Lzts1 controls both neuronal delamination and outer radial glial-like cell generation during mammalian cerebral development.

In the developing central nervous system, cell departure from the apical surface is the initial and fundamental step to form the 3D, organized architecture. Both delamination of differentiating cells and repositioning of progenitors to generate outer radial glial cells (oRGs) contribute to mammalian neocortical expansion; however, a comprehensive understanding of their mechanisms is lacking. Here, we demonstrate that Lzts1, a molecule associated with microtubule components, promotes both cell departure events. In neuronally committed cells, Lzts1 functions in apical delamination by altering apical junctional organization. In apical RGs (aRGs), Lzts1 expression is variable, depending on Hes1 expression levels. According to its differential levels, Lzts1 induces diverse RG behaviors: planar division, oblique divisions of aRGs that generate oRGs, and their mitotic somal translocation. Loss-of-function of lzts1 impairs all these cell departure processes. Thus, Lzts1 functions as a master modulator of cellular dynamics, contributing to increasing complexity of the cerebral architecture during evolution.

Persistent elevation of serum alanine aminotransferase levels leads to poor survival and hepatocellular carcinoma development in type 1 autoimmune hepatitis.

BACKGROUND: Although the prognosis of type 1 autoimmune hepatitis is generally good with immunosuppressive treatment, the disease progresses in some patients despite the treatment. The prognosis may be determined by the clinical course. AIM: To evaluate the long-term prognosis and assess the predictive factors for a serious event, including the development of hepatocellular carcinoma or death. METHODS: Sixty-nine patients with type 1 autoimmune hepatitis were prospectively followed up regularly, with a median follow-up period of 96 months (49-201 months). RESULTS: During the follow-up period, three patients (4%) developed hepatocellular carcinoma, and two of these three patients died. Another patient died of liver failure. The 10-year survival rate was 98%, and the 10-year hepatocellular carcinoma-free rate was 93%. The four patients experiencing a serious event received higher maintenance doses of corticosteroid during their follow-up periods than those did not. However, serum alanine aminotransferase levels during the follow-up period were higher in these four patients than in the others. CONCLUSIONS: Persistent elevation of serum alanine amniotransferase levels during the follow-up period, rather than factors existing prior to medical treatment is considered to be an important prognostic factor, and it is indicated that poor outcomes may result from the resistance to immunosuppressive treatment.

Clinical characteristics of fulminant-type autoimmune hepatitis: an analysis of eleven cases.

BACKGROUND: Although a few adult cases of fulminant-type autoimmune hepatitis have been reported, their clinical features and prognosis have remained uncertain. AIM: To assess the clinical features and prognosis of patients with fulminant-type autoimmune hepatitis. METHODS: Eleven patients (10%) diagnosed with fulminant-type autoimmune hepatitis in accordance with the 1999 criteria of the International Autoimmune Hepatitis Group were analysed. RESULTS: All 11 patients were female, with a median age of 53 years. Five patients survived without liver transplantation, one received a liver transplantation, and five died without liver transplantation. Nine patients (82%) survived for 2 weeks or more following diagnosis, without liver transplantation. Except for the patient receiving a liver transplantation, serum total bilirubin levels measured during the clinical course were significantly higher in non-survivors than in survivors, although the accompanying serum alanine aminotransferase levels measured for the two groups were similar. Most significantly, serum total bilirubin levels in non-survivors worsened during days 8-15, while levels in survivors improved during the same period. CONCLUSIONS: The short-term prognosis for patients with fulminant-type autoimmune hepatitis may be good. However, patients whose serum total bilirubin levels worsen during days 8-15 should be considered for liver transplantation.

A large-scale Agrobacterium-mediated transformation procedure with a strong positive-negative selection for gene targeting in rice (Oryza sativa L.).

A large-scale transformation procedure handling an adequate number of stable transformants with highly efficient positive-negative selection is a necessary prerequisite to successful gene targeting by homologous recombination, as the integration of a transgene by somatic homologous recombination in higher plants has been reported to be 10(-3) to 10(-5) compared with random integration by non-homologous end joining. We established an efficient and large-scale Agrobacterium-mediated rice transformation protocol that generated around 10(3) stable transformants routinely from 150 seeds and a strong positive-negative selection procedure that resulted in survivors at 10(-2) using the gene for diphtheria toxin A fragment as a negative marker. The established transformation procedure provides a basis for efficient gene targeting in rice.

Laparoscopic features of primary biliary cirrhosis in AMA-positive and AMA-negative patients.

BACKGROUND AND STUDY AIMS: Antimitochondrial antibody (AMA)-negative primary biliary cirrhosis (PBC) has been difficult to diagnose. Laparoscopic features of AMA-negative PBC were evaluated in comparison with those of AMA-positive PBC and autoimmune hepatitis. PATIENTS AND METHODS: 71 patients who fulfilled the diagnostic criteria for PBC were enrolled in the study; 48 were AMA-positive and 23 were AMA-negative. As a disease control, 46 autoimmune hepatitis patients were included. Both the frequency and specificity of each laparoscopic finding were evaluated. A laparoscopic scoring system was introduced, which used, common and uncommon laparoscopic findings, and was evaluated for the diagnosis of AMA-negative PBC. RESULTS: The characteristic laparoscopic findings for AMA-positive PBC were yellowish-white marking (92 %), dark-brown discoloration (73 %), gentle undulation (67 %), reddish patch (38 %), and yellowish-white nodules (32 %). On the other hand, laparoscopic findings such as trench-like depression, reddish markings, and wide and small depressions were uncommon in PBC compared with autoimmune hepatitis. The frequencies of characteristic and uncommon laparoscopic findings did not differ statistically between AMA-positive and AMA-negative PBC, but were different between AMA-positive or AMA-negative PBC and autoimmune hepatitis. Scores based on common and uncommon laparoscopic findings were 5.5 +/- 1.5 (mean +/- SD) in AMA-positive PBC, 5.6 +/- 2.0 in AMA-negative PBC, and - 0.30 +/- 0.5 in autoimmune hepatitis. CONCLUSION: The laparoscopic findings in AMA-negative PBC did not differ from those of AMA-positive PBC. A laparoscopic scoring system may be helpful in the diagnosis of AMA-negative PBC.

Evaluation of metastatic potential of gastric tumors by staining for proliferating cell nuclear antigen and chromosome 17 numerical aberrations.

BACKGROUND: Aberrations in chromosome 17 are important in carcinogenesis. We recently reported that numerical aberrations in chromosome 17 were associated with tumor progression in gastric cancer. The aim of this study was to determine the biological characteristics of gastric tumor cells with chromosome 17 numerical aberrations. METHODS: Gastric tumor sections (n = 105) and metastatic lymph nodes (n = 16) were stained simultaneously for PCNA (proliferating cell nuclear antigen) and chromosome 17 centromere. Cancers were classified as follows: Group 1: PCNA(+) and numerical chromosomal aberration(+); Group 2: PCNA(-) and numerical chromosomal aberration(+); Group 3: PCNA(+) and numerical chromosomal aberration(-); and Group 4: PCNA(-) and numerical chromosomal aberration(-). RESULTS: The frequency of Group 1 cells correlated with lymphatic invasion (P < .0001), lymph node metastasis (P < .0001), and venous invasion (P < .01). The frequency of these cells in gastric lesions was lower than in metastatic lymph nodes (P < .01). Logistic regression analysis identified the depth of invasion followed by the frequency of Group 1 cells were two of the most significant independent factors that could predict lymph node metastasis and lymphatic invasion. CONCLUSIONS: The frequency of gastric tumor cells positive for PCNA and chromosome 17 numerical aberrations may be an indicator of the metastatic potential of gastric cancers.

Solvent-induced dimensional changes in EDTA-demineralized dentin matrix.

The purpose of this study was to test the null hypothesis that the re-expansion of dried matrix and the shrinkage of moist, demineralized dentin is not influenced by polar solvents. Dentin disks were prepared from midcoronal dentin of extracted human third molars. After complete demineralization in 0.5M of EDTA (pH 7), the specimens were placed in the well of a device that measures changes in matrix height in real time. Dry, collapsed matrices were created by blowing dry N(2) on the specimens until they shrank to a stable plateau. Polar solvents [water, methanol, ethanol, n-propanol, n-butanol, formamide, ethylene glycol, hydroxyethyl methacrylate (HEMA), or mixtures of water-HEMA] as model primers then were added and the degree of re-expansion measured. These same solvents also were applied to moist, expanded matrices and the solvent-induced shrinkages measured. Regression analysis was used to test the correlations between matrix height and Hansen's dispersive, polar, hydrogen bonding, and total solubility parameters (delta(d), delta(p), delta(h), delta(t)). The results indicate that water-free polar solvents of low hydrogen bonding (H-bond) ability (e.g., neat HEMA) do not re-expand dried matrices and that they shrink moist matrices. When HEMA was mixed with progressively higher water concentrations, the model water-HEMA primers expanded the dried matrix in proportion to their water concentrations and they produced less shrinkage of moist matrices. Solvents with higher H-bonding capacities (methanol, ethanol, ethylene glycol, formamide, and water) re-expanded the dried matrix in proportion to their solubility parameters for H-bonding (delta(h)). They also induced small transient shrinkages of moist matrices, which slowly re-expanded. The results require rejection of the null hypothesis.

Laparoscopic findings in primary sclerosing cholangitis.

BACKGROUND AND STUDY AIMS: Primary sclerosing cholangitis (PSC) is a cholestatic disease characterized by segmental narrowing and dilatation of bile ducts. Few studies have been performed on the laparoscopic findings associated with this disease, and the present study was intended to assess the usefulness of laparoscopy for the diagnosis and staging of PSC. PATIENTS AND METHODS: Six patients were examined by laparoscopy with liver biopsy. Repeated laparoscopy was performed in three patients. RESULTS: Laparoscopy revealed coarse surface irregularity and discoloration. Surface irregularity was classified into four grades: smooth, shallowly depressed, undulated, and nodular. The affected area showed whitish yellow discoloration. The discolored area was demonstrated as a poorly stained area by intravenous injection of indocyanine green (ICG). Lobular markings became apparent because of the yellow color change in the portal tract, resulting in a leopardskin-like appearance. Lymph-vessel dilatation was seen in advanced stages. Repeated laparoscopy of a patient without treatment demonstrated a progression from a smooth surface to a shallow depression with leopardskin-like markings. On the other hand, the two patients treated with immunosuppressive agents showed improvement of liver swelling and disappearance of the leopardskin-like markings and lymph-vessel dilatation. CONCLUSIONS: Laparoscopy may provide useful information for the diagnosis and staging of PSC.

Mallory-Weiss syndrome with severe bleeding: treatment by endoscopic ligation.

There is no consensus as to the best treatment for Mallory-Weiss tears with severe bleeding. Endoscopic ligation is an inexpensive, readily available, and easily learned technique, in contrast to conventional thermocoagulation or hemoclipping. To evaluate the utility of endoscopic ligation, we performed this technique during emergency endoscopy to treat severe bleeding from Mallory-Weiss tears in four patients in our hospital with continuous active bleeding from Mallory-Weiss tears. The patients were all male with an average age of 40.5 years. Symptoms associated with increased intra-abdominal pressure, including retching and vomiting were reported by all patients. The bleeding points were aspirated and controlled by endoscopic ligation, and complete hemostasis was achieved in all cases. We conclude that endoscopic ligation is easy to perform and may provide an alternative treatment for severe bleeding from Mallory-Weiss tears.

Antisense waxy genes with highly active promoters effectively suppress waxy gene expression in transgenic rice.

To regulate Waxy (Wx) gene expression by introducing antisense genes, we connected the 2.3 kb Wx cDNA having 450 bp of the Wx first intron in reverse orientation to rice Wx and maize alcohol dehydrogenase1 (Adh1) promoters and used these constructs to transform rice plants. Of 10 independent transgenic lines analysed, four lines showed various degrees of reduction in amylose and WAXY (WX) protein levels in the endosperm. In two transgenic lines, complete absence of amylose was observed which made the seeds opaque white like glutinous rice (amylose-deficient waxy (wx) mutant). In one of the transgenic lines, A1 line, the presence of the antisense Wx gene cosegregated with reduction of amylose content in the endosperm. In the same line, a reduction in the level of endogenous Wx mRNA was observed in immature endosperm. Interestingly, this reduction was observed only with mature spliced transcripts but not with unspliced transcripts. Reduced amylose synthesis was also observed in pollen grains of four transgenic lines. These results suggest that integrated antisense Wx gene caused a reduction in amylose synthesis in endosperms and pollen grains of transgenic rice carrying the antisense Wx cDNA. These results indicate that manipulation of starch and other carbohydrates in rice grain is possible using antisense genes.

Clinical and histopathological features of colonic stromal tumor in a child.

Neoplasms of the colonic submucosa are rare in children. Gastrointestinal stromal tumors (GISTs) are undifferentiated tumors, usually diagnosed by immunohistochemistry. We report a 4-year-old girl with a submucosal GIST of the ascending colon, which was detected by computed tomography. Diagnosis after ileocecal resection was established by histology. In addition, sections were examined immunohistochemically, using antibodies against vimentin, desmin, alpha-smooth muscle actin, S100, neuron-specific enolase, c-kit, and CD34. Hematoxylin and eosin-stained sections showed interlacing fascicles with occasional palisades of epithelioid and spindle cells. The tumor cells were positive for vimentin and CD34. To our knowledge, this is the first reported case of colonic stromal tumor in a child.

Obturator hernia: the usefulness of emergent computed tomography for early diagnosis.

The diagnosis of obturator hernia is difficult, and delayed treatment is associated with serious complications. Recently, computed tomography (CT) has been used successfully for establishing a correct diagnosis. We encountered nine cases of obturator hernia from 1988 to 1997. All the patients were elderly women. In six of them, a correct diagnosis was established by emergent CT scan. In two of the remaining cases, diagnosis could not be established because of unavailability of CT, and the other patient was diagnosed correctly based on clinical features, including a positive Howship-Romberg sign. Surgical repair was performed successfully. One patient died postoperatively because of septicemia associated with anastomotic leakage. Our cases indicate that emergent CT scan is useful for the diagnosis of obturator hernia, particularly in elderly patients presenting with ileus of unknown origin.

Higher frequencies of numerical aberrations of chromosome 17 in primary gastric cancers are associated with lymph node metastasis.

We investigated the correlation between the frequency of numerical aberrations of chromosome 17 and clinicopathological features of gastric cancer. The copy number of chromosome 17 was examined with fluorescence in-situ hybridization (FISH) in frozen specimens from 100 primary gastric cancers. Chromosomal numerical aberrations were diagnosed as chromosomal loss (single signal) or gain (triple or more signals), in each cell. The frequency of numerical aberrations of chromosome 17 correlated significantly with the depth of invasion (P < 0.01), lymph node metastasis (P < 0.0001), lymphatic invasion (P < 0.001), and venous invasion (P < 0.01). Numerical aberrations of chromosome 17 were associated with lymph node metastasis in 32 early gastric cancers. Multiple regression analysis identified the depth of invasion and numerical aberrations of chromosome 17 as independent significant determinants of lymph node metastasis. Our findings suggest that alterations in chromosome 17 may be linked with tumor progression in primary gastric cancer. Our results also indicate that numerical aberrations of chromosome 17 detected by FISH provide important information about the malignant potential (in particular, lymph node metastasis) of primary gastric cancer.

Effects of propionyl-L-carnitine on cardiac dysfunction in streptozotocin-diabetic rats.

The effects of orally administered propionyl-L-carnitine on cardiac dysfunction in rats with streptozotocin-induced diabetes were investigated. Wistar male rats were divided into four groups: untreated normal, propionyl-L-carnitine (daily for 4 weeks with 3 g/kg orally) -treated normal, untreated diabetic, propionyl-L-carnitine-treated diabetic. Four weeks after streptozotocin administration, plasma lipid levels were increased and myocardial carnitine content was decreased in untreated diabetic rats. These changes were significantly reversed by the propionyl-L-carnitine treatment. Assessment of cardiac function with isolated perfused working hearts revealed a depression of left ventricular developed pressure as well as both maximum positive and negative dP/dt in untreated diabetic as compared with that in normal hearts. Cardiac function at the higher left atrial filling pressures in the propionyl-L-carnitine-treated diabetic rats was improved significantly compared to that in untreated hearts. The data thus suggest that oral administration of propionyl-L-carnitine can reduce abnormalities of cardiac function, correlated with a significant increase in myocardial carnitine content and improved lipid metabolism in terms of lowered plasma lipids.

Transposon tagging in rice.

To develop an efficient gene isolation method for rice we introduced the maize Ac/Ds system into rice. Extensive analysis of their behavior in rice for several generations indicated that Ac and Ds in the presence of Ac transposase gene actively transpose in rice. A wide spectrum of mutations affecting growth, morphogenesis, flowering time and disease resistance have been obtained in the population carrying Ac/Ds and some of them were genetically analyzed. Main efforts are currently being made to isolate genes responsible these mutations. In addition, a number of Ac/Ds were mapped on chromosomes and mapped elements will be used in the future for directed tagging of genes with known chromosomal positions.

[p53 alterations and chromosome 17 aberrations in non-small cell lung cancer].

We studied the relationship between DNA index, numerical abberation of chromosome 17 and alterations of the p53 gene in 23 non-small cell lung cancers. Diploid and aneuploid cells from 23 non-small cell lung cancer with DNA aneuploidy were flow sorted into each cell population using FACStar(plus). They were examined by PCR-SSCP analysis for p53 mutation and by microsatellite analysis for loss of heterozygosity at TP53 locus (17p13.1). They were also analyzed by FISH for copy number of chromosome 17. p53 mutations were found in aneuploid cells from the 11 cases (48%). Among them, 8 cases were informative at TP53 locus, and all showed loss of heterozygosity. Aneuploid cells from 16 cases exhibited gain of chromosome 17 copy number in FISH analysis. DNA index was significantly associated with th mean copy number of chromosome 17, suggesting that the number of chromosome 17 changed with DNA index. There were no associations between p53 mutation and DNA index or mean copy number of chromosome 17. In some cases, we also analyzed structural abberation of short arm of chromosome 17 by FISH using p53-cosmid (17p13.1) and Distal 17p (17p13.3-ptel) probes. The p53 gene located on the increased chromosome 17 was lost due to point mutation or deletion of 17p.

A type I element composed of the hexamer (ACGTCA) and octamer (CGCGGATC) motifs plays a role(s) in meristematic expression of a wheat histone H3 gene in transgenic rice plants.

Type I element (CCACGTCACCGATCCGCG) is a well-conserved regulatory element found in proximal promoter region of a certain class of plant histone genes, that is composed of two independent cis-acting elements of the hexamer (ACGTCA) and the reverse-oriented octamer (GATCCGCG) motifs. To investigate functional role(s) of the type I element in regulation of a wheat histone H3 gene (TH012) promoter activity in vivo, base substitution mutations were introduced into the element and activities of the mutated promoters were examined in cultured rice cells, and in regenerated roots and anther walls of transgenic rice plants by employing a GUS reporter system. Mutations of each or both of the hexamer and the octamer motifs caused a reduction in the promoter activity in protoplasts transfected transiently or stably transformed calli. The mutation of the octamer motif with or without the mutation of the hexamer motif caused a marked reduction of the promoter activity in the root meristem of transgenic rice although the mutation of the hexamer motif alone caused a weak reduction. In contrast to these results, no effect of the mutations of either the hexamer or the octamer motif was found in the anther wall in which replication-independent activity of the H3 promoter was observed. Our results suggested that the hexamer and the octamer motifs may play important role(s) in regulation of replication-dependent but not of replication-independent expression of the wheat histone H3 gene.

Proximal promoter region of the wheat histone H3 gene confers S phase-specific gene expression in transformed rice cells.

The cis-regulatory elements that confer cell cycle-dependent expression to the wheat histone H3 gene were investigated in rice cells (Oc strain) transformed with H3/GUS chimeric genes. 5' deletion mutants of the H3 promoter region (from -1711, -908 or -185 to +57 relative to the transcription start site) were joined to the coding sequence of the bacterial beta-glucuronidase (GUS) gene then introduced stably into rice cells. S1 analyses of the RNA from transformed rice cells whose cell cycles had been synchronized by treatment with aphidicolin showed that the steady-state levels of the transcripts from chimeric genes were altered with the change in DNA synthesis and the content of rice H3 mRNA throughout the cell cycle. Even though H3 promoter activity decreased as 5' deletion proceeded, transcripts from the chimeric genes showed increases, as much as 10-fold 1 h after release from the aphidicolin block, which were rapidly lost over the next 4 h. The results suggest that the 242 bp sequence from -185 to +57, which contains the basal promoter region, confers the S phase-specific expression of the H3 gene and that the upstream sequence from position -186 is required for the full activity of this promoter.

Trans-activation and stable integration of the maize transposable element Ds cotransfected with the Ac transposase gene in transgenic rice plants.

To develop an efficient gene tagging system in rice, a plasmid was constructed carrying a non-autonomous maize Ds element in the untranslated leader sequence of a hygromycin B resistance gene fused with the 35S promoter of cauliflower mosaic virus. This plasmid was cotransfected by electroporation into rice protoplasts together with a plasmid containing the maize Ac transposase gene transcribed from the 35S promoter. Five lines of evidence obtained from the analyses of hygromycin B-resistant calli, regenerated plants and their progeny showed that the introduced Ds was trans-activated by the Ac transposase gene in rice. (1) Cotransfection of the two plasmids is necessary for generation of hygromycin B resistant transformants. (2) Ds excision sites are detected by Southern blot hybridization. (3) Characteristic sequence alterations are found at Ds excision sites. (4) Newly integrated Ds is detected in the rice genome. (5) Generation of 8 bp target duplications is observed at the Ds integration sites on the rice chromosomes. Our results also show that Ds can be trans-activated by the transiently expressed Ac transposase at early stages of protoplast culture and integrated stably into the rice genome, while the cotransfected Ac transposase gene is not integrated. Segregation data from such a transgenic rice plant carrying no Ac transposase gene showed that four Ds copies were stably integrated into three different chromosomes, one of which also contained the functional hph gene restored by Ds excision. The results indicate that a dispersed distribution of Ds throughout genomes not bearing the active Ac transposase gene can be achieved by simultaneous transfection with Ds and the Ac transposase gene.