought to detect the expression of the presumed downstream targets of PTEN, such as P-Akt, p27, and cyclin D1 by immunohistochemistry. LOH at 10q23 was observed in 29 of 64 (45%) cases. Of the 117 samples, 6 somatic intragenic PTEN mutations, 1 germline mutation, and 1 novel polymorphism were found in 7 (6%) patients. Immunostaining of 49 ovarian cancer samples revealed that 13 (27%) were PTEN immunostain-negative, 25 (51%) had reduced staining, and the rest (22%) were PTEN expression-positive. Among the 44 informative tumors assessed for 10q23 LOH and PTEN immunostaining, there was an association between 10q23 LOH and decreased or absent staining (P = 0.0317). Of note, there were five (11%) tumors with neither mutation nor deletion that exhibited no PTEN expression and 10 (25%) others without mutation or deletion but had decreased PTEN expression. Among the 49 tumors available for immunohistochemistry, 28 (57%) showed P-Akt-positive staining, 24 (49%) had decreased p27 staining, and cyclin D1 was overexpressed in 35 (79%) cases. In general, P-Akt expression was inversely correlated with PTEN expression (P = 0.0083). These data suggest that disruption of PTEN by several mechanisms, allelic loss, intragenic mutation, or epigenetic silencing, all contribute to epithelial ovarian carcinogenesis, and that epigenetic silencing is a significant mechanism. The Akt pathway is prominently involved, but clearly not in all cases. Surprisingly, despite in vitro demonstration that p27 and cyclin D1 lies downstream of PTEN and Akt, there was no correlation between p27 and cyclin D1 expression and PTEN or P-Akt status. Thus, in vivo, although PTEN and Akt play a prominent role in ovarian carcinogenesis, p27 and cyclin D1 might not be the primary downstream targets. Alternatively, these observations could also suggest that pathways involving other than Akt, p27 and cyclin D1 that lie downstream of PTEN play roles in ovarian carcinogenesis.

Fusion of a sequence from HEI10 (14q11) to the HMGIC gene at 12q15 in a uterine leiomyoma

Uterine leiomyoma, a benign smooth-muscle tumor of the myometrium, is the most commonly encountered neoplasm in women of reproductive age. Band q15 of chromosome 12 is often rearranged in benign mesenchymal tumors such as uterine leiomyomas, and the HMGIC gene, encoding a protein of the high-mobility-group (HMG), is present in that region. Using 3' rapid amplification of cDNA ends (3'RACE) experiments, we isolated an ectopic sequence that was fused to HMGIC in a uterine leiomyoma. Cloning of the fusion cDNA identified a gene termed rising dbl quote, left (low)homo sapiens enhancer of invasion 10" (HEI10) as the fusion partner. Radiation hybrid mapping revealed that the normal location of HEI10 is at 14q11. In the fusion transcript the first two exons of the HMGIC gene, which encode DNA-binding domains, were fused to the 3' portion of the HEI10 gene. This rearrangement implicates HMGIC in the tumorigenesis of uterine leiomyoma, and suggests that its fusion HMGIC product may play a role in mesenchymal differentiation.

Three aberrant splicing variants of the HMGIC gene transcribed in uterine leiomyomas

Cytogenetic aberrations involving chromosome region 12q13-15 occur frequently among benign mesenchymal tumors in humans, e.g., pleomorphic adenomas of the parotid gland, pulmonary chondroid hamartomas, lipomas, or uterine leiomyomas. HMGIC, a gene encoding a protein of the high-mobility group, has been identified as a target of those events. Using the 3' rapid amplification of cDNA ends (RACE) technique, we identified six different fusion transcripts of the HMGIC gene among 13 uterine leiomyomas; three of these variants had not been described before. Radiation-hybrid mapping located all three of the novel fusion transcripts in the same chromosomal region as the HMGIC gene. Cloning of the entire HMGIC gene in a genomic contig of P1-derived artificial chromosomes and cosmids revealed that the 3' portion of each novel fusion transcript contained cryptic exonic sequences (designated a, b, and c) present in intron 3 of the HMGIC gene. Thus, aberrant alternative splicing was responsible for abnormal HMGIC isoforms in those myomas. Identification of these novel variants suggested that aberrant splicing can join chromosomal translocation and inversion as a mechanism for producing abnormal HMGIC transcripts, and that separation of the DNA binding domains of HMGIC from its acidic carboxyl-terminal regulatory domain can lead to development of benign mesenchymal tumors.

Cultured keratinocytes from plectin/HD1-deficient epidermolysis bullosa simplex showed altered ability of adhesion to the matrix

Epidermolysis bullosa simplex associated with late onset of muscular dystrophy has been found to show defective expression of plectin, an intracytoplasmic protein in hemidesmosomes. In this report, we examined ability of cell-to-matrix attachment of cultured keratinocytes derived from a case with this disease by various cell biological methods, and compared it to that of normal keratinocytes. In cell adhesion assay, the patient keratinocytes showed more prominent short-time cell adhesion than normal keratinocytes. In contrast, the patient keratinocytes could be detached much easier than normal keratinocytes in cell detachment assay by treatment with dispase. In phagokinetic track assay, no apparent difference of cell migration was observed between the patient and normal keratinocytes. These results indicate that plectin-deficiency may up-regulate short-term cell contact and reduce stable cell-matrix adhesion at the epidermal basement membrane zone.

[A case of left occipital lobe hemorrhage in a patient with progressive systemic sclerosis: evaluation of cerebral angiography and histology]

Involvement of the central nervous system is uncommon in progressive systemic sclerosis, with only 2 reported cases associated with intracerebral hemorrhage detected by neuroimaging. A 55-year-old woman with a 10-year history of scleroderma presented with left occipital lobe hemorrhage manifesting as headache and vomiting. She had no signs of hypertension, diabetes mellitus and hyperlipidemia. CT and MRI, on admission, showed left occipital lobe hemorrhage with ventricular rupture and acute left subdural hematoma. Serial cerebral angiography was performed on day 0, day 7 and day 14, and found no evidence of aneurysm, arteriovenous multiformation or tumor stain in the left occipital lobe. However, the bilateral anterior cerebral arteries showed increasing segmental narrowing suggestive of vasculitis. Histological examination of a section from the brain cortex adjacent to the hemorrhage revealed no evidence of vasculitis, fibrinoid degeneration or amyloid deposition. Focal vasculitis may have occurred secondary to the homorrhagic lesion.

Biallelic inactivating mutations and an occult germline mutation of PTEN in primary cervical carcinomas

A tumor suppressor gene on chromosome sub-band 10q23.3, PTEN, is frequently mutated or deleted in a variety of human cancers. Germline mutations in PTEN, that encodes a dual-specificity phosphatase, have been implicated in two hamartoma-tumor syndromes that exhibit some clinical overlap, Cowden syndrome and Bannayan-Zonana syndrome. Although cervical cancer is not a known component of these two syndromes, loss of heterozygosity (LOH) of markers on chromosome arm 10q is frequently observed in cervical cancers. To determine the potential role that PTEN mutation may play in cervical tumorigenesis, we screened 20 primary cervical cancers for LOH of polymorphic markers within and flanking the PTEN gene, and for intragenic mutations in the entire coding region and exon-intron boundaries of the PTEN gene. LOH was observed in 7 of 19 (36.8%) cases. Further, one sample may have homozygous deletion. Three (15%) intragenic mutations were found: two were somatic missense mutations in exon 5, that encodes the phosphatase motif, and an occult germline intronic sequence variant in intron 7, that we show to be associated with aberrant splicing. All three samples with the mutations also had LOH of the wild-type allele. These data indicate that disruption of PTEN by allelic loss or mutation may contribute to tumorigenesis in cervical cancers. In cervical cancer, unlike some other human primary carcinomas, e.g., those of the breast and thyroid, biallelic structural PTEN defects seem necessary for carcinogenesis. Further, one in 20 unselected cervical carcinomas was found to have a germline PTEN mutation; it is unclear whether the patient with this mutation had Cowden disease or a related syndrome.

Molecular cloning and characterization of three novel cytochrome P450 2D isoforms, CYP2D20, CYP2D27, and CYP2D28 in the Syrian hamster (Mesocricetus auratus)

We cloned three novel cytochrome P450 (CYP) 2D cDNAs in the Syrian hamster (Mesocricetus auratus). Each clone contained an open reading frame of 1500 nucleotides encoding a protein of 500 amino acids. The deduced amino acid sequences of these had high identities with those of the other CYP2D members, therefore, the clones were assigned as CYP2D20, CYP2D27, and CYP2D28. Northern blot analysis showed that the CYP2D27 mRNA was expressed in liver, but not in kidney, small intestine, and brain, while the CYP2D20 and CYP2D28 mRNAs were not detected in these tissues examined. The expression of CYP2D27 mRNA in liver did not show sex difference and was not induced by either 3-methylcholanthrene or phenobarbital treatment. We characterized the enzyme activities of recombinant CYP2D27 expressed in COS-7 cells. The CYP2D27 protein had the bufuralol 1'-hydroxylase and debrisoquine 4-hydroxylase activities that are specific to the CYP2D subfamily.

Novel gene fusion of COX6C at 8q22-23 to HMGIC at 12q15 in a uterine leiomyoma

Cytogenetic analyses have shown that aberrations involving 12q13-15 are frequent chromosomal changes in a variety of human benign mesenchymal tumors, e.g., pleomorphic adenomas of the parotid gland, pulmonary chondroid hamartomas, lipomas, and uterine leiomyomas. Recently, the high-mobility group protein gene HMGIC was identified as the target gene affected by the 12q13-15 aberrations. Using 3' rapid amplification of cDNA ends experiments, we isolated novel ectopic sequences fused to HMGIC in a uterine leiomyoma. Cloning of the fusion cDNA identified the human cytochrome c oxidase subunit VIc (COX6C) gene on 8q22-23 as the fusion partner of HMGIC. Nucleotide sequences of the fusion transcript revealed that the first 3 exons of the HMGIC gene, encoding the 3 DNA binding domains, was fused to the exon 2 of the COX6C gene. The identification of a gene rearrangement suggests a role for HMGIC in tumorigenesis of uterine leiomyoma and suggests a possible involvement of HMGIC in mesenchymal differentiation. Genes Chromosomes Cancer 27:303-307, 2000.

Cloning and expression analysis of a new member of the cytochrome P450, CYP2A15 from the Chinese hamster, encoding testosterone 7alpha-hydroxylase

We cloned a new cytochrome P450 cDNA encoding testosterone 7alpha-hydroxylase in the Chinese hamster, designated CYP2A15 which shares significant amino acid sequence homology with members of the CYP2A subfamily. The CYP2A15 cDNA was isolated by screening a liver cDNA library and the sequence contains an open reading frame of 1482 nucleotides encoding a polypeptide of 493 amino acids with a calculated molecular mass of 56,295 Da. This is flanked by a 5'-untranslated region of 2 bp and a 3' untranslated region of 191 bp including the poly(A) tail. We determined the catalytic activity of CYP2A15 using microsomes obtained by transient expression of its cDNA in transfected COS-7 cells. The heterologously expressed CYP2A15 was found to hydroxylate testosterone at position 7alpha in a reconstituted system. RT-PCR experiments revealed that the mRNA of CYP2A15 was expressed in liver, but not detected in kidney, lung, or small intestine. The expression of CYP2A15 mRNA was slightly induced by treatment with either rifampicin or 3-methylcholanthrene.

Molecular cloning, heterologous expression, and characterization of a novel member of CYP2A in the Syrian hamster

The cDNA clone coding for a novel cytochrome P-450 2A subfamily member (CYP2A16) was isolated from a Syrian hamster liver cDNA library. The deduced amino acid sequence of CYP2A16 showed more than 90% identity with those of rat CYP2A3 and mouse CYP2A4/5. The catalytic activity of CYP2A16 was determined by transient expression of its cDNA in transfected COS7 cells and CYP2A16 was found to have the testosterone 2 beta-, 15 alpha-, and 15 beta-hydroxylases, coumarin 7-hydroxylase, and ethoxycoumarin O-deethylase activities. These enzymatic characteristics of CYP2A16 are different from those of other Syrian hamster CYP2A subfamily members, CYP2A8 and CYP2A9. Northern blot analysis showed that CYP2A16 was expressed in kidney and lung while most of the other CYP2A subfamily members have been reported to be expressed in liver and olfactory. These observations indicated that the Syrian hamster CYP2A16 had unique properties compared with those of other CYP2A subfamily members.

Two target regions of allelic loss on chromosome 9 in urinary-bladder cancer

Allelic losses on chromosome 9 are common in a wide variety of human tumors; moreover, two predisposing loci for some inherited cancer syndromes, i.e., familial malignant melanoma and Gorlin syndrome, have been identified on this chromosome. To define the location of putative tumor suppressor genes involved in cancer of the urinary bladder, 85 bladder cancers were examined for allelic loss at 18 microsatellite loci on chromosome 9. Correlations were also sought between loss of heterozygosity on chromosome 9 and several clinicopathological parameters. Allelic loss was observed in 54 of the tumors (64%) and deletion mapping identified two target regions; one at an interval on 9p21 flanked by D9S736 and D9S165, and the other at an interval on 9q31-34 flanked by D9S58 and D9S61. No subtle mutation was detected in the PTCH gene which lies in the latter interval. Allelic loss on chromosome 9 was observed frequently in low grade and non-invasive tumors as well as in tumors of more advanced phenotype. Inactivation of tumor suppressor genes lying in either of two regions of common deletion identified on chromosome 9 might affect carcinogenic mechanisms at an early stage of tumor development in the urinary bladder.

A novel positive regulatory element that enhances hamster CYP2A8 gene expression mediated by xenobiotic responsive element

CYP2A8 is a major form of cytochrome P-450 inducible by 3-methylcholanthrene in Syrian hamster liver. To identify DNA elements necessary for the transcriptional activation of the CYP2A8 gene, we analyzed the regulatory region of the CYP2A8 gene and conducted transient transfection experiments of CYP2A8-luciferase fusion plasmids in primary cultures of hamster hepatocytes. We analyzed up to -5 kb of the 5'-flanking region and found the region sufficient for the 3-methylcholanthrene-inducible gene expression. This region contained a consensus sequence for xenobiotic responsive element (XRE) between -2366 and -2349, which was shown to be essential for induction of the gene expression. Furthermore, we found a novel positive regulatory element for XRE-mediated gene expression (PREX) located upstream of the XRE. This element is not identified in any genes inducible by 3-methylcholanthrene so far reported. Without PREX, the XRE-mediated promoter activity was enhanced nearly 10-fold, whereas with PREX, the activity was enhanced 20-fold over the basal level. Gel mobility shift assays revealed specific binding of nuclear proteins to PREX. Mutations and deletions of PREX caused a loss of the binding and promoter-enhancing activities, respectively. Moreover, transient expression experiments showed that the enhancing activity of PREX was not observed in Drosophila Schneider's line 2 cells, which were shown to lack the PREX binding proteins.

A major phenobarbital-inducible P450 isozyme, CYP2A14, in the Chinese hamster liver: purification, characterization, and cDNA cloning

Phenobarbital, a potent inducer of CYP2B isozyme of cytochrome P450, induces mainly CYP2A but not CYP2B in the Chinese hamster liver. A major isozyme inducible by phenobarbital was purified by column chromatography from Chinese hamster livers. This isozyme, named P450CH2A-2 and designated CYP2A14, had in the reconstituted system high activities of 7-ethoxycoumarin O-deethylase (43 nmol/min/nmol P450) and aflatoxin B1 activation and a moderate activity of testosterone 15alpha-hydroxylase and coumarin 7-hydroxylase. The N-terminal amino acid sequence of the purified protein had a high homology with those of CYP2A proteins. cDNA of this isozyme was analyzed by screening a Chinese hamster liver cDNA library with cDNA of CYP2A1 as a probe, and the obtained clone encoded a protein of 494 amino acids with a calculated molecular mass of 56.4 kDa. The N-terminal amino acid sequence of 20 residues was identical to that derived from the purified protein. The deduced amino acid sequence of the clone had a high identity with most of CYP2A proteins (>65%) and thus was designated CYP2A14. Immunoblot and Northern blot analyses demonstrated that this isozyme was induced markedly by phenobarbital but not with 3-methylcholanthrene and constitutes one of the major components in livers of phenobarbital-treated Chinese hamsters.

Somatic mutations of the PTEN/MMAC1 gene in fifteen Japanese endometrial cancers: evidence for inactivation of both alleles

Loss of heterozygosity (LOH) of chromosome 10q is observed in approximately 40% of endometrial cancers. Mutations in PTEN/MMAC1, a gene recently isolated from the 10q23 region, are responsible for two dominantly inherited neoplastic syndromes, Cowden disease and Bannayan-Zonana syndrome. Somatic mutations of this gene have also been detected in sporadic cancers of the brain, prostate and breast. To investigate the potential role of this putative tumor suppressor gene in endometrial carcinogenesis as well, we examined 46 primary endometrial cancers for LOH at the 10q23 region, and for mutations in the entire coding region and exon-intron boundaries of the PTEN/MMAC1 gene. LOH was identified in half of the 38 informative cases, and subtle somatic mutations were detected in 15 tumors (33%). Our results suggest that of the genes studied so far in endometrial carcinomas, PTEN/MMAC1 is the most commonly mutated one, and that inactivation of both copies by allelic loss and/or mutation, a pattern that defines genes as "tumor suppressors," contributes to tumorigenesis in endometrial cancers.

Frequent allelic loss at 7p14-15 associated with aggressive histologic types of breast cancer

We examined 142 primary human breast cancers to determine their patterns of loss of heterozygosity (LOH) at 19 microsatellite markers over the entire length of chromosome 7. Allelic loss at one or more loci on the short arm of chromosome 7 was observed in 37 of the tumors (26%). We found a new target region of allelic loss on 7p between D7S1802 and D7S817 at 7p14-15. LOH on 7p was found more frequently in tumors of the invasive solid tubular and scirrhous type (31 of 87); 36%) than in other less aggressive types (2 of 27; 7%) (P = 0.0047). The results suggest that inactivation of putative tumor suppressor gene(s) located at 7p14-15 may play a role in the development and/or progression of primary breast cancers, particularly those of the invasive solid tubular and scirrhous type. Allelic loss was also found in 56 of 142 tumors on the long arm, and a commonly deleted region was defined between D7S522 and D7S1801 at 7q31.

cDNA cloning and expression of a novel CYP3A from the Syrian hamster, CYP3A31

A clone, encoding a cytochrome P450 protein consisting of 501 amino acids, was isolated from a cDNA library constructed from mRNA of Syrian hamster liver. The deduced amino acid sequence of this clone showed a high homology (65 to 81%) with other mammalian CYP3As and hence, this novel isozyme was named CYP3A31. By Northern blotting, using an oligonucleotide specific to CYP3A31, the mRNA for this isozyme was shown to be expressed constitutively in liver and induced by treatment with phenobarbital but repressed by 3-methylcholanthrene or dexamethasone treatments. The increase in mRNA expression by phenobarbital and decrease by dexamethasone corresponded to changes in CYP3A protein as analysed by Western blotting. These indicate that CYP3A31 might constitute one of the major CYP3A isozymes in the hamster.

Mapping of a new target region of allelic loss to a 2-cM interval at 22q13.1 in primary breast cancer

Allelic losses on chromosome arm 22q are frequently observed in human meningiomas and in carcinomas of the colon, ovary, and breast. Among 140 primary breast cancers we examined for loss of heterozygosity (LOH) at 16 polymorphic loci on the long arm of chromosome 22, 56 (40%) showed LOH for at least one locus. Eleven of these tumors had retained heterozygosity for markers proximal to the NF2 locus but showed LOH for markers distal to NF2. Deletion mapping indicated a new common region of deletion, 2-cM in extent, at q13.1 between Interleukin 2 receptor beta (IL2RB) and D22S279. Our results raise the possibility that one or more tumor suppressor genes associated with breast cancer may exist at 22q13.1. Comparison of these results with clinicohistological data indicated that allelic losses on 22q tend to occur more frequently in tumors of malignant histological types.

Cloning and characterization of Syrian hamster testosterone 7 alpha-hydroxylase, CYP2A9

We report here the cloning of a cDNA encoding testosterone 7 alpha-hydroxylase in the Syrian hamster, designated CYP2A9. Overlapping clones encoding Syrian hamster CYP2A9 were isolated by screening a liver cDNA library and by performing rapid amplification of cDNA ends polymerase chain reaction on the cDNA library. The sequence of the CYP2A9 cDNA contains an open reading frame of 1482 nucleotides encoding a polypeptide of 493 amino acids with a calculated molecular mass of 56,295 Da. The sequence is flanked by a 5'-untranslated region of 10 bp and a 3'-untranslated region of 178 bp including the poly(A) tail. The deduced amino acid sequence shares significant homology with members of CYP2A subfamily, notably with CYP2A1 and CYP2A12 which have testosterone 7 alpha-hydroxylase activity. We characterized the catalytic activity of CYP2A9 using microsomes obtained by transient expression of its cDNA in transfected COS-7 cells. CYP2A9 was found to hydroxylate testosterone at position 7 alpha. In Syrian hamster livers, a higher level of testosterone 7 alpha-hydroxylase activity as well as the mRNA of CYP2A9 in male than in female was obtained. The testosterone 7 alpha-hydroxylase activity and the mRNA level in liver were both decreased moderately by administration of 3-methylcholanthrene and slightly by administration of phenobarbital. In contrast, in kidney, both 3-methylcholanthrene and phenobarbital significantly decreased the mRNA level. These facts indicate that the regulation of the hamster testosterone 7 alpha-hydroxylase (CYP2A9) expression is different from that of the rat (CYP2A1) and hamster reported previously by other workers.

Production of antibody to hepatitis B surface antigen (anti-HBs) by murine hepatitis B virus carriers: neonatal tolerance versus antigen presentation by dendritic cells

The inability of hepatitis B virus (HBV) transgenic mice, which express abundant hepatitis B surface antigen (HBsAg) in sera from the neonatal period onwards, to produce antibody to HBsAg (anti-HBs) is considered to be due to defective function of lymphocytes. The defective function is thought to result from neonatal tolerance because antigenic challenge during the neonatal period is considered to be a tolerogenic event rather than an immunogenic one. However, a series of mixed culture experiments in vitro showed that lymphocytes taken from transgenic mice that had been injected with HBsAg in complete Freund's adjuvant (CFA) constitutively produced anti-HBs when cultured with dendritic cells from age-, sex- and major histocompatibility complex (MHC)-matched normal mice, but not when cultured with dendritic cells from transgenic mice. The expression of major histocompatibility complex (MHC) class II and B 7.2 (CD86) antigens on dendritic cells was significantly lower in transgenic mice compared with the same from the normal mice (P < 0.05). Treatment of transgenic mice with interferon-gamma (IFN-gamma) resulted in up-regulation of MHC class II on dendritic cells, and lymphocytes from HBsAg-injected transgenic mice produced anti-HBs in vitro when cultured with dendritic cells from IFN-gamma-treated transgenic mice, but not when cultured with the dendritic cells from untreated transgenic mice. These experiments have shown that defective function of antigen-presenting cells (APC), not immunogenic tolerance, is responsible for the inability of murine HBV-carriers to produce anti-HBs. Production of anti-HBs by lymphocytes from HBsAg-injected transgenic mice in the presence of dendritic cells that express higher levels of MHC class II and CD86 antigens has inspired optimism that a more effective vaccine therapy can be developed for chronic HBV-carriers, injecting vaccine containing HBsAg with modulator(s) of APC function of dendritic cells.

Clinicopathological characteristics of the focal and segmental form of idiopathic membranous nephropathy: comparison with the typical form of this disease

Although idiopathic membranous nephropathy (IMN) is thought to represent a diffuse glomerulopathy, it was found that three of 31 children histologically diagnosed as IMN showed focal and segmental deposition of immunoglobulin G (IgG) and C3 on the glomerular capillary walls. The present study attempted to comparatively investigate clinical and pathological features of the diffuse group and the focal segmental group in 31 IMN children. Immunofluorescence study revealed that 28 of 31 IMN exhibited diffuse granular deposition of IgG along glomerular capillary walls. In contrast, focal and segmental deposition of IgG and C3 was noted in three children with IMN. In addition, focal and segmental electron-dense deposits were identified in these cases. In two children of the focal segmental group, immunofluorescent patterns of IgG deposition were unchanged even at the second biopsy. The focal segmental form of IMN tended to occur in younger children than diffuse IMN. However, other clinical parameters such as the range of proteinuria, hematuria, serum albumin and prognosis did not show any significant differences between both groups. Electrophoretic profiles of urinary proteins on sodium dodecylsulfate-polyacrylamide gel electrophoresis were not different between both groups. It is proposed that the focal segmental form of IMN may have a distinctive glomerulopathy from the typical form of IMN.

Placebo-controlled trial of vaccination with hepatitis B virus surface antigen in hepatitis B virus transgenic mice

BACKGROUND/AIMS

Treatment of hepatitis B virus carriers by vaccine containing hepatitis B surface antigen with Pre-S protein and HBsAg/ anti-HBs complex has been reported and these studies have constituted a new and promising concept for the treatment of HBV-carriers. The present communication, a placebo-controlled trial of vaccination in HBV-transgenic mice, was designed to examine the impact of vaccination using a high dose of HBsAg for a duration of 12 months to achieve further insights about the dose, duration and effectiveness of vaccine therapy. Another aim of this study was to analyse the mechanism underlying the antiviral and immunomodulatory potentiality of vaccine therapy in HBV-transgenic mice.

METHODS

HBV-transgenic mice positive for HBV DNA, hepatitis B surface antigen and hepatitis B e antigen in sera received either HBV-vaccine containing HBsAg in complete Freund's adjuvant (CFA), intraperitoneally, once a month for 12 consecutive months (vaccine recipients), or only CFA, intraperitoneally once in a month for 12 consecutive months (placebo recipients). Thirty-two vaccine-recipient and 16 placebo-recipient HBV-transgenic mice were injected, checked and followed on a monthly basis for the entire duration of 12 months.

RESULTS

Of the 32 transgenic mice from the vaccine-recipient group, 25 became completely negative for HBsAg and 30 for HBeAg. Five mice developed anti-HBs in sera after the observation period of 12 months. Semiquantitative estimation of HBV DNA by polymerase chain reaction showed that vaccination resulted in a decrease of HBV DNA in sera. Placebo-recipient transgenic mice did not show any significant change in the titres of HBV markers after receiving 12 monthly injections of CFA. Interleukin-2 could be detected in sera from vaccine-recipient transgenic mice, but not in placebo-recipient transgenic mice.

CONCLUSIONS

Vaccination with a high dose of HBsAg in adjuvant over a long period had a significant antiviral as well as immunomodulatory potential in HBV-transgenic mice. This inspires optimism that vaccine alone or in combination with antiviral agents can be used successfully for the treatment of human HBV-carriers.

Serum from normal elderly individuals contains anti-basement membrane zone antibodies

BACKGROUND

Bullous pemphigoid is an autoimmune bullous disease with circulating anti-basement membrane zone antibodies, and it commonly affects elderly individuals; however, the reasons for the late onset of the disease are unclear.

DESIGN

The anti-basement membrane zone antibodies in serum samples from normal elderly subjects were compared with those in serum samples from normal young subjects.

PARTICIPANTS

Serum samples from 32 elderly and 28 young normal individuals and 10 patients with bullous pemphigoid were used.

INTERVENTIONS

Indirect immunofluorescence against guinea pig esophagus or human salt-split epidermis and immunoblotting against human and guinea pig epidermis were performed.

RESULTS

Serum samples from young individuals were devoid of anti-basement membrane zone antibodies against guinea pig esophagus and human salt-split epidermis. Among 32 serum samples from elderly patients, 6 cases (19%) were positive for anti-basement membrane zone antibody for guinea pig esophagus, and in those the titers were 10 in 3 cases and 40, 80, and 320 in the others. One case was positive against human split epidermis at a titer of 10. An immunoblotting analysis showed that the antigenicity of the 230-kd and 180-kd bullous pemphigoid antigen from guinea pig epidermal extract was similar to that of human epidermal extract; however, the molecular weight was slightly different. The 4 cases of elderly serum that recognized guinea pig esophagus basement membrane zone showed positivity with the 230-kd peptide in the guinea pig epidermal extract; however, they were negative with the human epidermal extracts. Direct immunofluorescence observation of these cases showed that deposition of IgG or C3 was not present in cryostat sections from flexor arm surfaces.

CONCLUSIONS

The serum samples from elderly subjects possessed a relatively high incidence of anti-basement membrane zone antibodies detectable with guinea pig esophagus as substrate. This observation of a specific immune defect in elderly individuals might explain why they are more susceptible to developing bullous pemphigoid.

Okadaic acid potentiates 3-methylcholanthrene-induced CYP2A8 gene expression in primary cultures of Syrian hamster hepatocytes: possible involvement of activator protein-1

In Syrian hamster liver, treatment with 3-methylcholanthrene (3-MC) markedly induces an isozyme of cytochrome P450 (CYP), CYP2A8. To elucidate the mechanism of this induction, we studied the effect of okadaic acid (OA), an inhibitor of serine threonine protein phosphatases 1 and 2A, on 3-MC-induced CYP2A8 expression in primary cultures of Syrian hamster hepatocytes. The addition of OA to the cultured hepatocytes at a concentration of 1 nM potentiated 3-MC- (0.1 and 1 microM) induced expression of mRNA and protein of CYP2A8 and its associated coumarin 7-hydroxylase activity. In addition, OA not only induced c-fos and jun-D mRNA, components of transcription factor activator protein-1 (AP-1), with an increase in AP-1 binding activity in the nucleus, but also activated AP-1-dependent gene transcription in the hepatocytes. The dose-dependent effect of OA on 3-MC-induced CYP2A8 expression corresponded to that of OA on c-fos and jun-D mRNA induction and on the activation of AP-1-dependent gene transcription. The expression of c-fos and jun-D mRNA induced by OA preceded the expression of CYP2A8 mRNA potentiated by co-treatment with 3-MC and OA. Treatment with anisomycin and cycloheximide also potentiated 0.1 microM 3-MC-induced coumarin 7-hydroxylase activity, induced c-fos and jun-D mRNA expression, and activated AP-1-dependent gene transcription in the hepatocytes. Furthermore, 3-MC-induced CYP2A8 expression was potentiated in the hepatocytes transfected with c-Jun expression plasmid. These results suggest that AP-1, inducible by serine threonine protein kinase, may be one of the components of the signal transduction system from 3-MC to CYP2A8 gene expression.

Response to interferon in chronic hepatitis C due to mixed genotype infection

We examined the response to interferon (IFN) in patients with chronic hepatitis C (CHC) due to two different genotypes of hepatitis C virus (HCV) infection. Among 64 CHC patients studied, one (2%) had HCV-RNA genotype I, 36 (56%) had genotype II, 19 (30%) had genotype III, 2 (3%) had genotype IV and 6 (9%) had both genotypes II and III. There was no significant difference in age, sex, history of blood transfusion and liver histology among patients with genotypes II, III and II + III. The HCV-RNA titre of genotype II patients was significantly higher than that of genotype III patients (P < 0.05). However, there was no significant difference in the HCV-RNA titre between genotype II + III and the other groups. The complete response rate achieved with IFN therapy was significantly higher in genotype III patients (74%) than in genotype II patients (17%; P < 0.01). Of the six patients with genotype II + III, a complete response to IFN was only achieved by two patients (33%), both of whom had a low HCV-RNA titre ( < or = 10(4.5) copies/mL) and HCV serotype 2. The remaining four patients had HCV serotype 1 and three of the patients had a high HCV-RNA titre ( > or = 10(5) copies/mL). The HCV genotype III was lost in two patients after IFN therapy. These data suggest that HCV-RNA titre and HCV serotype are important factors for predicting the efficacy of IFN therapy in patients with mixed genotype infection and show direct evidence of higher susceptibility towards CHC of patients with genotype III than genotype II.

Serum tumor necrosis factor in mesangial IgA glomerulonephritis with macroscopic hematuria in children

Tumor necrosis factor (TNF)-alpha and interferon (INF)-gamma levels were measured in the sera obtained from 29 patients with IgA glomerulonephritis (IgA GN), 8 patients with minimal change nephrotic syndrome (MCNS) and 12 patients with upper respiratory tract infection (URI) without renal diseases in children. The serum TNF-alpha level of IgA GN was 123.0 +/- 175.4 pg/ml, MCNS was 4.9 +/- 4.0 pg/ml and URI was 10.5 +/- 4.5 pg/ml respectively. The serum TNF-alpha level of IgA GN was significantly higher than those of MCNS and URI. The serum TNF-alpha level of URI was on the high trend compared with that of MCNS, but was not statistically significant. Although the TNF-alpha level was related to mesangial cell proliferation in patients with IgA GN, it was unrelated to the grade of mesangial matrix expansion and magnitude of proteinuria. In 17 patients with IgA GN having macroscopic hematuria, the serum TNF-alpha level was 190.5 +/- 201.6 pg/ml, and in other IgA GN patients with microscopic hematuria it was 37.4 +/- 75.7 pg/ml. The serum TNF-alpha level of IgA GN with macroscopic hematuria was significantly higher than that with microscopic hematuria. In 6 patients with IgA GN with macroscopic hematuria, the serum TNF-alpha level was significantly decreased after macroscopic hematuria disappeared. The mean serum IFN-gamma level of IgA GN was 0.3 +/- 0.6 IU/ml, and MCNS was not detectable. Although the serum IFN-gamma level was related to mesangial cell proliferation in patients with IgA GN, it was unrelated to magnitude of proteinuria, the grade of mesangial matrix expansion and also the presence or absence of macroscopic hematuria. We suggest that macroscopic hematuria of IgA GN was closely related to the serum TNF-alpha level.

Microfluorometric study of nuclear DNA in normal human epidermis

Quantitative and qualitative changes of nuclear DNA were analyzed by microfluorometry in normal human epidermis during terminal differentiation. Normal human epidermis from five healthy volunteers was separated by an EDTA-trypsin method and fractionated by Percoll density gradient. Staining was carried out with either Feulgen reaction, Acridine Orange or 4'-6-diamidino-2-phenylindole (DAPI). When the cells with lower density (granular layer cells) were stained with Acridine Orange or DAPI, the greatest population was found at lower value of DNA than that in the cells stained with Feulgen reaction. After thermal denaturation procedure, a ratio of double-stranded DNA to single-stranded DNA was highest in the cells with lower density. These results seem to suggest the qualitative and quantitative changes of nuclear DNA during terminal differentiation of human epidermal keratinocytes.

RNA polymerase III dependence of the human L1 promoter and possible participation of the RNA polymerase II factor YY1 in the RNA polymerase III transcription system

From the general views of the eukaryotic transcription systems, L1 (or L1-like) retrotransposons that encode some proteins are unusual. L1, unlike other protein-coding elements, is transcribed through an internal promoter. And the L1 internal promoter, unlike other internal promoters, is thought to be RNA polymerase II (pol II) dependent, because the L1 transcript has a large size (approximately 6 kb), protein coding capacity and a 3' terminal polyadenylation signal followed by a poly(A) tail, and also because transcription from the promoter of Drosophila L1-like element jockey was highly sensitive to alpha-amanitin. However, our in vitro transcription study reveals that transcription from the human L1 promoter is highly sensitive to tagetitoxin, a selective inhibitor of RNA polymerase III (pol III), but insensitive to 1 micrograms/ml of alpha-amanitin, indicating that the human L1 promoter is pol III-dependent. The pol III dependence is further supported by our observation that L1 and pol III-dependent tRNA gene promoters share a common nuclear factor YY1. There is evidence that YY1 is also a pol II transcription factor. We thus propose that YY1 is a possible member of the pol III transcription system.

Interferon therapy for patients more than 60 years of age with chronic hepatitis C

Nineteen patients aged > 60 years with chronic hepatitis C (CHC) received interferon (IFN) therapy and a complete response (CR) was achieved by five of them (26%). The incidence of CH with severe fibrosis in this elderly group was significantly higher than in another 52 patients with CHC who were < 60 years of age (the younger group; P < 0.05). There was no significant difference in the hepatitis C virus (HCV) genotype distribution between the elderly group and the younger group. However, the HCV-RNA titre was significantly higher in the elderly group than in the younger group (P < 0.05). There was no significant difference in the efficacy rate of IFN in the elderly and younger groups after standardization of the background factors. In the elderly group, the HCV-RNA titre was significantly lower in the patients achieving CR than in those with no response (P < 0.05). These data suggest that elderly patients with a low HCV-RNA titre can still respond well to IFN therapy.