bor1-1, an Arabidopsis thaliana mutant that requires a high level of boron

bor1-1 (high boron requiring), an Arabidopsis thaliana mutant that requires a high level of B, was isolated. When the B concentration in the medium was reduced to 3 microM, the expansion of rosette leaves was severely affected in bor1-1 but not in wild-type plants. In a medium containing 30 microM B the mutant grew normally but showed female sterility, whereas the wild type was able to set seeds. These defects of the bor1-1 mutant were not detected with supplementation of 100 microM B. In vivo concentrations of B in bor1-1 mutants were lower than those of the wild type, especially in the inflorescence stems. Tracer experiments using 10B suggested that the mutant has defects in uptake and/or translocation of B. The mutation was mapped on the lower arm of chromosome 2.

Lipids in progression of renal disease

There is increasing evidence for the role of hyperlipidemia as a contributing factor to the progression of chronic renal disease. Experimental studies in animal models suggest that lipids might be important modulators in progressive renal disease. On one hand maneuvers designed to elevate cholesterol worsen renal disease while reduction of lipid-lowering agents have demonstrated beneficial effects. In humans, correcting abnormalities in lipid metabolism with antilipemic therapy may help slow the rate of functional decline in patients with progressive renal disease as well as reduce the frequency of acute rejection after renal transplantation. However, large controlled clinical trials examining the effect of lipid-lowering strategies on progression of renal disease have not been carried out. Further clinical trials delineating the precise role of antilipemic agents in treating patients with renal disease appears warranted.

Cord blood IgE against milk and egg antigens

The aim of the present study was to reevaluate the prenatal production of specific IgE for eggs and milk and, in those cases, to determine whether there is a relation to the amount of maternal egg and milk intake. Total and specific IgEs from 160 cord blood-samples were determined by immunoassays using a paramagnetic particle solid phase and an enzyme-mediated chemiluminescent reaction for signal detection. The levels of cord blood IgE for total, egg, and milk were 0.63 +/- (SD) 1.10 IU/ml, 0.020 +/- 0.055, and 0.036 +/- 0.053 IU/ml, respectively. IgE levels specific to egg and milk over 0.03 IU/ml were observed in 33 and 70 out of 160 cases, respectively. To address whether the maternal intake of eggs and milk affects the level of cord blood IgEs, all mothers except 9 were interviewed, and the amount of eggs and milk taken during pregnancy was recorded. No correlation was seen between egg and milk intakes and cord blood IgE levels. Our data demonstrate a high incidence of the prenatal production of specific IgE for eggs and milk which is independent of maternal egg and milk intakes.

Localization of hepatocyte growth factor and tubulointerstitial lesions in IgA nephropathy

To investigate the relationship between localization of hepatocyte growth factor (HGF) and tubulointerstitial lesions (TILs) in the cortical area of renal biopsy specimens, a clinicopathological study was performed in 35 patients with IgA nephropathy. HGF was detected by an enzyme-antibody method and TILs were assessed semiquantitatively by light microscopy. HGF was observed mainly on epithelial cells in the tubules, but not in the glomeruli. Fourteen patients had biopsies that were positive for HGF. There was a correlation between HGF positivity and histological damage, the TIL grade, and several clinical parameters determined at biopsy. Thus, HGF is related to TILs in IgA nephropathy, and may be a factor in the exacerbation of this disease.

Accumulation of Armadillo induced by Wingless, Dishevelled, and dominant-negative Zeste-White 3 leads to elevated DE-cadherin in Drosophila clone 8 wing disc cells

Drosophila genetic studies suggest that in the Wingless (Wg) signaling pathway, the segment polarity gene products, Dishevelled (Dsh), Zeste-white 3 (ZW-3), and Armadillo (Arm), work sequentially; wg and dsh negatively regulate zw-3, which in turn down-regulates arm. To biochemically analyze interactions between the Wg pathway and Drosophila E-cadherin (DE-cadherin) which bind to Arm, we overexpressed Dsh, ZW-3, and Arm, in the Drosophila wing disc cell line, clone 8, which responds to Wg signal. Dsh overexpression led to accumulation of Arm primarily in the cytosol and elevation of DE-cadherin at cell junctions. Overexpression of wild-type and dominant-negative forms of ZW-3 decreased and increased Arm levels, respectively, indicating that modulation in zw-3 activity negatively regulates Arm levels. Overexpression of an Arm mutant with an amino-terminal deletion elevated DE-cadherin levels, suggesting that Dsh-induced DE-cadherin elevation is caused by the Arm accumulation induced by Dsh. Moreover, the Dsh-, dominant-negative ZW-3-, and truncated Arm-induced accumulation of DE-cadherin protein was accompanied by a marked increase in the steady-state levels of DE-cadherin mRNA, suggesting that transcription of DE-cadherin is activated by Wg signaling. In addition, overexpression of DE-cadherin elevated Arm levels by stabilizing Arm at cell-cell junctions.

p16INK4 gene mutations are relatively frequent in ampullary carcinomas

A high incidence of gene mutations or deletions of p16INK4, a cell cycle regulator which inhibits the activity of cyclin-dependent kinase 4/cyclin D complex and blocks the G1-to-S transition, has been reported in pancreato-biliary tract cancers. In order to investigate p16INK4 gene alterations in sporadic ampullary carcinomas, 17 sporadic ampullary carcinomas were examined. After histological diagnosis, DNA samples extracted separately from both cancerous and normal paraffin-embedded tissues were investigated. Loss of heterozygosity (LOH) was investigated utilizing 3 microsatellite markers on 9p21-22, and a mutational analysis was performed by cloning and sequencing. LOH was observed in 3 cases (17.6%) and somatic mutations with retention of heterozygosity were found in 7 cases (41.2%). Of note was that two mutations resulted in truncated incomplete proteins and one was a point mutation at the consensus site in the conserved ankyrin repeats, which would be crucial for function. Although two-hit inactivation was not evident in any of the mutation cases and further investigation would be needed to elucidate the role of altered p16INK4, these results suggest that the p16INK4 gene mutations are relatively frequent and its inactivation might be important in ampullary carcinogenesis.

Analysis of low-molecular-mass proteins in cerebrospinal fluid by sodium dodecyl sulfate capillary gel electrophoresis

Proteins of low molecular (M(r)) in human cerebrospinal fluid (CSF) were analyzed by capillary electrophoresis in a sodium dodecyl sulfate-containing polymer solution. Under the conditions employed, peaks of beta 2-microglobulin (beta MG) (M(r): 11,700), gamma-trace protein (12,300), myelin basic protein (18,000), beta-trace protein (beta TP) (23,000 to 30,000) and alpha 1-acid glycoprotein (42,000) were detected on the electropherograms. The concentrations of beta MG and beta TP were determined based on the peak area relative to that of an internal standard, Orange G, which was added at a constant amount as the front marker. It was demonstrated that their levels in CSF change under various pathological conditions in the central nervous system.

High responsiveness to thyroid hormone of adult rat primary hepatocytes cultured on EHS-gel

The induction of malic enzyme gene expression by triiodothyronine and insulin was severely blunted in rat monolayer hepatocytes cultured on type I collagen compared with that in spherical hepatocytes cultured on a reconstituted basement membrane gel (EHS-gel). Although the mRNA level of thyroid hormone receptor beta (TR beta) gradually decreased in the monolayer hepatocytes during culture, the mRNA level in the hepatocytes on EHS-gel was maintained at around the in vivo level. Our results suggest that the maintenance of TR beta mRNA on EHS-gel is responsible for the high responsiveness to thyroid hormone in a hepatocyte culture.

Effects of cigarette smoking on the serum concentration of lung surfactant protein A (SP-A)

We have tested the hypothesis that serum surfactant protein A (SP-A) production may be affected by cigarette smoke exposure, and that alterations in serum levels may reflect smoking habits. A total of 52 subjects were divided into the following two groups: active smokers (Group A; n = 23); and nonsmokers (Group B; n = 29). The assessment of smoking habit was determined by self-report, carbon monoxide concentration in expired air, and cotinine concentration in urine. Serum SP-A was compared in both groups and was found to be higher in Group A (active smokers) (p < 0.002). We conclude that surfactant protein A levels are increased in the serum of smokers. However, it was found that this is not a sensitive discriminating factor to separate smokers from nonsmokers.

An autopsied case of acute myocarditis with myocardial calcification

A 47-year-old woman was admitted with fever, hypotension, an elevated serum creatinine kinase level, and electrocardiographic abnormalities, which led to the diagnosis of acute myocarditis. She was placed on percutaneous cardiopulmonary support because of hemodynamic collapse on the third hospital day. Serial echocardiography showed gradual recovery of profound hypokinesis and edematous thickening of the left ventricle, but she died of sepsis on the 17th day without overt renal insufficiency or electrolytic abnormalities. Autopsy revealed myocardial necrosis with lymphocytic infiltrates and extensive myocardial calcification. Calcification was dense in the area of severe myocardial necrosis, and the distribution of calcium deposits suggested that the calcification was a consequence of significant inflammation of the myocardium. Recovery of regional wall motion was prominent in the area of severe inflammatory change. Dissociation between the pathologic and echocardiographic findings suggested the possibility of functional reversibility of severely damaged myocardium and possible mechanisms of abnormal contractile function other than inflammatory change.

Frequent somatic mutations of the APC and p53 genes in sporadic ampullary carcinomas

Although a close relation of somatic mutations of the adenomatous polyposis coli gene with ampullary carcinomas in familial adenomatous polyposis patients has been reported, the possible association with sporadic ampullary neoplasms has not been fully examined. We have therefore investigated loss of heterozygosity at the adenomatous polyposis coli locus and the mutational status of a portion of the adenomatous polyposis coli gene, including the mutation cluster region, in 17 ampullary carcinomas of non-familial adenomatous polyposis patients. Alteration of the adenomatous polyposis coli gene was found in 8 of 17 (47.1%) cases, as missense or insertion mutations, with or without loss of heterozygosity. Additional investigation of p53 (exons 5-8) and K-ras (codons 12 and 13) gene mutations revealed a striking mutational pattern of the p53 gene. Nine of the 17 cases demonstrated a total of 12 mutations, 6 clustered at codon 189 and 3 at codon 166. Furthermore, 5 of the 12 mutations were nonsense mutations. Regarding the K-ras gene, 4 of the 17 (23.5%) cases had mutations in codon 12, 3 of the 4 cases being derived from the intraduodenal bile duct. The findings indicate that alterations of the adenomatous polyposis coli and the p53 genes are relatively frequent in sporadic ampullary carcinomas. In particular, the clustering at specific p53 codons might offer an etiological clue to clarify ampullary carcinogenesis. Mutations of the K-ras gene, on the other hand, might be characteristic of intraduodenal bile duct origin.

Cystic teratoma of the greater omentum: a case report and review of the literature

Cystic teratoma in the greater omentum remains one of gynecology's rarest entities. A 28-year-old woman presented with a goose-egg-sized mass in the right lower quadrant. At laparotomy, the mass proved to be a cystic teratoma of the greater omentum. To our knowledge, this report documents the first case where an omental pedicle was torsioned.

Inhibition of inducible nitric oxide synthase expression by endothelin in rat glial cells prepared from the neonatal rat brain

In primary cultured rat glial cells, a combination of inflammatory cytokines such as tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) stimulates production of nitrite via expression of the inducible form of nitric oxide synthase (iNOS). In these cells, simultaneous addition of endothelin (ET) decreased iNOS expression and nitrite accumulation induced by TNF-alpha/IL-1beta. The inhibitory effect of ET on TNF-alpha/IL-1beta-stimulated iNOS expression appears to be mediated by ET(B) receptors, because (1) both ET-1 and ET-3 inhibited the effects of TNF-alpha/IL-1beta on iNOS expression and nitrite accumulation, (2) a selective ET(B) receptor agonist, Suc-[Glu(9),Ala(11,15)]-ET-1 (8-21) (IRL1620), decreased the effects of TNF-alpha/IL-1beta, and (3) a selective ET(B) receptor antagonist, N-cis-2,6-dimethylpiperidinocarbonyl-L-gamma-methylleucyl-D- 1-methoxycarbonyltryptophanyl-D-norleucine, abolished the inhibitory effects of ETs and IRL1620. Incubation of glial cells with lipopolysaccharide (LPS) caused an increase in iNOS expression. Simultaneous addition of ET-3 decreased the effects of LPS (10 and 100 ng/ml) on iNOS expression. Furthermore, cyclic AMP-elevating agents (dibutyryl cyclic AMP and forskolin) inhibited TNF-alpha/IL-1beta-induced and LPS-induced iNOS expression and nitrite accumulation. These findings suggest that ETs can decrease TNF-alpha/IL-1beta-induced and LPS-induced iNOS expression via ET(B) receptors and that cyclic AMP may be involved in this process.

Prevalence of p53 mutations and protein expression in esophageal cancers in southern Thailand

To investigate p53 alterations in esophageal squamous-cell carcinomas of patients in the high-risk area of southern Thailand, 72 paraffin-embedded samples were analyzed immunohistochemically for p53 protein expression and 16 frozen samples for p53 mutational status. Forty-two of the 72 tumors (58.3%) showed p53 protein accumulation in the nuclei of tumor cells. Expression of p53 in tumors was not significantly correlated with gender, histological grading, depth of invasion, node involvement, smoking or alcohol consumption. Analysis of the p53 gene in a sub-set of 16 tumors showed mis-sense mutations in 7 out of 11 p53-positive and 1 out of 5 p53-negative tumors. The p53 mutational spectrum was 50% transitions (3 C-to-T and 1 G-to-A, all occurring at CpG dinucleotide sites) and 50% transversions (one each, C-to-G, G-to-T, T-to-G, and T-to-A). Our findings support the hypothesis that alterations of p53 are involved in the carcinogenesis of most squamous-cell carcinomas of the esophagus, irrespective of the population and the factors responsible for carcinogenesis. The mutation profile of the p53 gene might indicate etiologic contributions of different mutagen exposures in patients from high-risk areas of southern Thailand.

Regulation of expression of the human MTH1 gene encoding 8-oxo-dGTPase. Alternative splicing of transcription products

The enzyme 8-oxo-7,8-dihydrodeoxyguanosine triphosphatase (8-oxo-dGTPase) hydrolyzes 8-oxo-dGTP to 8-oxo-dGMP, thereby preventing misincorporation of 8-oxo-dGTP into DNA. We investigated expression of MTH1 gene encoding 8-oxo-dGTPase. Large amounts of MTH1 mRNA were present in thymus and testis, embryonic tissues, and certain cell lines. In peripheral blood lymphocytes, the level of MTH1 mRNA was significantly increased after concomitant treatment with phytohemagglutinin and interleukin-2. Analyses of the 5' regions of the MTH1 transcripts revealed that 7 types of MTH1 mRNAs, which may be produced by transcription initiation at different sites and/or alternative splicing. The MTH1 gene consists of 5 major exons, some of which are composed of differentially processed segments. All types of MTH1 mRNAs carry the entire coding region, and may be functional. Three ATG initiation codons in-frame were found in the 5' regions of some of the MTH1 mRNAs. There is a polymorphic alteration at the 5' splicing site (GT to GC) located in exon 2, an event which affects splicing patterns of the MTH1 transcript. Allele frequency of this polymorphism is about 20% among healthy volunteers.

Prevalence of p53 mutations and protein expression in esophageal cancers in southern Thailand

To investigate p53 alterations in esophageal squamous-cell carcinomas of patients in the high-risk area of southern Thailand, 72 paraffin-embedded samples were analyzed immunohistochemically for p53 protein expression and 16 frozen samples for p53 mutational status. Forty-two of the 72 tumors (58.3%) showed p53 protein accumulation in the nuclei of tumor cells. Expression of p53 in tumors was not significantly correlated with gender, histological grading, depth of invasion, node involvement, smoking or alcohol consumption. Analysis of the p53 gene in a sub-set of 16 tumors showed mis-sense mutations in 7 out of 11 p53-positive and 1 out of 5 p53-negative tumors. The p53 mutational spectrum was 50% transitions (3 C-to-T and 1 G-to-A, all occurring at CpG dinucleotide sites) and 50% transversions (one each, C-to-G, G-to-T, T-to-G, and T-to-A). Our findings support the hypothesis that alterations of p53 are involved in the carcinogenesis of most squamous-cell carcinomas of the esophagus, irrespective of the population and the factors responsible for carcinogenesis. The mutation profile of the p53 gene might indicate etiologic contributions of different mutagen exposures in patients from high-risk areas of southern Thailand.

[Non-Hodgkin's lymphoma associated with polymyositis]

A 67-year-old man was admitted to with severe nasal congestion. One year previously, he had been suffered from polymyositis (PM) and had been treated with prednisolone. Physical examination and computed tomography revealed a mass in the upper pharynx. Biopsy revealed non-Hodgkin's lymphoma (diffuse medium, B-cell type). Bone marrow aspiration also revealed the infiltration by lymphoma cells. The patient achieved a complete remission after combination chemotherapy (cyclophosphamide, adriamycin, vincristine, prednisolone). However, one month later, he suffered from central nervous system involvement of lymphoma cells, and he died of an aspiration pneumonia. Polymyositis/dermatomyositis associated with non-Hodgkin's lymphoma is extremely rare.

Role of intercellular adhesion molecule-1, lymphocyte function-associated antigen-1, and macrophages in ddY mouse nephropathy

ddY mouse nephropathy is an animal model of human IgA nephropathy that is characterized by spontaneous IgA deposition in the glomerular mesangium, mesangial cell proliferation, and matrix expansion. We investigated the involvement of intercellular adhesion molecule-1, lymphocyte function-associated antigen-1, and macrophages in the pathogenesis of ddY mouse nephropathy. Five mice each underwent urinalysis, light microscopic examination of the kidneys, immunofluorescent detection of immunoglobulins and complement, and immunohistochemical examination for intercellular adhesion molecule-1, lymphocyte function-associated antigen-1, and infiltrating macrophages at 5, 10, 20, 30, 40, 50, 60, and 70 weeks of age. Albuminuria was observed from the age of 20 weeks and all mice showed albuminuria by 70 weeks. Histological glomerular damage was significantly related to the appearance of albuminuria (p < 0.01). In the glomeruli, positivity for intercellular adhesion molecule-1 and lymphocyte function-associated antigen-1, as well as the number of infiltrating macrophages, were significantly increased in mice with nephropathy compared to pre-nephropathy mice (p < 0.01). These results suggest that intercellular adhesion molecule-1, lymphocyte function-associated antigen-1, and infiltrating macrophages are involved in the progression of histological damage in ddy mouse nephropathy.

Effect of lipoproteins on cultured human mesangial cells

It was recently reported that low-density lipoprotein (LDL) promotes mesangial cell proliferation, and oxidized LDL is cytotoxic for mesangial cells. However, there have been few studies about the effects of other lipoproteins on mesangial cells. Accordingly, we investigated the effect of various lipoproteins on cultured human mesangial cells using 3H-thymidine (3H-TdR) incorporation and cell counting assays. We also investigated the levels of several cytokines in mesangial cell culture supernatants after stimulation by the lipoproteins. Addition of very-low-density lipoprotein (VLDL) at concentrations up to 100 micrograms/mL, intermediate-density lipoprotein (IDL) at up to 50 micrograms/mL, and LDL at up to 50 micrograms/mL induced the proliferation of cultured human mesangial cells, whereas cell growth was inhibited at higher concentrations. Oxidized LDL caused a concentration-dependent decrease of 3H-TdR incorporation. High-density lipoprotein (HDL) had no proliferative effective effect at any concentration. Exposure to VLDL, IDL, LDL, or a high concentration of HDL enhanced the secretion of interleukin-6, platelet-derived growth factor, and transforming growth factor-beta by mesangial cells, whereas tumor necrosis factor-alpha secretion was stimulated by oxidized LDL. These finding indicate that triglyceride (TG)-rich lipoproteins (VLDL and IDL) promote mesangial cell proliferation as well as LDL, whereas oxidized LDL has the reverse effect. These effects of lipoproteins may be related to modulation of various cytokines. Accordingly, TG-rich lipoproteins, LDL, and oxidized LDL may be involved in mesangial cell proliferation and injury in patients with mesangial proliferative glomerulonephritis.

A case of nonpenetrating traumatic aortic regurgitation detected by transesophageal echocardiography

A 67-year-old man, who had fell 5 meters, landing on his back, one month before, was referred because of heart failure due to aortic regurgitation (AR). Transesophageal echocardiogram (TEE) confirmed injuries in the aortic valve and the Valsalva sinus of the aorta before the surgery: the intimal flap in the Valsalva sinus of right coronary cusp (RCC), the prolapse of the RCC, and the dissection by longitudinal length of 3 cm in the Valsalva sinus of noncoronary cusp (NCC), ending as a blind pouch. Postoperative TEE confirmed the dissection was not repaired in the Valsalva sinus of the NCC. In this instance, TEE was extremely useful, compared with transthoracic echocardiography, computed tomography and magnetic resonance imaging, to assess the mechanism of AR following a nonpenetrating trauma, and to know to what degree the aortic valve and the Valsalva sinus of the aorta were destroyed.

Role of transforming growth factor-beta 1 and -beta 2 in ddY mouse nephropathy

We investigated the glomerular distribution of transforming growth factor-beta (TGF-beta 1 and TGF-beta 2) protein and the expression of its mRNA, and related factors, in ddY mice, aged 5-60 weeks, before and after the onset of nephropathy, TGF-beta 1 protein expression was observed from the age of 20 weeks onwards, peaking at 50 weeks, and then declining. Expression of TGF-beta 2 protein gradually increased from 5 to 60 weeks. TGF-beta 1 and TGF-beta 2 mRNA were both detected from 5 to 60 weeks. The mesangial matrix expansion index (MMEI) was significantly higher in mice with nephropathy than in those without nephropathy, as was the expression of TGF-beta 1 and TGF-beta 2 proteins (P < 0.05). TGF-beta 2 was significantly positively correlated with the MMEI (P < 0.05). Infiltration of CD68-positive monocytes/macrophages gradually increased until 60 weeks, and was significantly correlated with the expression of TGF-beta 1 (P < 0.05) and TGF-beta 2 (P < 0.01). These findings indicate that TGF-beta 1 and TGF-beta 2 were overexpressed in ddY mice with overt nephropathy compared with pre-nephropathic mice. TGF-beta 2 may be an important mediator of mesangial matrix expansion in ddY mouse nephropathy.